Effect of B addition on the microstructures and mechanical properties of Nb–16Si–10Mo–15W alloy

林业工程学报，２０２３，８（４）：１０２－１０９ＪｏｕｒｎａｌｏｆＦｏｒｅｓｔｒｙＥｎｇｉｎｅｅｒｉｎｇＤＯＩ：１０．１３３６０／ｊ．ｉｓｓｎ．２０９６－１３５９．２０２２１１００７收稿日期：２０２２－１１－０７㊀㊀㊀㊀修回日期：２０２３－０３－２７基金项目：山东省重大科技创新工程（２０１９ＪＺＺＹ０１０３０５）㊂作者简介：林捷，男，研究方向为生物质复合材料㊂通信作者：孙丰文，男，研究员㊂Ｅ⁃ｍａｉｌ：ｓｕｎｆｗ＠ｎｊｆｕ．ｅｄｕ．ｃｎ相变微胶囊填充改性聚乙二醇／酚醛泡沫的制备林捷，张茜，魏信义，孙丰文∗（南京林业大学材料科学与工程学院，南京２１００３７）摘㊀要：相变微胶囊可以通过相变潜热的方式将能量储存在其内部，可作为储能材料用于保温㊁节能等领域㊂酚醛泡沫具有隔声㊁质轻㊁难燃㊁保温等优异性能，常用作城市建筑的墙体保温材料，但酚醛泡沫机械性能差㊁韧性低㊁粉化率高等缺点限制了其进一步发展㊂笔者以可发性酚醛树脂为原料，将其与聚乙二醇（ＰＥＧ⁃４００）和相变微胶囊（ＭＰＣＭ）进行共混发泡制备酚醛泡沫，研究不同质量分数的改性剂对酚醛泡沫物理力学性能㊁化学结构㊁微观结构㊁热学性能和隔声性能的影响㊂红外光谱测试结果表明，酚醛树脂中的羟基或羟甲基与聚乙二醇中的羟基发生了反应，将柔性长键引入到酚醛树脂的结构中㊂ＰＥＧ⁃４００降低了泡沫的粉化率，提高了泡沫的冲击韧性，ＭＰＣＭ的填充改性提高了泡沫的压缩强度㊂当添加质量分数为４％的ＰＥＧ⁃４００和１０％的ＭＰＣＭ时，泡沫的冲击韧性㊁表观密度和压缩强度分别提高了５６％，６３．９％和９５．９％，残炭率降低了１１．６％，隔声量降低了１．２％㊂当ＰＥＧ⁃４００和ＭＰＣＭ的添加量分别控制在４％和１０％时，泡沫的综合性能最佳㊂关键词：酚醛泡沫；相变材料；聚乙二醇；保温；增韧改性中图分类号：ＴＱ３２８㊀㊀㊀㊀㊀文献标志码：Ａ㊀㊀㊀㊀㊀文章编号：２０９６－１３５９（２０２３）０４－０１０２－０８Ｐｒｅｐａｒａｔｉｏｎａｎｄｃｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆｍｏｄｉｆｉｅｄｐｏｌｙｅｔｈｙｌｅｎｅｇｌｙｃｏｌ／ｐｈｅｎｏｌｉｃｆｏａｍｆｉｌｌｅｄｗｉｔｈｐｈａｓｅｃｈａｎｇｅｍｉｃｒｏｃａｐｓｕｌｅｓＬＩＮＪｉｅ，ＺＨＡＮＧＱｉａｎ，ＷＥＩＸｉｎｙｉ，ＳＵＮＦｅｎｇｗｅｎ∗（ＣｏｌｌｅｇｅｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，ＮａｎｊｉｎｇＦｏｒｅｓｔｒｙＵｎｉｖｅｒｓｉｔｙ，Ｎａｎｊｉｎｇ２１００３７，Ｃｈｉｎａ）Ａｂｓｔｒａｃｔ：Ｕｔｉｌｉｚａｔｉｏｎｏｆｇｒｅｅｎｅｎｅｒｇｙ⁃ｓａｖｉｎｇｂｕｉｌｄｉｎｇｍａｔｅｒｉａｌｓｉｎｔｈｅｂｕｉｌｄｉｎｇｉｎｄｕｓｔｒｙｉｓａｎｉｍｐｏｒｔａｎｔｗａｙｔｏｒｅｄｕｃｅｂｕｉｌｄｉｎｇｅｎｅｒｇｙｃｏｎｓｕｍｐｔｉｏｎ．Ｂｅｃａｕｓｅｏｆｔｈｅｌｏｗａｐｐａｒｅｎｔｄｅｎｓｉｔｙａｎｄｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙ，ｔｈｅｆｏａｍｍａｔｅｒｉａｌｉｓｏｆｔｅｎｕｓｅｄａｓｗａｌｌｉｎｓｕｌａｔｉｏｎｍａｔｅｒｉａｌｆｏｒｕｒｂａｎｂｕｉｌｄｉｎｇｓ．Ｔｒａｄｉｔｉｏｎａｌｉｎｓｕｌａｔｉｏｎｆｏａｍｍａｔｅｒｉａｌｓ，ｓｕｃｈａｓｐｏｌｙｖｉｎｙｌｃｈｌｏｒｉｄｅ，ｐｏｌｙｕｒｅｔｈａｎｅ，ａｎｄｐｏｌｙｓｔｙｒｅｎｅ，ｈａｖｅｐｏｏｒｆｌａｍｅ⁃ｒｅｔａｒｄａｎｔｐｅｒｆｏｒｍａｎｃｅａｎｄａｒｅｄｉｆｆｉｃｕｌｔｔｏｍｅｅｔｔｈｅｒｅｑｕｉｒｅｍｅｎｔｓｏｆｆｉｒｅｐｒｅｖｅｎｔｉｏｎｉｎｍｏｄｅｒｎｂｕｉｌｄｉｎｇｓ．Ｏｎｔｈｅｃｏｎｔｒａｒｙ，ｔｈｅｍｏｓｔｏｕｔｓｔａｎｄｉｎｇａｄｖａｎｔａｇｅｓｏｆｐｈｅｎｏｌｉｃｆｏａｍａｒｅｆｌａｍｅｒｅｓｉｓｔａｎｃｅ，ｌｏｗｓｍｏｋｅｐｒｏｄｕｃｔｉｏｎ，ａｎｄｃｒｅｅｐｒｅｓｉｓｔａｎｃｅａｔｈｉｇｈｔｅｍｐｅｒａｔｕｒｅｓ，ｓｏｔｈｅｐｈｅｎｏｌｉｃｆｏａｍｈａｓａｔｔｒａｃｔｅｄｔｈｅａｔｔｅｎｔｉｏｎｏｆｍａｎｙｒｅｓｅａｒｃｈｅｒｓａｎｄｅｎｇｉｎｅｅｒｓ．Ｂｕｔｔｈｅｐｈｅｎｏｌｉｃｆｏａｍｈａｓｔｈｅｄｒａｗｂａｃｋｓｏｆｐｏｏｒｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓ，ｌｏｗｔｏｕｇｈｎｅｓｓ，ａｎｄｈｉｇｈｐｕｌｖｅｒｉｚａｔｉｏｎｒａｔｅ，ｗｈｉｃｈｌｉｍｉｔｉｔｓｆｕｒｔｈｅｒａｐｐｌｉｃａｔｉｏｎｓ．Ｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓａｒｅｔｈｅｒｍａｌｌｙｆｕｎｃｔｉｏｎａｌｍａｔｅｒｉａｌｓ，ｉｎｗｈｉｃｈｅｎｅｒｇｙｉｓｓｔｏｒｅｄａｓｌａｔｅｎｔｈｅａｔ．Ｂｙａｄｄｉｎｇｐｈａｓｅｃｈａｎｇｅｓｕｂｓｔａｎｃｅｓｉｎｔｏｅｘｉｓｔｉｎｇｂｕｉｌｄｉｎｇｍａｔｅｒｉａｌｓ，ｅｎｅｒｇｙ⁃ｓａｖｉｎｇｂｕｉｌｄｉｎｇｉｎｓｕｌａｔｉｏｎｗａｌｌｓｗｉｔｈｇｏｏｄｈｅａｔｓｔｏｒａｇｅｐｅｒｆｏｒｍａｎｃｅｃａｎｂｅｐｒｅｐａｒｅｄ．Ｈｏｗｅｖｅｒ，ｍｏｓｔｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓｕｓｅｄｉｎｔｈｅｃｏｎｓｔｒｕｃｔｉｏｎｉｎｄｕｓｔｒｙａｒｅｓｏｌｉｄ⁃ｌｉｑｕｉｄｐｈａｓｅｃｈａｎｇｅ，ｗｈｉｃｈａｒｅｅａｓｙｔｏｌｅａｋａｆｔｅｒｍｅｌｔｉｎｇ．Ｔｈｅｒｅｆｏｒｅ，ｍｉｃｒｏｅｎｃａｐｓｕｌａｔｉｏｎｔｅｃｈｎｏｌｏｇｙｉｓａｇｏｏｄｓｏｌｕｔｉｏｎｔｏａｄｄｒｅｓｓｔｈｉｓｉｓｓｕｅ．Ｉｎｔｈｉｓｅｘｐｅｒｉｍｅｎｔ，ｔｈｅｐｈｅｎｏｌｉｃｆｏａｍｗｉｔｈｇｏｏｄｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓ，ｅｎｅｒｇｙｓｔｏｒａｇｅ，ａｎｄｓｏｕｎｄｉｎｓｕｌａｔｉｏｎｐｒｏｐｅｒｔｉｅｓｗａｓｐｒｅｐａｒｅｄｂｙｂｌｅｎｄｉｎｇｐｈｅｎｏｌｉｃｒｅｓｉｎｗｉｔｈｐｏｌｙｅｔｈｙｌｅｎｅｇｌｙｃｏｌ（ＰＥＧ⁃４００）ａｎｄｍｉｃｒｏｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓ（ＭＰＣＭ）．Ｉｎｔｈｉｓｐａｐｅｒ，ｔｈｅｅｆｆｅｃｔｓｏｆｄｉｆｆｅｒｅｎｔｍａｓｓｆｒａｃｔｉｏｎｓｏｆｍｏｄｉｆｉｅｒｓｏｎｔｈｅｐｈｙｓｉｃａｌａｎｄｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓ，ｃｈｅｍｉｃａｌｓｔｒｕｃ⁃ｔｕｒｅ，ｍｉｃｒｏｓｔｒｕｃｔｕｒｅ，ｔｈｅｒｍａｌｐｒｏｐｅｒｔｉｅｓ，ａｎｄｓｏｕｎｄｉｎｓｕｌａｔｉｏｎｐｒｏｐｅｒｔｉｅｓｏｆｔｈｅｐｈｅｎｏｌｉｃｆｏａｍｗｅｒｅｓｔｕｄｉｅｄ．ＴｈｅＦｏｕｒｉｅｒｔｒａｎｓｆｏｒｍｉｎｆｒａｒｅｄｓｐｅｃｔｒａｌａｎａｌｙｓｉｓｓｈｏｗｅｄｔｈａｔｔｈｅｈｙｄｒｏｘｙｌｏｒｈｙｄｒｏｘｙｍｅｔｈｙｌｇｒｏｕｐｓｏｆｔｈｅｐｈｅｎｏｌｉｃｒｅｓｉｎｒｅａｃｔｅｄｗｉｔｈｔｈｅｈｙｄｒｏｘｙｌｇｒｏｕｐｓｏｆｐｏｌｙｅｔｈｙｌｅｎｅｇｌｙｃｏｌ，ｉｎｔｒｏｄｕｃｉｎｇｆｌｅｘｉｂｌｅｌｏｎｇｂｏｎｄｓｉｎｔｏｔｈｅｓｔｒｕｃｔｕｒｅｏｆｔｈｅｐｈｅ⁃ｎｏｌｉｃｒｅｓｉｎ．Ｔｈｅｓｃａｎｎｉｎｇｅｌｅｃｔｒｏｎｍｉｃｒｏｓｃｏｐｅｉｍａｇｅｓｓｈｏｗｅｄｔｈａｔｔｈｅｐｈａｓｅｃｈａｎｇｅｍｉｃｒｏｃａｐｓｕｌｅｓｗｅｒｅｅｖｅｎｌｙｆｉｌｌｅｄｉｎｔｈｅｃｅｌｌｓｏｆｔｈｅｐｈｅｎｏｌｉｃｆｏａｍ．ＴｈｅａｄｄｉｔｉｏｎｏｆＰＥＧ⁃４００ｒｅｄｕｃｅｄｔｈｅｐｕｌｖｅｒｉｚａｔｉｏｎｒａｔｅｏｆｆｏａｍａｎｄｉｍｐｒｏｖｅｄｔｈｅｉｍ⁃ｐａｃｔｔｏｕｇｈｎｅｓｓｏｆｆｏａｍ，ａｎｄｔｈｅＭＰＣＭｍｏｄｉｆｉｃａｔｉｏｎｅｎｈａｎｃｅｄｔｈｅｃｏｍｐｒｅｓｓｉｏｎｓｔｒｅｎｇｔｈｏｆｔｈｅｆｏａｍ．ＷｈｅｎｔｈｅｍａｓｓｆｒｉｃｔｉｏｎｏｆＰＥＧ⁃４００ａｎｄＭＰＣＭｗｅｒｅ４％ａｎｄ１０％，ｒｅｓｐｅｃｔｉｖｅｌｙ，ｔｈｅｉｍｐａｃｔｔｏｕｇｈｎｅｓｓ，ａｐｐａｒｅｎｔｄｅｎｓｉｔｙ，ａｎｄｃｏｍ⁃㊀第４期林捷，等：相变微胶囊填充改性聚乙二醇／酚醛泡沫的制备ｐｒｅｓｓｉｖｅｓｔｒｅｎｇｔｈｏｆｔｈｅｆｏａｍｉｎｃｒｅａｓｅｄｂｙ５６％，６３．９％，ａｎｄ９５．９％，ｒｅｓｐｅｃｔｉｖｅｌｙ．Ｔｈｅｃａｒｂｏｎｒｅｓｉｄｕａｌｄｅｃｒｅａｓｅｄｂｙ１１．６％，ａｎｄｔｈｅｓｏｕｎｄｉｎｓｕｌａｔｉｏｎｃａｐａｃｉｔｙｄｅｃｒｅａｓｅｄｂｙ１．２％．ＷｈｅｎｔｈｅａｍｏｕｎｔｓｏｆＰＥＧ⁃４００ａｎｄＭＰＣＭｗｅｒｅ４％ａｎｄ１０％，ｒｅｓｐｅｃｔｉｖｅｌｙ，ｔｈｅｆｏａｍａｃｈｉｅｖｅｄｔｈｅｏｐｔｉｍａｌｏｖｅｒａｌｌｐｅｒｆｏｒｍａｎｃｅ．Ｋｅｙｗｏｒｄｓ：ｐｈｅｎｏｌｉｃｆｏａｍ；ｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓ；ｐｏｌｙｅｔｈｙｌｅｎｅｇｌｙｃｏｌ；ｉｎｓｕｌａｔｉｏｎ；ｔｏｕｇｈｅｎｉｎｇｍｏｄｉｆｉｃａｔｉｏｎ㊀㊀传统泡沫材料如聚氯乙烯㊁聚氨酯㊁聚苯乙烯等，具有优良的绝缘性能和机械性能，常用于建筑墙体的保温和货物的包装材料，但其阻燃性能较差，且燃烧时易产生刺激性的有毒气体［１］，限制了其在建筑领域的进一步应用㊂酚醛泡沫作为新一代的泡沫保温材料，其成本低㊁质轻㊁低毒㊁阻燃㊁发烟量低㊁耐高温蠕变㊁耐腐蚀㊁化学性质稳定，受到众多研究者的广泛关注［２－３］㊂但是，酚醛树脂分子内部存在大量仅靠亚甲基键相连的类如苯环的刚性结构，缺乏柔性长链基团，由于亚甲基键键短，酚醛树脂分子空间位阻大，链节旋转自由度小［４］，酚醛泡沫机械性能差㊁韧性低㊁粉化率高㊂针对酚醛泡沫的这些缺陷，众多学者对其进行增韧改性研究㊂目前，酚醛泡沫的改性方式可以分为两类：物理增韧改性和化学增韧改性［５］㊂物理增韧也称为外增韧，就是将可发性酚醛树脂与柔性的改性剂直接进行混合，两者之间不发生任何化学反应㊂目前常用的物理增韧剂主要有橡胶［６］㊁热塑性树脂［７］和纤维［８－９］㊂马玉峰等［１０］先使用ＫＨ⁃５５０和碱液处理木纤维，再将其作为增韧改性剂制备酚醛泡沫，结果表明，木纤维经过ＫＨ⁃５５０和碱液处理后，其与酚醛树脂的界面相容性明显改善，木纤维的引入提高了泡沫的机械性能㊂化学增韧法是指在树脂合成反应中引入增韧剂，例如在羟甲基和酚羟基上接入烃基长链或者其他柔性基团㊂柔性链段的引入可以改变酚醛泡沫原有的机械性能㊂当外力作用在增韧改性后的酚醛泡沫上，材料可以通过自身形变来吸收一部分能量，避免材料出现应力集中，从而改善材料的韧性㊁降低粉化率［１１］㊂宋飞［１２］合成了１种含磷桐油基硅氧烷，并将其作为增韧剂制备酚醛泡沫，结果表明，柔性长链的引入提高了泡沫的压缩㊁弯曲强度，隔热性能，阻燃性以及抑烟性能㊂此外，将相变材料引入现有的建筑材料制成具有良好蓄热性能的节能建材也是当前的研究热点之一㊂相变材料是１种热功能性材料，可以相变潜热的方式将能量储存在材料内部㊂通过应用场景的转换和时间的推移，可以实现能量在不同时空位置上的传递与转换㊂与其他绝缘材料不同，相变材料在达到其熔化温度时会吸收大量热量，并随着固化释放其储存的潜热㊂相变储能具有相变潜热大㊁价格低廉㊁适用范围广㊁环境友好等优点［１３］㊂但是，目前建筑行业所使用的相变材料大多数发生的是固⁃液相变，在熔融后相变材料容易泄露㊂对相变材料进行微胶囊化包覆，可有效解决其易泄露问题，并且微胶囊化可预防相变材料与外界其他物质发生反应，保护内部的相变材料并减少有害物质污染环境［１４］㊂相变微胶囊可以直接添加在石膏板㊁混凝土中，也可以将其与聚氨酯㊁环氧树脂混合发泡制备保温泡沫材料［１５－１６］㊂因此，笔者通过聚乙二醇和相变微胶囊对酚醛泡沫进行复合改性，在改善泡沫韧性的同时赋予其一定的蓄热性能，以开发１种具有良好阻燃㊁隔声㊁蓄热性能的新型建筑材料㊂１㊀材料与方法１．１㊀材料和试剂正戊烷㊁吐温⁃８０㊁磷酸㊁聚乙二醇４００（ｐｏｌｙｅｔｈｙ⁃ｌｅｎｅｇｌｙｃｏｌ⁃４００，ＰＥＧ⁃４００），分析纯，均购于上海麦克林生化有限公司；对甲苯磺酸㊁盐酸，化学纯，均购于国药集团化学试剂有限公司；酚醛树脂，固体含量为８３．７６％，黏度为９２２０ｍＰａ㊃ｓ，ｐＨ为６．７，含水率４．６４％，由南京太尔化工提供；相变微胶囊（相变材料为正十八烷，囊壁材料为聚甲基丙烯酸甲酯），胶囊粒径５ １０μｍ，购自安徽美科迪智能微胶囊科技有限公司㊂１．２㊀样品制备将４０ｇ可发性酚醛树脂㊁２ｇ表面活性剂（吐温⁃８０）㊁６ｇ发泡剂（正戊烷）㊁６．４ｇ固化剂（固化剂：自制，盐酸㊁对甲苯磺酸㊁磷酸㊁水质量比为１ʒ４ʒ３ʒ２）加入５００ｍＬ烧杯中，使用高速机械搅拌机以４００ｒ／ｍｉｎ的速率搅拌６０ｓ㊂将混合均匀后的原料倒入发泡模具，放入７０ħ的烘箱中，固化３０ｍｉｎ㊂待样品冷却完毕后进行脱模取样，制备得到酚醛泡沫（ｐｈｅｎｏｌｉｃｒｅｓｉｎ，ＰＦ）㊂取４０ｇ树脂和一定质量分数（酚醛树脂质量的２％，４％和６％）的ＰＥＧ⁃４００加入烧杯中，使用高速机械搅拌机以８００ｒ／ｍｉｎ的转速搅拌６０ｓ㊂然后，依次加入发泡剂，搅拌均匀后倒入发泡模具，放３０１林业工程学报第８卷入烘箱进行发泡，制备得到聚乙二醇改性酚醛泡沫（２％ＰＥＧ⁃４００／ＰＦ㊁４％ＰＥＧ⁃４００／ＰＦ和６％ＰＥＧ⁃４００／ＰＦ）㊂先将一定质量分数（酚醛树脂质量的５％，１０％和１５％）的相变微胶囊粉末（ｍｉｃｒｏｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓ，ＭＰＣＭ）加入４０ｇ酚醛树脂中，在４０ ５０ħ下超声分散２０ｍｉｎ㊂按上述配比，依次加入聚乙二醇和发泡剂，制备相变微胶囊填充改性聚乙二醇／酚醛泡沫（５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ㊁１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ和１５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ）㊂将制备得到的泡沫切除外皮，置于通风橱中熟化４８ｈ，使泡沫中残余发泡剂挥发㊂１．３㊀材料测试与表征１．３．１㊀力学性能的测定表观密度按照国标ＧＢ／Ｔ６３４３ ２００９‘泡沫塑料及橡胶表观密度测定“进行测量；压缩强度按照ＧＢ／Ｔ８８１３ ２００８‘硬质泡沫塑料压缩性能的测定“，采用型号为ＣＭＴ４３０３的微机控制电子万能材料试验机进行测定；冲击强度按ＧＢ／Ｔ１０４３．１２００８‘塑料简支梁冲击性能的测定“进行测试㊂每组制备９个样品进行性能测试，最终结果取９次测量后的平均值㊂１．３．２㊀粉化率的测定粉化率按照国标ＧＢ／Ｔ１２８１２ ２００６‘硬质泡沫塑料易碎性的测定“进行测试㊂将试样制备成３０ｍｍˑ３０ｍｍˑ３０ｍｍ的立方体㊂先将样品置于粒径４８μｍ（３００目）的砂纸上，再将质量为２００ｇ的砝码置于样品正上方，以恒定的力量在３００目砂纸上摩擦２５０ｍｍ距离，反复摩擦３０次㊂每组制备９个样品进行性能测试，最终结果取９次测量后的平均值㊂称量试验前后试样质量，利用摩擦后试样的质量损失率来表征粉化率㊂粉化率计算如下：ｍｔ＝ｍ１－ｍ２ｍ１ˑ１００％（１）式中：ｍｔ为粉化率；ｍ１为泡沫初始质量，ｇ；ｍ２为磨损后泡沫质量，ｇ㊂１．３．３㊀傅里叶红外光谱测试将泡沫研磨成粉末，采用ＫＢｒ压片法，使用ＶＥＲＴＥＸ８０Ｖ型红外光谱仪进行扫描分析，波数范围为４００ ４０００ｃｍ－１㊂１．３．４㊀微观形貌观察采用Ｑｕａｎｔａ２００型环境扫描电子显微镜观察泡沫断面的微观结构，并根据扫描电镜图利用软件Ｎａｎｏｍｅａｓｕｒｅ１．２计算泡孔尺寸，绘制分布图㊂１．３．５㊀热重测试采用ＴＧ２０９Ｆ３型热重分析仪对试样进行热性能分析，测试条件为：氮气氛围，升温速率为１０ħ／ｍｉｎ，升温范围为３０ ８００ħ，氮气流速为１０ｍＬ／ｍｉｎ，参比物为Ａｌ２Ｏ３坩埚㊂１．３．６㊀差示扫描量热仪测试采用ＤＳＣ２００Ｆ３型差示扫描量热仪对样品的焓值进行测试㊂氮气氛围，升温速率１０ħ／ｍｉｎ，０ ８０ħ循环３次㊂１．３．７㊀导热系数的测定采用ＨＦＭ４３６型导热系数测定仪（德国耐驰公司）测定样品在２５ħ时的导热系数，每组测试３次，取平均值㊂１．３．８㊀隔声性能测试按照ＧＢ／Ｔ１８６９６．２ ２００２‘声学阻抗管中吸声系数和声阻抗的测量：第２部分：传递函数法“对酚醛泡沫的隔声性能进行测定，每组测试３次，取平均值㊂２㊀结果与分析２．１㊀聚乙二醇改性酚醛泡沫的粉化率和冲击韧性ＰＥＧ⁃４００是一种高分子聚合物，具有良好的水溶性，并且与高分子有机物有很好的相容性㊂聚乙二醇改性酚醛泡沫的粉化率和冲击韧性见图１㊂由图１可知，随着ＰＥＧ⁃４００的加入，酚醛泡沫的粉化率不断降低，冲击韧性呈现先增加后降低的趋势㊂图１结果表明，ＰＥＧ⁃４００提高了酚醛泡沫的冲击韧性，降低了酚醛泡沫的粉化率，可能是ＰＥＧ⁃４００与酚醛树脂分子发生化学反应，在酚醛树脂结构中接入了柔性长链，最终达到了增韧的效果㊂图１㊀聚乙二醇改性酚醛泡沫的粉化率和冲击韧性Ｆｉｇ．１㊀ＦｒａｇｉｌｉｔｙａｎｄｉｍｐａｃｔｔｏｕｇｈｎｅｓｓｏｆＰＥＧ⁃４００ｍｏｄｉｆｉｅｄｐｈｅｎｏｌｉｃｆｏａｍｓ２．２㊀聚乙二醇改性酚醛泡沫的表观密度和压缩强度㊀㊀聚乙二醇改性酚醛泡沫的表观密度和压缩强４０１㊀第４期林捷，等：相变微胶囊填充改性聚乙二醇／酚醛泡沫的制备度见图２㊂由图２可知，泡沫的压缩强度随着聚乙二醇添加量的增加逐渐降低，而酚醛泡沫的表观密度随着聚乙二醇添加量的增加呈现先增加后降低的趋势㊂当体系中ＰＥＧ⁃４００的添加量较低时，ＰＥＧ⁃４００会填充部分泡沫空隙，导致密度变大；但添加量过多后会导致体系黏度降低，减小泡孔的图２㊀聚乙二醇改性酚醛泡沫的表观密度和压缩强度Ｆｉｇ．２㊀ＡｐｐａｒｅｎｔｄｅｎｓｉｔｉｅｓａｎｄｃｏｍｐｒｅｓｓｉｏｎｓｔｒｅｎｇｔｈｓｏｆＰＥＧ⁃４００ｍｏｄｉｆｉｅｄｐｈｅｎｏｌｉｃｆｏａｍｓ生长阻力，可能在泡沫形成过程中出现大孔，导致密度降低㊂结合ＰＥＧ⁃４００添加量对酚醛泡沫粉化率和冲击韧性的影响，当ＰＥＧ⁃４００添加量为４％时，酚醛泡沫的综合性能最优，满足后续实验要求㊂２．３㊀相变微胶囊填充改性酚醛泡沫的物理力学性能㊀㊀实验选用的ＭＰＣＭ具有良好的机械性能和蓄热性能㊂相变微胶囊填充改性酚醛泡沫的物理力学性能测定结果见图３㊂由图３可知，ＭＰＣＭ的加入对酚醛泡沫的粉化率影响不大，但会提高泡沫的冲击韧性，当ＭＰＣＭ添加量为１０％时冲击韧性较ＰＦ提高了５６．０％㊂随着ＭＰＣＭ添加量的增加，改性酚醛泡沫的表观密度和压缩强度显著提高，当ＭＰＣＭ添加量为１０％时，表现密度和压缩强度分别提高了６３．９％和９５．９％㊂ＭＰＣＭ的加入，会导致体系黏度增大，影响泡孔生长，降低发泡倍率㊂同时由于ＭＰＣＭ的粒径较小，可以均匀地分散在泡孔中，起到了类似于填料的作用，提高了酚醛泡沫的压缩强度㊂图３㊀相变微胶囊填充改性酚醛泡沫的物理力学性能Ｆｉｇ．３㊀Ｐｈｙｓｉｃａｌａｎｄｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｍｏｄｉｆｉｅｄｐｈｅｎｏｌｉｃｆｏａｍｓｆｉｌｌｅｄｗｉｔｈｐｈａｓｅｃｈａｎｇｅｍｉｃｒｏｃａｐｓｕｌｅｓ２．４㊀酚醛泡沫的傅里叶红外光谱酚醛泡沫改性前后的红外光谱分析结果见图４㊂未改性酚醛泡沫红外光谱图显示，３４３４ｃｍ－１位置为羟基的伸缩振动峰，２９２４ｃｍ－１处为羟甲基键的伸缩振动峰，１６１７ｃｍ－１处为苯环中碳碳双键的伸缩振动峰㊂从图４可以看出：在１１７５ １２７５ｃｍ－１处出现Ｃ Ｏ Ｃ的特征吸收峰，说明聚乙二醇的羟基与酚醛树脂中的羟基发生了部分反应［１７］，成功在酚醛树脂的分子结构上引入了柔性长链，从而起到了增韧的效果㊂在ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ的红外图谱中，２９１５和２８４５ｃｍ－１处的高强度峰是正十八烷分子中甲基的对称伸缩振动峰和亚甲基的不对称伸缩振动峰，１４６８和１３７３ｃｍ－１处的吸收峰是亚甲基和甲基中Ｃ Ｈ的弯曲振动峰；２９５２和１７３４ｃｍ－１处的吸收峰分别为聚甲基丙烯酸甲酯的Ｃ Ｈ与Ｃ Ｏ的伸缩振动峰，而１１９９和１１６１ｃｍ－１处的双吸收峰属于Ｃ Ｏ的伸缩振动峰［１８］㊂上述特征峰表明，相变微胶囊与酚醛树脂充分混合，形成了ＭＰＣＭ／ＰＦ复合材料，且ＭＰＣＭ的引入没有改变酚醛树脂基体的化学结构㊂图４㊀酚醛泡沫的傅里叶红外光谱Ｆｉｇ．４㊀ＦＴ⁃ＩＲｃｕｒｖｅｓｏｆｐｈｅｎｏｌｉｃｆｏａｍｓ５０１林业工程学报第８卷２．５㊀酚醛泡沫的微观形貌分析酚醛泡沫的断面微观形貌见图５㊂图５ａ为ＰＦ的微观结构图，未改性泡沫的泡孔结构不均匀，开孔率较高，泡孔大多呈现椭圆形㊂相比之下，ＰＥＧ⁃４００改性后泡沫的泡孔结构更加均匀㊂但随着ＰＥＧ⁃４００含量的增加，泡沫的开孔率逐渐增大㊂泡孔孔径分布见图６，图６ａ显示纯ＰＦ的平均孔径为１４１．４０μｍ，孔径大小分布范围为９０ ２００μｍ㊂ＰＥＧ⁃４００的添加对酚醛泡沫的孔径影响不大，２％ＰＥＧ⁃４００／ＰＦ㊁４％ＰＥＧ⁃４００／ＰＦ和６％ＰＥＧ⁃４００／ＰＦ的平均孔径分别为１３６．２３，１６０．５９和１４２．５６μｍ㊂综合来看，４％ＰＥＧ⁃４００改性后的酚醛泡沫具有最佳的泡孔结构㊂ａ）ＰＦ；ｂ）２％ＰＥＧ⁃４００／ＰＦ；ｃ）４％ＰＥＧ⁃４００／ＰＦ；ｄ）６％ＰＥＧ⁃４００／ＰＦ；ｅ）５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ；ｆ，ｈ）１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ；ｇ，ｉ）１５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ㊂图５㊀酚醛泡沫的ＳＥＭ图Ｆｉｇ．５㊀ＳＥＭｉｍａｇｅｓｏｆｐｈｅｎｏｌｉｃｆｏａｍｓａ）ＰＦ；ｂ）２％ＰＥＧ⁃４００／ＰＦ；ｃ）４％ＰＥＧ⁃４００／ＰＦ；ｄ）６％ＰＥＧ⁃４００／ｆ）１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ；ｇ）１５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ㊂图６㊀酚醛泡沫的泡孔孔径分布Ｆｉｇ．６㊀Ｃｅｌｌｓｉｚｅｄｉｓｔｒｉｂｕｔｉｏｎｓｏｆｐｈｅｎｏｌｉｃｆｏａｍｓ㊀㊀图５ｅ ｇ为ＭＰＣＭ填充改性后的酚醛泡沫放大８００倍的微观结构图㊂与纯酚醛泡沫相比，ＭＰＣＭ改性后泡沫的平均孔径减小㊂由图６ｅ ｇ可知，ＭＰＣＭ的添加会减小酚醛泡沫的孔径㊂５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ㊁１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ和１５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ的平均孔径分别为８５．６８，９９．１８和１１０．２０μｍ，与ＰＦ相比分别降低了３９．４％，２９．９％和２２．１％㊂可能有以下两种原因：①分散均６０１㊀第４期林捷，等：相变微胶囊填充改性聚乙二醇／酚醛泡沫的制备匀的ＭＰＣＭ作为成核剂，可以降低临界成核自由能，从而增加了形成的气泡核的数量；②混合ＭＰＣＭ后泡沫的黏度增大，限制了细胞的生长㊂图５ｈ㊁ｉ为１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ和１５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ放大２０００倍的图片，可以很明显地看见ＭＰＣＭ较为均匀地分散在泡沫中㊂２．６㊀酚醛泡沫的热性能分析２．６．１㊀热稳定性改性泡沫的热重（ｔｈｅｒｍｏｇｒａｖｉｍｅｔｒｙ，ＴＧ）和微分热重（ｄｅｒｉｖａｔｉｖｅｔｈｅｒｍｏｇｒａｖｉｍｅｔｒｙ，ＤＴＧ）曲线见图７㊂从图７ａ可看出，８００ħ条件下酚醛泡沫的残炭率为５７．８％㊂低于１００ħ时，泡沫的质量损失是由于其内部的残余水分和发泡剂的挥发㊂在１００２００ħ，泡沫的降解主要是材料的进一步固化脱水和酚醛树脂的降解；３００ ５００ħ时，泡沫开始分解，高分子链降解为单个苯环；５００ ８００ħ时，苯环结构炭化程度进一步增大㊂图７㊀改性泡沫的ＴＧ和ＤＴＧ曲线Ｆｉｇ．７㊀ＴＧａｎｄＤＴＧｃｕｒｖｅｓｏｆｔｈｅｐｈｅｎｏｌｉｃｆｏａｍｓ㊀㊀ＰＥＧ⁃４００的分解温度与酚醛泡沫材料不同，所以ＰＥＧ⁃４００／ＰＦ的ＴＧ曲线较ＰＦ相比也有所差异㊂从图７ｂ可以看出，ＰＥＧ⁃４００改性酚醛泡沫材料在２００ ３００ħ时的分解速率高于酚醛泡沫，这主要是因为ＰＥＧ⁃４００在此段温度内发生了分解㊂随着ＰＥＧ⁃４００添加量的增加，泡沫的残炭率不断降低㊂８００ħ时，２％，４％和６％ＰＥＧ⁃４００改性酚醛泡沫的残炭率分别为５６．４％，５５．３％和５３．７％㊂相较于ＰＦ和ＰＥＧ⁃４００／ＰＦ，ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ在２００ ３００ħ和４００ ５００ħ两个阶段的分解速率远快于前两者㊂其中，２００ ３００ħ的质量损失主要归因于囊芯相变材料正十八烷的分解；４００ ５００ħ的失重是囊壁材料ＰＭＭＡ分解引起的㊂５％，１０％和１５％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ在８００ħ的残炭率分别为５４．４％，５１．１％和４７．９％㊂由于ＰＥＧ⁃４００和ＭＰＣＭ的分解温度都低于酚醛泡沫，改性后试样的残炭率出现了一定程度的降低㊂当ＰＥＧ⁃４００的质量分数为４％㊁ＭＰＣＭ的质量分数不超过１０％时，泡沫的残炭率均仍在５０％以上，泡沫依然具有较好的热稳定性㊂２．６．２㊀热熔融结晶行为相变微胶囊酚醛泡沫的差示扫描量热（ｄｉｆｆｅｒ⁃ｅｎｔｉａｌｓｃａｎｎｉｎｇｃａｌｏｒｉｍｅｔｒｙ，ＤＳＣ）曲线见图８㊂由图８可见，未添加相变微胶囊的酚醛泡沫在升温过程中无吸热峰㊂在添加相变微胶囊后，泡沫的ＤＳＣ升温曲线出现了吸热峰，这是由于胶囊内部的相变材料发生固⁃液相变㊂添加相变微胶囊的酚醛泡沫在降温阶段出现了两个结晶峰，这是由于相变微胶囊内部的正十八烷在结晶时会发生异相成核和均相成核㊂吸热峰的出现表明了ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ具有了一定的蓄热保温㊁调节温度的功能㊂随着ＭＰＣＭ含量的增加，泡沫的熔融焓也逐渐增大㊂ＭＰＣＭ的添加量为５％，１０％和１５％时，样品的熔融焓分别为２．８８，５．７４和８．５０Ｊ／ｇ，结晶焓为２．３６，４．９７图８㊀酚醛泡沫ＤＳＣ分析图Ｆｉｇ．８ＤＳＣａｎａｌｙｓｉｓｏｆｐｈｅｎｏｌｉｃｆｏａｍｓ２．６．３㊀导热性能酚醛泡沫的导热系数见图９㊂由图９可知，样品的导热系数随着ＰＥＧ⁃４００添加量的增加呈先上７０１林业工程学报第８卷升后下降的趋势㊂当ＰＥＧ⁃４００添加量较小时，泡沫的表观密度增加，导热系数随之变大；当ＰＥＧ⁃４００添加量进一步增加时，改性泡沫体的表观密度逐渐降低，导热系数随之变小㊂此时，泡沫的导热系数主要受到泡孔结构的影响㊂随着ＭＰＣＭ含量的增加，泡沫的导热系数也是呈先上升后下降的趋势㊂此时，样品的导热系数主要由表观密度和相变材料的吸热决定㊂当泡沫的表观密度增大，其导热系数随之增大；而当相变微胶囊添加量提高，泡沫的焓值增加，会导致泡沫的导热系数下降㊂当ＭＰＣＭ添加量为５％时，样品的导热系数最大，此时泡沫的表观密度对导热系数起到主导作用㊂随着ＭＰＣＭ含量的进一步增加，相变材料的吸热会导致泡沫导热系数逐渐降低㊂图９㊀酚醛泡沫的导热系数Ｆｉｇ．９㊀Ｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｉｅｓｏｆｐｈｅｎｏｌｉｃｆｏａｍｓ２．７㊀酚醛泡沫的隔声性能综合来看，当ＭＰＣＭ添加量为１０％时，泡沫的综合性能最佳，所以此处选用ＰＦ㊁４％ＰＥＧ⁃４００和１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ３种泡沫进行隔声性能测试㊂酚醛泡沫隔声测试曲线见图１０㊂由图１０可见，随着频率的增加，酚醛泡沫的隔声量在７５０Ｈｚ处出现１个隔声低谷，此时入射波和泡沫中的弯曲波波长相同，泡沫的振动与入射声波之间形成共振，绝大部分的声波从泡沫中穿过㊂与之相反，４％ＰＥＧ⁃４００改性泡沫在频率７００Ｈｚ处出现了１个波峰，这可能是ＰＥＧ⁃４００的引入改变了泡沫原有的结构，阻碍了泡沫的弯曲振动，降低了泡沫的振动幅度，进而削弱了共振现象，提高了隔声效果㊂在中高频段，泡沫的隔声量随着频率的增加不断提高㊂该频带下泡沫一般难以被激发振动，所以隔声性能逐渐增强㊂ＰＦ㊁４％ＰＥＧ⁃４００／ＰＦ和１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ平均隔声量分别为１２．８１，１４．９４和１２．６６ｄＢ㊂ＰＥＧ⁃４００的加入增强了泡沫的隔声性能，４％ＰＥＧ⁃４００／ＰＦ的平均隔声量相比ＰＦ提高了２．１３ｄＢ㊂ＭＰＣＭ的引入会使泡沫密度增大㊁发泡倍率变小，从而影响泡沫的隔声效果㊂但１０％ＭＰＣＭ／ＰＥＧ⁃４００／ＰＦ平均隔声量较ＰＦ变化不大，这可能是由于ＭＰＣＭ带来的负面效果与ＰＥＧ⁃４００增强的效果相抵消㊂图１０㊀酚醛泡沫隔声测试曲线Ｆｉｇ．１０㊀Ｓｏｕｎｄｉｎｓｕｌａｔｉｏｎｃｕｒｖｅｓｏｆｐｈｅｎｏｌｉｃｆｏａｍｓ３㊀结㊀论１）通过添加ＰＥＧ⁃４００和相变微胶囊与酚醛树脂进行共混发泡，制备出性能优异的改性泡沫㊂ＦＴ⁃ＩＲ的结果显示，ＰＥＧ⁃４００和酚醛树脂分子中的羟基或羟甲基发生了反应㊂ＳＥＭ的结果显示，相变微胶囊均匀地填充在泡沫的泡孔中㊂２）经ＰＥＧ⁃４００改性后，泡沫的压缩强度和粉化率逐渐降低，冲击强度明显增大㊂ＰＥＧ⁃４００的加入在一定程度降低了泡沫的保温性和热稳定性，但提高了隔声性能㊂３）ＭＰＣＭ的加入一定程度上降低了泡沫的热稳定性㊁保温性能和隔声性能，但也让泡沫具有一定的蓄热保温㊁调节温度的功能㊂当添加质量分数为４％的ＰＥＧ⁃４００和１０％的ＭＰＣＭ时，泡沫的综合性能最优㊂参考文献（Ｒｅｆｅｒｅｎｃｅｓ）：［１］ＳＯＮＧＦ，ＬＩＺ，ＪＩＡＰＹ，ｅｔａｌ．Ｐｈｏｓｐｈｏｒｕｓ⁃ｃｏｎｔａｉｎｉｎｇｔｕｎｇｏｉｌ⁃ｂａｓｅｄｓｉｌｏｘａｎｅｔｏｕｇｈｅｎｅｄｐｈｅｎｏｌｉｃｆｏａｍｗｉｔｈｇｏｏｄｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓ，ｆｉｒｅｐｅｒｆｏｒｍａｎｃｅａｎｄｌｏｗｔｈｅｒｍａｌｃｏｎｄｕｃｔｉｖｉｔｙ［Ｊ］．Ｍａｔｅｒｉａｌｓ＆Ｄｅｓｉｇｎ，２０２０，１９２：１０８６６８．ＤＯＩ：１０．１０１６／ｊ．ｍａｔｄｅｓ．２０２０．１０８６６８．［２］ＭＯＵＧＥＬＣ，ＧＡＲＮＩＥＲＴ，ＣＡＳＳＡＧＮＡＵＰ，ｅｔａｌ．Ｐｈｅｎｏｌｉｃｆｏａｍｓ：ａｒｅｖｉｅｗｏｆｍｅｃｈａｎｉｃａｌｐｒｏｐｅｒｔｉｅｓ，ｆｉｒｅｒｅｓｉｓｔａｎｃｅａｎｄｎｅｗｔｒｅｎｄｓｉｎｐｈｅｎｏｌｓｕｂｓｔｉｔｕｔｉｏｎ［Ｊ］．Ｐｏｌｙｍｅｒ，２０１９，１６４：８６－１１７．ＤＯＩ：１０．１０１６／ｊ．ｐｏｌｙｍｅｒ．２０１８．１２．０５０．［３］崔亚平，朱时雪，方娟．天然纤维黄麻增强保温酚醛泡沫性能研究［Ｊ］．塑料科技，２０２１，４９（３）：４３－４７．ＤＯＩ：１０．１５９２５／ｊ．ｃｎｋｉ．ｉｓｓｎ１００５－３３６０．２０２１．０３．０１０．ＣＵＩＹＰ，ＺＨＵＳＸ，ＦＡＮＧＪ．Ｓｔｕｄｙｏｎｐｒｏｐｅｒｔｉｅｓｏｆｎａｔｕｒａｌｆｉｂｅｒｊｕｔｅｒｅｉｎｆｏｒｃｅｄｉｎｓｕｌａｔｉｏｎｐｈｅｎｏｌｉｃｆｏａｍ［Ｊ］．ＰｌａｓｔｉｃｓＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙ，２０２１，４９（３）：４３－４７．８０１㊀第４期林捷，等：相变微胶囊填充改性聚乙二醇／酚醛泡沫的制备［４］赵继永，王志鹏，程世婧，等．高性能聚合物泡沫材料的制备性能与应用研究进展［Ｊ］．高分子材料科学与工程，２０２０，３６（６）：１３６－１４４．ＤＯＩ：１０．１６８６５／ｊ．ｃｎｋｉ．１０００－７５５５．２０２０．０１１５．ＺＨＡＯＪＹ，ＷＡＮＧＺＰ，ＣＨＥＮＧＳＪ，ｅｔａｌ．Ｐｒｅｐａｒａｔｉｏｎ，ｐｒｏ⁃ｐｅｒｔｉｅｓａｎｄａｐｐｌｉｃａｔｉｏｎｓｏｆｈｉｇｈ⁃ｐｅｒｆｏｒｍａｎｃｅｐｏｌｙｍｅｒｉｃｆｏａｍｍａｔｅ⁃ｒｉａｌｓ［Ｊ］．ＰｏｌｙｍｅｒＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅ＆Ｅｎｇｉｎｅｅｒｉｎｇ，２０２０，３６（６）：１３６－１４４．［５］许国娟，贾晨辉，刘晶，等．酚醛树脂增韧改性研究进展及应用现状概述［Ｊ］．复合材料科学与工程，２０２１（９）：１１８－１２８．ＤＯＩ：１０．１９９３６／ｊ．ｃｎｋｉ．２０９６－８０００．２０２１０９２８．０１８．ＸＵＧＪ，ＪＩＡＣＨ，ＬＩＵＪ，ｅｔａｌ．Ｔｏｕｇｈｉｎｇｍｏｄｉｆｉｃａｔｉｏｎｄｅｖｅｌｏｐ⁃ｍｅｎｔａｎｄｔｈｅａｐｐｌｉｃａｔｉｏｎｓｔａｔｕｓｏｆｐｈｅｎｏｌｉｃｒｅｓｉｎ［Ｊ］．ＣｏｍｐｏｓｉｔｅｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，２０２１（９）：１１８－１２８．［６］刘书萌，吴东森，刘鹏波．硅橡胶增韧改性酚醛泡沫的性能研究［Ｊ］．塑料科技，２０１４，４２（１１）：５７－６０．ＤＯＩ：１０．１５９２５／ｊ．ｃｎｋｉ．ｉｓｓｎ１００５－３３６０．２０１４．１１．０２９．ＬＩＵＳＭ，ＷＵＤＳ，ＬＩＵＰＢ．Ｓｔｕｄｙｏｎｐｒｏｐｅｒｔｉｅｓｏｆｓｉｌｉｃｏｎｅｒｕｂ⁃ｂｅｒｔｏｕｇｈｅｎｅｄｐｈｅｎｏｌｉｃｆｏａｍ［Ｊ］．ＰｌａｓｔｉｃｓＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙ，２０１４，４２（１１）：５７－６０．［７］陈永鑫．改性酚醛泡沫原位填充芳纶蜂窝复合材料的制备工艺研究［Ｄ］．南京：南京航空航天大学，２０１４．ＣＨＥＮＹＸ．Ｓｔｕｄｙｏｎｔｈｅｐｒｅｐａｒａｔｉｏｎｔｅｃｈｎｏｌｏｇｙｏｆａｒａｍｉｄｃｅｌｌｕｌａｒｃｏｒｅｆｉｌｌｅｄｗｉｔｈｐｈｅｎｏｌｉｃｆｏａｍｓｉｎｓｉｔｕ［Ｄ］．Ｎａｎｊｉｎｇ：ＮａｎｊｉｎｇＵｎｉｖｅｒｓｉｔｙｏｆＡｅｒｏｎａｕｔｉｃｓａｎｄＡｓｔｒｏｎａｕｔｉｃｓ，２０１４．［８］ＹＡＮＧＹＦ，ＨＥＪＭ．Ｍｅｃｈａｎｉｃａｌｃｈａｒａｃｔｅｒｉｚａｔｉｏｎｏｆｐｈｅｎｏｌｉｃｆｏａｍｓｍｏｄｉｆｉｅｄｂｙｓｈｏｒｔｇｌａｓｓｆｉｂｅｒｓａｎｄｐｏｌｙｕｒｅｔｈａｎｅｐｒｅｐｏｌｙｍｅｒ［Ｊ］．ＰｏｌｙｍｅｒＣｏｍｐｏｓｉｔｅｓ，２０１５，３６（９）：１５８４－１５８９．ＤＯＩ：１０．１００２／ｐｃ．２３０６６．［９］谢梅竹，马磊，赵绘婷，等．植物纤维增强阻燃酚醛泡沫的制备及性能研究［Ｊ］．塑料科技，２０２２，５０（１０）：４９－５３．ＤＯＩ：１０．１５９２５／ｊ．ｃｎｋｉ．ｉｓｓｎ１００５－３３６０．２０２２．１０．０１０．ＸＩＥＭＺ，ＭＡＬ，ＺＨＡＯＨＴ，ｅｔａｌ．Ｐｒｅｐａｒａｔｉｏｎａｎｄｐｒｏｐｅｒｔｉｅｓｏｆｐｌａｎｔｆｉｂｅｒｒｅｉｎｆｏｒｃｅｄｆｌａｍｅｒｅｔａｒｄａｎｔｐｈｅｎｏｌｉｃｆｏａｍ［Ｊ］．ＰｌａｓｔｉｃｓＳｃｉｅｎｃｅａｎｄＴｅｃｈｎｏｌｏｇｙ，２０２２，５０（１０）：４９－５３．［１０］马玉峰，耿祥，王春鹏，等．桉木纤维预处理对酚醛泡沫复合材料性能的影响［Ｊ］．林业工程学报，２０１８，３（１）：９７－１０２．ＤＯＩ：１０．１３３６０／ｊ．ｉｓｓｎ．２０９６－１３５９．２０１８．０１．０１６．ＭＡＹＦ，ＧＥＮＧＸ，ＷＡＮＧＣＰ，ｅｔａｌ．Ｅｆｆｅｃｔｏｆｐｒｅｔｒｅａｔｍｅｎｔｏｆｅｕｃａｌｙｐｔｕｓｆｉｂｅｒｏｎｐｒｏｐｅｒｔｉｅｓｏｆｃｏｍｐｏｓｉｔｅｐｈｅｎｏｌｉｃｆｏａｍｓ［Ｊ］．ＪｏｕｒｎａｌｏｆＦｏｒｅｓｔｒｙＥｎｇｉｎｅｅｒｉｎｇ，２０１８，３（１）：９７－１０２．［１１］刘海翔，杜官本，邓书端．酚醛泡沫材料改性的研究进展［Ｊ］．化工新型材料，２０２２，５０（１１）：４２－４８．ＤＯＩ：１０．１９８１７／ｊ．ｃｎｋｉ．ｉｓｓｎ１００６－３５３６．２０２２．１１．００９．ＬＩＵＨＸ，ＤＵＧＢ，ＤＥＮＧＳＤ．Ｒｅｓｅａｒｃｈｐｒｏｇｒｅｓｓｏｎｍｏｄｉｆｉｃａ⁃ｔｉｏｎｏｆｐｈｅｎｏｌｉｃｆｏａｍｍａｔｅｒｉａｌ［Ｊ］．ＮｅｗＣｈｅｍｉｃａｌＭａｔｅｒｉａｌｓ，２０２２，５０（１１）：４２－４８．［１２］宋飞．基于桐油的酚醛泡沫材料增韧和阻燃改性及其结构和性能研究［Ｄ］．北京：中国林业科学研究院，２０２０．ＳＯＮＧＦ．Ｓｔｕｄｙｏｎｔｏｕｇｈｅｎｉｎｇａｎｄｆｌａｍｅ⁃ｒｅｔａｒｄａｎｔｍｏｄｉｆｉｃａｔｉｏｎｏｆｐｈｅｎｏｌｉｃｆｏａｍｍａｔｅｒｉａｌｂａｓｅｄｏｎｔｕｎｇｏｉｌａｎｄｉｔｓｓｔｒｕｃｔｕｒｅａｎｄｐｒｏｐｅｒｔｉｅｓ［Ｄ］．Ｂｅｉｊｉｎｇ：ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆＦｏｒｅｓｔｒｙ，２０２０．［１３］方桂花，张文涛，于孟欢．定形相变储能材料的研究进展［Ｊ］．化工新型材料，２０２２，５０（８）：３９－４２．ＤＯＩ：１０．１９８１７／ｊ．ｃｎｋｉ．ｉｓｓｎ１００６－３５３６．２０２２．０８．００８．ＦＡＮＧＧＨ，ＺＨＡＮＧＷＴ，ＹＵＭＨ．Ｒｅｓｅａｒｃｈａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆｓｈａｐｅ⁃ｓｔａｂｉｌｉｚｅｄＰＣＭｆｏｒｅｎｅｒｇｙｓｔｏｒａｇｅ［Ｊ］．ＮｅｗＣｈｅｍｉｃａｌＭａｔｅｒｉａｌｓ，２０２２，５０（８）：３９－４２．［１４］ＡＲＳＨＡＤＡ，ＪＡＢＢＡＬＭ，ＹＡＮＹＹ，ｅｔａｌ．Ｔｈｅｍｉｃｒｏ⁃／ｎａｎｏ⁃ＰＣＭｓｆｏｒｔｈｅｒｍａｌｅｎｅｒｇｙｓｔｏｒａｇｅｓｙｓｔｅｍｓ：ａｓｔａｔｅｏｆａｒｔｒｅｖｉｅｗ［Ｊ］．ＩｎｔｅｒｎａｔｉｏｎａｌＪｏｕｒｎａｌｏｆＥｎｅｒｇｙＲｅｓｅａｒｃｈ，２０１９，４３：５５７２－５６２０．ＤＯＩ：１０．１００２／ｅｒ．４５５０．［１５］ＹＡＮＧＣＧ，ＦＩＳＣＨＥＲＬ，ＭＡＲＡＮＤＡＳ，ｅｔａｌ．Ｒｉｇｉｄｐｏｌｙｕｒｅ⁃ｔｈａｎｅｆｏａｍｓｉｎｃｏｒｐｏｒａｔｅｄｗｉｔｈｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓ：ａｓｔａｔｅ⁃ｏｆ⁃ｔｈｅ⁃ａｒｔｒｅｖｉｅｗａｎｄｆｕｔｕｒｅｒｅｓｅａｒｃｈｐａｔｈｗａｙｓ［Ｊ］．ＥｎｅｒｇｙａｎｄＢｕｉｌｄｉｎｇｓ，２０１５，８７：２５－３６．ＤＯＩ：１０．１０１６／ｊ．ｅｎｂｕｉｌｄ．２０１４．１０．０７５．［１６］ＡＭＡＲＡＬＣ，ＰＩＮＴＯＳＣ，ＳＩＬＶＡＴ，ｅｔａｌ．Ｄｅｖｅｌｏｐｍｅｎｔｏｆｐｏｌｙ⁃ｕｒｅｔｈａｎｅｆｏａｍｉｎｃｏｒｐｏｒａｔｉｎｇｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｆｏｒｔｈｅｒｍａｌｅｎｅｒｇｙｓｔｏｒａｇｅ［Ｊ］．ＪｏｕｒｎａｌｏｆＥｎｅｒｇｙＳｔｏｒａｇｅ，２０２０，２８：１０１１７７．ＤＯＩ：１０．１０１６／ｊ．ｅｓｔ．２０１９．１０１１７７．［１７］孙恒，杨鹏，刘蓓蓓．聚乙二醇对酚醛树脂泡沫增韧效果的研究［Ｊ］．山东化工，２０１８，４７（１７）：２２－２６．ＤＯＩ：１０．１９３１９／ｊ．ｃｎｋｉ．ｉｓｓｎ．１００８－０２１ｘ．２０１８．１７．００９．ＳＵＮＨ，ＹＡＮＧＰ，ＬＩＵＢＢ．Ｓｔｕｄｙｏｎｔｏｕｇｈｅｎｉｎｇｅｆｆｅｃｔｏｆｐｈｅ⁃ｎｏｌｉｃｒｅｓｉｎｆｏａｍｓａｄｄｅｄｐｏｌｙｅｔｈｙｌｅｎｅｇｌｙｃｏｌ［Ｊ］．ＳｈａｎｄｏｎｇＣｈｅｍｉ⁃ｃａｌＩｎｄｕｓｔｒｙ，２０１８，４７（１７）：２２－２６．［１８］申晋琛，林明桂，马中义，等．十八烷＠聚甲基丙烯酸甲酯微胶囊相变材料的制备及表征［Ｊ］．燃料化学学报，２０２２，５０（１１）：１５１１－１５１６．ＤＯＩ：１０．１９９０６／ｊ．ｃｎｋｉ．ｊｆｃｔ．２０２２０５６．ＳＨＥＮＪＣ，ＬＩＮＭＧ，ＭＡＺＹ，ｅｔａｌ．Ｐｒｅｐａｒａｔｉｏｎａｎｄｃｈａｒａｃｔｅ⁃ｒｉｚａｔｉｏｎｏｆＯｃｔ＠ＰＭＭＡｍｉｃｒｏｃａｐｓｕｌｅｓｐｈａｓｅｃｈａｎｇｅｍａｔｅｒｉａｌｓ［Ｊ］．ＪｏｕｒｎａｌｏｆＦｕｅｌＣｈｅｍｉｓｔｒｙａｎｄＴｅｃｈｎｏｌｏｇｙ，２０２２，５０（１１）：１５１１－１５１６．（责任编辑㊀丁春香）９０１。

The effect of femtosecond laser micromachining on the surface characteristics and subsurface microstructure of amorphousFeCuNbSiB alloyWei Jia *,Zhinong Peng,Zhijun Wang,Xiaochang Ni,Ching-yue WangUltrafast Laser Laboratory,School of Precision Instruments and Optoelectrons Engineering,Tianjin University,Tianjin 300072,PR China Received 10September 2005;received in revised form 11January 2006;accepted 1February 2006Available online 6March 2006AbstractDetailed studies on the effects of femtosecond laser ablation on surface characteristics and subsurface microstructure of amorphous FeCuNbSiB alloy are reported.Three types of ripple structures were observed on the material surface in the gentle ablated (damaged)zone.As observed with X-ray diffraction (XRD),amorphous form is kept in the damaged zone,and there is few crystallization form in ablation zone.#2006Elsevier B.V .All rights reserved.PACS:52.38.Mf;75.50.KjKeywords:Laser ablation;Femtosecond laser;Amorphous alloy;Micromachining1.IntroductionFe-based amorphous alloys have been applied to magnetic components for their high magnetic flux density.The amorphous FeCuNbSiB alloy,known as FINEMET alloy,has been extensively studied [1,2],due to its excellent soft magnetic properties.In the case of a strong temperature rise,crystallization would take place and some of their properties would be lost.In recent years,the use of femtosecond laser pulses for precision micromachining has drawn tremendous interests.Many studies have demonstrated the advantages of femtose-cond laser pulses over longer laser pulses,including the negligible heat affected zone,precise ablation threshold,high repeatability and efficiency,highly precise control of ablation geometry and the ability to ablate structures below diffraction limited zones [3–6].Femtosecond lasers provide the unique property to machine nearly any kind of materials with their ultra-precise and mechanical/chemical damage-free material processing capabilities.The processing result is nearly free ofmolten layers and burr.Therefore,the femtosecond laser is the best candidate for amorphous alloy micromachining.The purpose of this study was to investigate multiple-pulse accumulation behavior on amorphous FeCuNbSiB alloy.The damage morphologies as well as the evolution of the damage morphology with the pulse fluence and shot number are concerned.Correlation was made between the observed damage morphologies and the relevant material removal mechanisms.2.ExperimentalThe ablation of all samples was performed using a commercially available femtosecond micromachining work-station (Clark-MXR,UMW-2110i).The pulse width,central wavelength and the repetition rate were 150fs,775nm and 1kHz,respectively.The maximum pulse energy was of 1mJ.The laser pulses were focused by a NA =0.14,5Âobjective lens.As-quenched specimens of amorphous FeCuNbSiB alloy ribbon were prepared by the melt spinning method.The alloy is nominal composed of atomic 73.5%Fe,1%Cu,3%Nb,13.5%Si and 9%B.The dimension of the samples was 40mm squared and the thickness was 0.02mm./locate/apsuscApplied Surface Science 253(2006)1299–1303*Corresponding author.Fax:+862227404204.E-mail address:************.cn (W.Jia).0169-4332/$–see front matter #2006Elsevier B.V .All rights reserved.doi:10.1016/j.apsusc.2006.02.003A Philips XL30ESEM with energy dispersive X-ray micro analyzer (EDX)was used for SEM/EDX analysis.XRD analyses were conducted on a Rigaku D/max 2500V PC diffractometer with Cu K a radiation.3.Results and discussions 3.1.Ablated surface characteristicsFig.1is the evolution of the ablated crater in amorphous FeCuNbSiB alloy ribbon at a fluence of 3.18J/cm 2,after increasing numbers of incident laser shots.The ripple patterns are clearly observed.The ripple formation is a well-known phenomena which has been discussed extensively [7–9].The incident laser light was partially scattered by surface defects into a tangential wave,which travels across the material surface.The ripples then were originated from the interference between the incident laser light and the scattered tangential wave.Three types of ripples can be observed in Fig.1b,in which the short periodicity ripple (L $l )parallel to the polarization of the incident laser (short parallel ripple)can be seen and is marked by ‘‘ripple I’’.Also shown in this figure (close to the center of laser ablated area)is the long periodicity ripples (L $2.7m m)perpendicular to the polarization of the incident laser (long perpendicular ripple)marked by ‘‘ripple II’’.The short periodicity ripple (L $l )is parallel to the polarization of the incident laser (short parallel ripple)and is marked by ‘‘ripple III’’,which is superimposed on the long perpendicular ripples.The periodicity of the short parallel ripple is almost constant everywhere in Fig.1,but,the periodicity of the long parallel ripples broadens from L $1.0to $2.7m m with the laser intensity increment.It is like that of diamond film [10],except that the periodicity of the short parallel ripple is longer (L $l for FeCuNbSiB and L $l /4for diamond film).At this point,it is like that of Cu [11]and stainless steel (L $l )[9].As the shot number increases,the extent of ripple (modification)area expands.This indicates the accumulation behavior of the pared with Fig.1b,the ripple II in Fig.1a is weaker.This implies that the threshold of laser intensity for short parallel ripples is lower than that of the long perpendicular ripples.While in Fig.1c and d,the ripple II changes gradually from continued to broken,and in the meantime,the ripple III gradually disappears.The SEM images show little evidence of material melting in the vicinity of the ripple patterns,thus suggesting that equilibrium vaporization is the mechanism responsible for material removal during ripple formation [9].W.Jia et al./Applied Surface Science 253(2006)1299–13031300Fig.1.SEM images of crates produced in amorphous FeCuNbSiB alloy ribbon at 3.18J/cm 2:(a)10shots,(b)20shots,(c)50shots and (d)100shots.Fig.2is the evolution of the ablated crater in amorphous FeCuNbSiB alloy ribbon atfluence of 6.36J/cm2,after increasing numbers of incident laser shots.It is apparent from Fig.2b that thefluence of6.36J/cm2was high enough to cause flat surface melting in the case of the20shot craters.It appears that,unlike the case of the craters produced at lowerfluences at the same shot numbers,some liquidflow has occurred,which has obscured the ripple patterns and resulted in aflat re-solidified area at the centers of the craters.It is possible that after further irradiation,i.e.100shots,this liquid layer has progressed further into the material and has undergone phase explosion due to superheating,resulting in the kind of morphology(strong ablation)visible in Fig.2(d).The observed morphologies seem consistent with a rapid expulsion of liquid and vapor droplets which then cooled quickly and re-solidified.To further examine the influence of thermal diffusion,the femtosecond laser machined surface was examined by EDX. The EDX data of a typicalflat re-solidified area(ablation zone, Fig.3-1)and a typical ripple patterns(damage zone,Fig.3-2)is listed in Table1,together with the EDX data of the as-quenched sample for comparison.Because the boron is a light element,it could not be identified below10%content.So,the nominal composite of neglecting boron is also listed in Table1.It is apparent that the EDX data of the ablated zone and the as-quenched sample exhibits a similar data to that from the atomic composition of the amorphous FeCuNbSiB alloy ribbon.The data confirm that the removal magnitude of different elements in the ripple pattern zone is variant.It seems consistent with that the equilibrium vaporization is the mechanism responsible for material removal during ripple formation,and the removal magnitude of different elements is different in the equilibrium vaporization;And that the removal magnitude of different elements in theflat re-solidified zone is uniform,the phase explosion is the most probable and efficient mechanism for material removal in theflat re-solidified zone. Most of the heated material reaches vaporization temperature, and it make that all of elements rapid vaporize synchronously. Therefore,the removal magnitude of different element in the flat re-solidified zone is close and the effect of femtosecond laser micromachining on the elemental composition is very little.3.2.Effect of ablation on subsurface microstructureThe XRD spectrum of the damage zone and the ablated zone are shown in Fig.4,together with the spectra obtained from theW.Jia et al./Applied Surface Science253(2006)1299–13031301Fig.2.SEM images of crates produced in amorphous FeCuNbSiB alloy ribbon at6.36J/cm2:(a)10shots,(b)20shots,(c)50shots and(d)100shots.as-quenched sample for comparison.From the curve of the as-quenched sample in Fig.4,we see no sharp peak in its diffraction pattern,and there is only a broad diffuse peak at around 40–508.This indicates that the specimen has an amorphous structure.There is only a broad diffuse peak at around 40–508in the XRD spectrum obtained from the damage zone yet.No crystallization could be detected.It is a similar pattern to that from the as-quenched sample.This confirms that the crystal structure presented in the damage zone is amorphous phase.However,the diffusion peak in the curve obtained from the ablated zone came to a point (2u =44.228)appreciably.This point is close to 43.6298,which is corresponding to the a -Fe (110),that is the first crystalline phase to appear in the amorphous Fe 73.5Cu 1Nb 3-Si 13.5B 9alloy irradiated with long pulse laser [2].Therefore,it showed that there was few crystallization in the ablated zone with femtosecond laser pulses.The above results are apparently opposite to that of the EDX analysis.Those results from the EDX analysis with electron beam does not penetrate deeply and only surface information is shown;However,X-ray could go deeper into the sample and show subsurface information.The equilibrium vaporization appears at lower energy fluence,and it only affect the element distribution of surface layer,therefore it makes few effect on XRD result;the liquid flow occur at a larger energy fluence,andthe thermal diffusion propagates to a deeper subsurface layer.But the effect of femtosecond laser micromachining on the elemental composition is very little.This is because the interaction time is very short,and few melted layers were abruptly cooled down and transformed into amorphous back [12].The XRD spectrum indicates that the ablated zone of femtosecond laser pulses was kept in amorphous alloy,with minimum crystallization.4.ConclusionsThe effects of femtosecond laser ablation on surface characteristics and subsurface microstructure of an amorphous FeCuNbSiB alloy were experimentally studied.Ripples were observed on the material surface during the weakly ablated zone and around the strong ablated zone.As observed with X-ray diffraction (XRD)measurements,the amorphous form is kept with no change in the damaged zone,and there is few crystallization form in ablation zone.This result indicates that the femtosecond laser ablation is not limited to direct a solid–vapor transition,but also involves significant substrate heating and structural transformations.AcknowledgmentsThe authors gratefully acknowledge the financial support by Tianjin Committee of Science and Technology (043103911),and State Key Laboratory of Ultraprecision Processing Technique (51464010205JW14).W.Jia et al./Applied Surface Science 253(2006)1299–13031302Fig.3.Typical flat re-solidified zone and ripple pattern zone for EDX analysis.Table 1Fe 73.5Cu 1Nb 3Si 13.5B 9(atom percentage)SampleFe Cu Nb Si B Neglecting boron 80.8 1.1 3.314.8–As-quenched 79.06 1.19 3.4616.29–Ablation zone 81.320.95 3.4114.32–Damage zone91.601.031.615.76–Fig.4.The XRD of amorphous alloy ribbon before and after laser micro-machining.References[1]Y.Yoshizawa,S.Oguma,K.Yamaguchi,J.Appl.Phys.64(1988)6044.[2]M.Sorescu,E.T.Knobbe,D.Barb,J.Phys.Chem.Solids56(1995)79.[3]X.Liu,D.Du,G.Mourou,IEEE J.Quantum Electron.33(1997)1706.[4]B.N.Chichkov,C.Momma,S.Nolte,F.V.Alvensleben,A.Tu¨nnermannn,Appl.Phys.A63(1996)109.[5]Y.Hirayama,M.Obara,Appl.Surf.Sci.197–198(2002)741.[6]J.M.Shieh,Z.H.Chen,B.T.Dai,et al.Appl.Phys.Lett.85(2004)1232.[7]A.Borowiec,H.K.Haugen,Appl.Phys.Lett.82(2003)4462.[8]J.Sipe,J.Young,J.Preston,H.Driel,Phys.Rev.B27(1983)1141.[9]P.T.Mannion,J.Magee,E.Coyne,G.M.O’Connor,T.J.Glynn,Appl.Surf.Sci.233(2004)275.[10]Q.H.Wu,Y.R.Ma,R.C.Fang,et al.Appl.Phys.Lett.82(2003)1703.[11]S.E.Kirkwood,A.C.Van Popta,Y.Y.Tsui,R.Fedosejevs,Appl.Phys.A81(2004)729.[12]J.Jia,M.Li,C.V.Thompson,Appl.Phys.Lett.84(2004)3205.W.Jia et al./Applied Surface Science253(2006)1299–13031303。

0前言随着新能源汽车的发展，为了减轻车身自重增加电池续航能力，车身及其配件也逐渐走向轻量化方向[1]。

因此，具有比重低及高安全性的铝合金成为车身零部件首选材料，其涵盖的产品有门槛梁、防撞梁、吸能盒、电池箱体等[2-3]。

同时许多大型车企针对不同的车用铝合金也做出了标准要求。

德国大众在2016年更新的TL116标准协议中，要求所提供的铝合金产品应按对应类别达到相应力学性能，此外还需满足一定的长期热稳定性、短期热稳定性以及焊合要求。

为了对门槛梁产品（以TL116-N28为技术标准）进行前期开发，本研究以某门槛梁产品为案例生产挤压型材，通过正交试验法研究挤压温度、时效温度及时效时间对产品基础性能影响，并选出最佳挤压工艺进行生产验证，同时按照TL116-N28标准进行检测，为后续合金的应用以及相关产品的开发提供依据。

1材料与试验方案1.1样本制备按表1所示成分（成分要求均在TL116标准内）熔铸铝棒材料，以某型号门槛梁挤压型材为案例生产制备样本，产品截面如图1所示。

工艺为：使用经560℃保温8h 均匀化消除成分偏析及残余应力的试验合金铸棒，在4000t 的挤压机上生产，主缸速度控制在2.4～2.8m/min ，淬火方式为喷水。

大众TL116-N28标准的铝合金门槛梁生产工艺研究蓝嘉昕，邓涛涛，王素杰，蔡知之（佛山市三水凤铝铝业有限公司，广东省铝型材加工与装备企业重点实验室，佛山528133）摘要：使用试验合金作为材料，结合正交试验得出门槛梁产品的最佳生产工艺参数，并以大众TL116-N28技术要求作为产品的检验标准。

结果表明，在挤压温度为490℃、时效制度为175℃/12h 工艺下，生产的门槛梁挤压型材的综合性能最佳，其抗拉强度为311.8MPa ，屈服强度为299.0MPa ，断后延伸率为11.7%。

按大众TL116-N28标准进行检验，材料在205℃/1h 处理后其力学性能未见明显降低，在150℃/1000h 处理后屈服强度为281MPa （＞265MPa ）。

・20・临床眼科杂志2021年第29卷1期Joumal P CAnical OphthnAoAgy,2221,V o U29,No.1•临床研究-内界膜剥除预防孔源性视网膜脱离术后黄斑前膜形成的有效性和安全性分析付燕杨娜耿任飞李丽英张月玲顾朝辉【摘要】目的探讨预防性内界膜（IOM）剥除预防孔源性视网膜脱离（RRD）复位术后黄斑前膜（ERM）发生的有效性和对视力及视网膜结构的影响。

方法收纳2212年）月至2213年6月就诊于我院的RRD行玻璃体切割术后成功复位者，共114例（12只眼）纳入研究,根据玻璃体切割术中是否行IOM剥除分为IOM剥除组和无OM 剥除组。

所有受检者行23G玻璃体切割联合硅油眼内填充，视网膜成功复位者均于玻切术后3~5个月行硅油取出术。

术前及玻璃体切割术后1、3、6、12个月进行复查，至末次随访。

比较两组间视力和黄斑区微结构的改变包括中央视网膜厚度（CRT）、椭圆体带（EZ）和外界膜（ELM）连续性，是否存在黄斑水肿及视网膜下液（SRF）。

结果术后114只眼中ERM形成者19只眼，占12.7%o94.7%ERM形成者发生于术后6个月内。

术后3、6、12个月，组间ERM形成率差异有统计学意义（均P<0.05）。

两组患者术后1m2个月BCVA较术前均明显提高，差异有统计学意义（均P<0.05）。

术后不同时间点BCVA的组间比较差异无统计学意义。

ERM形成和未发生ERM 者AgMAR BCVA分别为（0.52±0.312,31±0.68）,差异有统计学意义（t=-2.341,P<0.05）。

两组间CRT、EZ、ELM连续性、黄斑水肿和SRF发生率比较无统计学意义。

结论预防性OM剥除可有效预防RRD术后ERM 发生，且对视力和视网膜微结构改变无影响。

【关键词】孔源性视网膜脱离;黄斑前膜;内界膜剥除;视力;玻璃体切割术[临床眼科杂志,2021,29:20] Efficacy and safety of internal limiting membrane peeling in preventing epiretinal membrane formation after rhegmatogenous retinal detachment Fu Yag,Yang Na,Geng Renfei,Li Li-ying,Zhang Yueling,Gu Zhaohui.De­partment of Ophthalmology,Baohing First(Central Hospital,Baohing071000,China[Abstract t Objective To i/vestWate the effectiveness of pmphyActic internai limiting membrane(ILM)peeling in the prevenUon of eyimacular membrane(ERM)after rgeymaWgenous reti/ai deWchment(RRD)reductWc,as welt as its effect on visual acuity and reti/ai s WucWae.Methods A wtai of 114 consecutive patients(114eyes i with rgeymaWge-nous reti/ai detachment successfully treated with vitrectomy in our hospital from2016to2013were reWospectiveA ana­lyzed i The patients were divided into the IOM peeling group(49eyes i and non-ILM peeling group(65eyes i,according to whether or not the OM was removed during vitrectomy.Alt patients underwent23g vitrectomy combined with silicone oii tamponade,and silicone oii removvi was peWormed at3〜5months after the sumem•The patients were reexamined before operaUon and at1,3,6and12months after vitrectomy.The best corrected visual acuity(BCVA)and macular microstruc­tures,i/cluPing central retinal thich/ess(CRT),egipsoia zone(EZ),external limiting membrane(ELM)conU/uity , macular edema and subreU/ai UPP(SRF)were compared between the two awups.Resalts s Among114eyes,ERM was formed in12eyes(4eyes in the OM peeling group and15eyes in non-ILM peeing group),and94.7%of ERM occurred within6months fter the sumem•The prevvlenco of ERM formation was sipnificanUy higher in the non-ILM peeing group than the OM peeling group at3,6and12months after the suraem(P<0.45).The BCVA of the two groups at1,3,6 and12months after the surgerg was significanUy better than that before the surgee,and the diRerenco was stanstically sig­nificant(P<0.05).There was no significant diRerenco in BCVA at diRere/t Ume points after the surgee，The BCVA for parUcipants with ERM and without ERM was(0.59±0.51and0.31±0.68),respectiveA with swtistically significant diRerenco(h=-2.331,P<0.45).No difference was ohserved in CRE ,EZ ,ELM conU/uity,macular edema or SRF between the two geups.Conclusions PeahyActic OM peeling can effectively prevent the occurrence of ERM formationDOI：12.3969//imu.J206-C420.420/71.725基金项目：保定市科技计划自筹经费项目（1241ZF243）作者单位：河北省保定市第一中心医院眼二科778007通讯作者:顾朝辉（Email:zhaQhui-gu@）after RRD and has no eCect on visucl acuip and retina-micestectpe.【Key worht】RheymaWgecous reU/ai deWchmects: EpireC/ai membrane;Internai limiting membrane peeling;Best corrected visual acuity；Vitrectomy[J CUn Ophthalmol,2021,29：20]临床眼科杂志2021年第29卷1期Jpanal P CAnical OphthdAoAay,2021‘VoU29,No.1・21・黄斑前膜(sieU—i membenv,ERM)形成是孔源性视网膜脱离(rUeymaWgexoas retinai detach­meat,RRD)术后较常见并发症之一［］,ERM形成可引起视力下降、视物变形，是患者术后视觉功能恢复不理想的常见原因［］。

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Effect of Sn addition on the microstructure and mechanical properties of Mg–6Zn–1Mn (wt.%)alloyFugang Qi a ,⇑,Dingfei Zhang b ,c ,Xiaohua Zhang a ,Xingxing Xu b ,caChina Academy of Engineering Physics,Mianyang 621900,PR ChinabCollege of Materials Science and Engineering,Chongqing University,Chongqing 400045,PR China cNational Engineering Research Center for Magnesium Alloys,Chongqing University,Chongqing 400044,PR Chinaa r t i c l e i n f o Article history:Received 23June 2013Received in revised form 21September 2013Accepted 24September 2013Available online 11October 2013Keywords:Mg–Zn Mg–Sn PrecipitateMechanical propertiesa b s t r a c tThe microstructure and mechanical properties of Mg–6Zn–1Mn alloys with varying Sn contents (0,1,2,4,6,8and 10wt.%)have been examined using optical microscopy (OM),X-ray diffractometer (XRD),scan-ning electron microscopy(SEM),transmission electron microscopy (TEM),hardness test and uniaxial ten-sile test at room temperature,respectively.The samples were prepared by hot-extrusion after casting.The results showed that the as-cast Sn-containing alloys consisted of a -Mg,Mg 7Zn 3,Mn and Mg 2Sn phases.T6treatments could obviously improve the strengths of the as-extruded samples,and the double aged samples exhibited enhanced age-hardening response at an earlier stage compared to the single aged ones.Among them,the 4wt.%Sn containing sample with double peak aging after solution treatment had the highest strengths and moderate elongation.Microstructure characterization indicated that the high-strengths of the peak aged alloys were mainly determined by a synergistic effect on precipitation strengthening of b 01(MgZn 2)and Mg 2Sn precipitates,and the precipitates after double aging were finer than those after single aging.Ó2013Elsevier B.V.All rights reserved.1.IntroductionMagnesium alloys have wide applications in the aerospace,transportation and mobile electronics industries due to their advantages such as low density,high specific strength and stiff-ness,good damping capacity,excellent machinability and good castability [1–4].However,the application of magnesium alloys is still very limited due to the inadequate strength,poor formabil-ity,and high cost of either expensive alloying elements used or special processing technology involved [5–7].Therefore,it is press-ing to develop some low cost and high strength wrought magne-sium alloys for wider applications.Mg–Zn system alloys,which are the most widely used wrought magnesium alloys,have more pronounced response to age harden-ing compared to other magnesium alloys [8–11].The studies on age-hardening and microstructure in this Mg–Zn alloy have been carried out since 1960s [8,9,11–15],and the precipitation sequence from a supersaturated solid solution (SSSS)during aging were re-ported to be [8,9,15,16]:SSSS ?GP zones ?b 01rods,blocks \{0001}Mg ;(MgZn 2)?b 02discs ||{0001}Mg ;laths \{0001}Mg ;(MgZn 2)?b (MgZn or Mg 2Zn 3).Recently,Mg–6Zn–1Mn (wt.%)(ZM61)alloy (hereafter,all compositions are in weight percentsunless stated otherwise),a new promising high-strength magne-sium alloy,has attracted attention due to good castability,excel-lent formability and significant precipitation hardening response [17–20].In our previous study,we reported that T6treatments,especially double aging,could significantly improve the mechani-cal properties of the as-extruded ZM61alloy [17,18].The high-strengths of peak aged ZM61alloy are associated with the precipitation of the rod-shaped transition b 01phase,and double aging promotes the precipitation of b 01phase.Further,the micro-structure and mechanical properties of Mg–x Zn–1Mn alloy were reported [19,20].Accordingly,the Mg–6Zn–1Mn alloy had the best comprehensive mechanical properties.In addition,Mg–Sn alloys are also known as a precipitation-hardening system,which has a relatively high solubility (14.48wt.%)at about 561°C and low solubility at ambient temper-ature [21,22].However,since the Mg 2Sn precipitates forms with a lath-shaped morphology on the (0001)Mg basal planes of the ma-trix,the precipitation hardening response for the Mg–Sn binary al-loy is low [23].Moreover,the peak hardness of Mg–Sn binary alloy occurs after long-term aging,which is not practical for industrial application [23].Sasaki et al.[24–26]reported that a minor addition of Zn can enhance the age-hardening response of the binary alloy by the homogeneous dispersion of the precipitates.It is of great inter-est to explore the possible cumulative effects on precipitation strengthening of MgZn 2and Mg 2Sn precipitates,so as to develop0925-8388/$-see front matter Ó2013Elsevier B.V.All rights reserved./10.1016/j.jallcom.2013.09.156Corresponding author.Tel.:+868163626782.E-mail address:fugangqi@ (F.Qi).1.XRD patterns of the as-cast Mg–6Zn–1Mn–x Sn(x=0,1,2,4,6,8andalloys(the red arrows in thefigure indicate that the intensifying tendency of Mgphase diffraction peak).(For interpretation of the references to colour in thisfigurelegend,the reader is referred to the web version of this article.)micrographs of the as-cast Mg–6Zn–1Mn–x Sn alloys.(a)x=0,(b)x=1,(c)x=2,(d)x=4,(e)x=6,(f)x=as-cast(a)Mg–6Zn–1Mn and(b)Mg–6Zn–1Mn–4Sn alloys,and(c and d)corresponding EDS results of the as-homogenized Mg–6Zn–1Mn–x Sn alloys.(a)x=0,(b)x=1,(c)x=2,(d)x=4,(e)ZG-0.01vacuum induction melting furnace under an Ar atmosphere.The actual chemical compositions of the experimental alloy ingots were analyzed by XRF-800CCDE X-rayfluorescence spectrometer,and the results are shown in Table1. The ingots were then homogenized at330°C for24h followed by the air cooling.Before the ingots were extruded,both the alloy ingots and extrusion die were heated to350°C for60min.The ingots were extruded at350°C with an extrusion ratio of25and a ram speed of2mm/s.Extrusion was conducted under a controlled constant force by a XJ-500Horizontal Extrusion Machine.After extrusion,the extru-sion bars were cooled in open air.Then the extruded bars were solution-treated at 440°C for2h in air atmosphere followed by water quenching(T4).After solution treatment,the following artificial aging treatments(T6)would be divided into sin-gle aging and double aging,respectively.The single aging was carried out at180°C, and the double aging was carried out by pre-aging at90°C for24h,followed by the secondary aging at180°C.Hardness measurements were performed by a micro-Vickers apparatus under a load of50g.The mechanical properties of the as-extruded,single peak aged(180°C/12h) and double peak aged(90°C/24h+180°C/8h)samples were evaluated by tensile tests at room temperature.Tensile tests were carried out using a SANS CMT-5105 electronic universal testing machine.Samples for tensile tests had a cross-sectional diameter of5mm and a gauge length of60mm.the tensile axis paralleled to extru-sion direction and the tests were performed at a cross-heat speed of3mm/min at room temperature.Mechanical properties were determined from a complete 3.Results and discussion3.1.As-cast and as-homogenized microstructuresThe XRD analysis results of the as-cast Mg–6Zn–1Mn alloys with different Sn contents are shown in Fig.1.It can be seen that the Mg–6Zn–1Mn alloy consists of a-Mg,Mg7Zn3and Mn phases, while the alloys with Sn additions consists of four phases,i.e.,a-Mg,Mg7Zn3,Mn and Mg2Sn.It is also evident that the intensity of the Mg2Sn peaks increase with the increasing Sn content.Fig.2shows the optical microstructures of the as-cast alloys with different Sn contents.As shown in Fig.2,the coarse dendritic structure of the as-cast Mg–6Zn–1Mn alloy is generally refined after the Sn addition.The microstructure of the Sn-free alloy mainly consists of a-Mg and eutectic Mg7Zn3phases at the grain boundaries.The addition of Sn leads to the formation of the eutec-tic Mg2Sn phases at the grain boundaries.Furthermore,withHAADF–STEM micrographs of the as-homogenized(a)Mg–6Zn–1Mn and(b and c)Mg–6Zn–1Mn–4Sn alloys,and(d)F.Qi et al./Journal of Alloys and Compounds585(2014)656–666659bright phases includes Mg,Sn and Mn.The bright phase is likely the Mg2Sn phase because the Mg/Sn(in at.%)ratio is approximately 2:1.Fig.4shows the optical microstructure of the as-homogenized alloys with different Sn contents.Discontinuous secondary phases disperse in the alloys,and the secondary phases are identified by means of SEM and EDS.Fig.5a shows the BSE image of the Sn-free 3.2.As-extruded and solution-treated microstructuresMicrostructural changes after the hot extrusion are shown in Figs.6and7.Owing to the deformation and the occurrence of dynamic recrystallization(DRX)during the hot extrusion process, the undissolved blocky eutectic compounds after homogenization treatment are further broken into small particles,which distrib-as-extruded Mg–6Zn–1Mn–x Sn alloys(the extruded direction is horizontal).(a)x=0,(b)x=1,(c)x= 660 F.Qi et al./Journal of Alloys and Compounds585(2014)656–666solution-treated sample consists of a -Mg matrix and Mn phases.For the alloys with Sn content of less than 4%and more than 0%,almost all the secondary phase particles dissolve into the matrix as same as the Sn-free alloy.However,with further increasing Sn content,a lot of undissolved compounds are remained in the matrix.The XRD pattern of the solution-treated Mg–6Zn–1Mn–4Sn alloy is shown in Fig.9d.It is obvious that the solution-treated sample consists of a -Mg matrix,Mn and Mg 2Sn phases.Fig.10a and b shows the BSE and bright-field TEM micrographs in detail of the solution-treated Mg–6Zn–1Mn–4Sn alloy.From the Fig.10,only one spherical phase can be observed.The sizes of these spherical particles range from 10to 70nm,which are randomly distributed within the a -Mg matrix.In addition,No other phases are seen within the a -Mg matrix after solution treatment.Based on XRD result and EDS analysis,we can conclude that the spherical phase is pure Mn particle.3.3.Age-hardening behaviors and peak-aged microstructures Fig.11shows the age-hardening curves of the solution-treated Mg–6Zn–1Mn–x Sn alloys subjected to single aging at 180°C and double aging at 180°C (pre-aging at 90°C for 24h).During the sin-gle aging at 180°C,the hardness of the Mg–6Zn–1Mn alloy in-creases with aging time and reaches a peak hardness after about 12h.The age-hardening curve of the Mg–6Zn–1Mn–4Sn alloy is very similar to that of the Mg–6Zn–1Mn alloy during the single aging,and the time to reach peak hardness is relatively unaffected by the Sn addition.However,the peak hardness increases from 74Hv to 82Hv by increasing the Sn content from 0%to 4%.A slight increase in the hardness for the Mg–6Zn–1Mn alloy is observed by double aging.The peak hardness increases to 85Hv in 8h after starting the secondary aging.The time to reach the peak hardness,8h,is slightly shorter than that for the single aging,12h.Like sin-gle aging,the age-hardening curves of the quaternary alloys are very similar to those of the ternary alloy during the double aging,and the time to reach peak hardness is relatively unaffected bythe Sn addition.Moreover,the peak hardness values increase grad-ually with increasing Sn content.The base hardness for the alloys containing no more than 4%Sn is about 60Hv,while the base hard-ness of the alloys containing more than 4%Sn increases gradually with increasing Sn addition.As mentioned above,almost all the secondary phases for the alloys containing no more than 4%Sn dis-solve into the matrix after solution treatment,while a lot of undis-solved compounds for the alloys containing more than 4%Sn are still remained in the matrix.This suggests that these undissolved compounds after solution treatment mainly contribute to the in-crease of the base hardness.Fig.9b and c and e and f shows the XRD patterns of the Mg–6Zn–1Mn and Mg–6Zn–1Mn–4Sn alloys in single peak aged and double peak aged conditions.As mentioned previously,for the two alloys almost all the Mg–Zn and/or Mg 2Sn phases dissolve into the Mg matrix after solution treatment,which suggests that the uniform solid-solution structure is produced.After T6treatments,MgZn 2precipitates are formed in the Mg–6Zn–1Mn alloy,while the 4%Sn addition bring about the formation of Mg 2Sn precipitates as well as MgZn 2phases as illustrated by XRD patterns.Generally,the MgZn 2precipitation relates to the peak hardness in the Sn-free alloy;while the Sn-containing alloys show a greater magnitude aging response due to a larger amount of precipitations resulting from the Sn addition.Fig.12shows a bright-field TEM and a high resolution TEM (HR–TEM)images of the Mg–6Zn–1Mn–4Sn alloy aged at 90°C for 24h,taken from the [0001]Mg zone axis.This corresponds to the pre-aged condition of the double aging.From the Fig.12a,it can be observed that a number of fine particles ( 9nm)having dark contrast are evenly dispersed in the matrix.The HR–TEM im-age shows a spherical precipitate having 9nm in size in Fig.12b.Clear lattice contrast cannot be seen inside the particle.According to the previous reports [8,27],we can conclude that these fine par-ticles are G.P.zones.Fig.13shows the TEM images of the Mg–6Zn–1Mn–4Sn alloy in single peak aged (180°C/12h)and double peak aged (180°C/8h)(SE)micrographs of the as-extruded (a)Mg–6Zn–1Mn and (b)Mg–6Zn–1Mn–4Sn alloys (the extruded direction of the points indicated in (a and b).conditions.All images are obtained from Fig.13a and b shows the bright-field TEM jected to peak aging by single aging and In both conditions,the microstructure after ner than those after single peak aging.1Mn–4Sn samples have three kinds of Fig.13.One is rod along the [0001]direction second is lying on the (0001)basal plane.studies [8,15,28,29],we can conclude are rod-like b 01and disc-like b 02phases,between the b 01and matrix is coherent,between the b 02and matrix.Therefore as a more enormous impediment to than the b 02precipitate [27].The third is common morphology.In this work,some tates are flaky-like.Fig.13b shows a HR–TEM Mg 2Sn precipitate observed in the single Fourier transform (FFT)pattern obtained taken from the ½11 20 zone axis.Through can be preliminary found that the micrographs of the solution-treated Mg–6Zn–1Mn–x Sn alloys.(a)x =0,(b)x =1,(c)x =2,(d)x =4,(e)x =6,(f)9.XRD patterns of the (a–c)Mg–6Zn–1Mn and (d–f)Mg–6Zn–1Mn–4Sn alloys different states.(a and d)solution-treated,(b and e)Single peak aged at 180°C 12h,and (c and f)double peak aged at 180°C for 8h.[001]Mg2Sn//½11 20Mgand no clear orientation relationshipobserved.It can be concluded there is a certain angle between this Mg2Sn and base level[0001]Mg,otherwise this Mg2Sn phase is ob-served as a rod through the½11 20Mgview direction.Based on the previous studies[21,26],this Mg2Sn precipitate may be parallel to the prismatic plane of the magnesium matrix. many other irregular-shaped Mg2Sn precipitates, is needed to discuss the orientation relationship tates since the reason for this still remains As previously stated,a number of G.P.pre-aging condition.G.P.zones are believed neous nucleation sites for the transitionhigh temperature aging,leading to thetribution offiner precipitates.In addition,like phase for Mg2Sn phase during theand the times to reach the peak hardnessof double peak aging are much shorter than aging,so Mg2Sn precipitates of the doublefiner than those of the single peak agedpeak hardness of the double peak agedthose of single peak aged ones.Furthermore, precipitate b01and b01precipitates occursble peak aged samples than the singleage-hardening is accelerated.In addition,it can be seen that many dispersed in the matrix,which are founditates but not found in disc-like b02precipitates,solution-treated Mg–6Zn–1Mn–4Sn alloy.(a)BSE micrograph and(b)bright-field TEM micrograph,takendiffraction pattern).Fig.11.Age-hardening curves of the Mg–6Zn–1Mn–x Sn(x=0,2,4,6,8and10)alloys subjected to single aging at180°C and double aging at180°C(pre-aging at90°C for24h and secondary aging at180°C).Fig.12.(a)Bright-field and(b)high resolution TEM micrographs of the Mg–6Zn–1Mn–4Sn alloy aged at90°C for24h,taken from3.4.Mechanical propertiesFig.14shows the mechanical properties of the test alloys in the as-extruded,single peak aged (180°C/12h)and double peak aged (90°C/24h +180°C/8h)conditions.It can be seen that Sn addition has a beneficial effect on the mechanical properties of the Mg–6Zn–1Mn alloy.For the as-extruded alloys,the ultimate tensile strength (UTS)and yield strength (YS)increase gradually with increasing Sn content.The alloy containing 4%Sn has the best strengths,i.e.,an UTS of 331MPa and a YS of 272Mpa,which are superior to the commercial high-strength ZK61with an UTS of 305MPa and a YS of 240MPa [30].However,the excessive Sn addi-tion (>4%)results in the decrease of the elongation.As shown in Fig.14,T6treatments result in large increases in the strengths of all the investigated alloys compared to the as-extruded ones.On one hand,with increasing Sn content,the elongation decreases gradually while the UTS and YS significantly increase,and the maximum of the UTS and YS is obtained for the alloy containing 4%Sn.Further increasing Sn content results in a slight reduction of the UTS and YS in the peak-aged conditions.On the other hand,the strengths of the double peak aged samples are higher than that of the single peak aged ones,while the elonga-tions are slightly lower.The mechanical properties of the double peak aged Mg–6Zn–1Mn–4Sn alloy are an UTS of 390MPa,a YS of 378MPa and an elongation of 4.16%,while those of the single peak aged sample are an UTS of 379MPa,a YS of 358MPa and an elongation of 4.24%.These strengths are comparable to those of some T5-treated or T6treated RE-containing magnesium alloys,including Mg–Gd–Y–Zn–Zr [31],Mg–Gd–Y–Nd–Zr [32]and Mg–Y–Sm–Zr [33].The high-strengths of the Mg–Zn–Mn–Sn wrought alloys are mainly determined by grain refinement strengthening and precip-itation strengthening.It is well-known that strengthening via grain size control is particularly effective in magnesium alloys because of the higher Hall–Petch coefficient [34].The strengths of the as-extruded alloys are strongly influenced by the relatively fine grains with an average size of approximately 2.8l m.As shown in Fig.14,the strengths of the as-extruded samples are improved signifi-cantly by the T6aging treatments.After T4treatment,almost all the Mg–Zn and Mg–Sn compounds in the as-extruded alloys with no more than 4%Sn can dissolve into the matrix,which suggests that a uniform and supersaturated solid-solution structure is produced,as shown in Figs.8and 10.Aging the solution-treated samples is necessary so that the fine b 01,b 02and Mg 2Sn precipitates form within the matrix.The precipitate particles act as obstacles to dislocation movement and thereby strengthening the aged alloy.However,when the content of Sn exceeds 4%,some compounds cannot dissolve into the matrix after solution treatment.At subse-quent aging,these undissolved compounds in the matrix will lead to the decrease of the mechanical properties,while they can con-tribute to the increase of the base hardness,resulting in the in-creased hardness values with increasing Sn content.Moreover,the peak hardness of the double peak aged samples is higher than those of the single peak aged ones and the double aging achieves finer microstructure than the single aging,so the strengths of the double aged samples are higher than that of the single agedones.peak aged Mg–6Zn–1Mn–4Sn alloy.(a)Bright-field TEM image of the single peak aged at 180°C for 12h,pattern),(b)HR–TEM image of a Mg 2Sn phase observed in the single peak aged (inset:FFT pattern obtained aged at 180°C for 8h,taken along the ½11 20 zone axis (inset:½11 20 Mgdiffraction pattern)and (d)HAADF–STEM4.ConclusionThe microstructure evolution and mechanical properties of the Mg–6Zn–1Mn–x Sn (x =0,1,2,4,6,8and 10wt.%)alloys subjected to extrusion,single aging and double aging have been investigated by hardness measurements,tensile tests and microstructureanalysis using SEM,XRD and TEM.The following conclusions are obtained:1.The as-cast Mg–6Zn–1Mn alloy mainly consists of a -Mg,Mg 7Zn 3and Mn phases.Sn addition results in the formation of Mg 2Sn phase and the refinement of the eutectic.2.The addition of Sn can clearly improve the mechanical proper-ties of the as-extruded Mg–6Zn–1Mn alloy due to grain refine-ment strengthening.In more detail,with increasing Sn content,the strengths increase gradually while the elongation decreases gradually.3.T6treatments,especially double aging,can markedly improve the strengths of the as-extruded investigated alloys.Among them,the Mg–6Zn–1Mn–4Sn alloy with double peak aging after solution treatment exhibits the highest tensile strength of 390MPa,the highest yield strength of 378MPa and the moder-ate elongation of4.16%.4.The microstructure characterization suggests that the high-strengths of the peak aged alloys are mainly determined by a synergistic effect on precipitation strengthening of the b 01and Mg 2Sn precipitates,and the precipitates of the double aged samples are finer than those of the single aged ones.AcknowledgementsThis work was sponsored by National Great Theoretic Research Project (2007CB613700),National Science &Technology Support Project (2011BAE22B01-3),International Cooperation Project (2010DFR50010,2008DFR50040),Chongqing Science &Technol-ogy Project (2010CSTC-HDLS)and Chongqing Science &Technol-ogy Commission (CSTC2013JJB50006).References[1]A.A.Luo,Int.Mater.Rev.49(2004)13–30.[2]D.Eliezer,E.Aghion,F.H.Froes,Adv.Perform.Mater.5(1998)201–212.[3]J.Wang,S.Gao,P.Song,X.Huang,Z.Shi,F.Pan,J Alloys Comp.509(2011)8567–8572.[4]W.Unsworth,Light Metal Age 45(1987)10–13.[5]Y.Kawamura,K.Hayashi,A.Inoue,T.Masumoto,Mater.Trans.42(2001)1172–1176.[6]D.F.Zhang,H.J.Hu,F.S.Pan,M.B.Yang,J.P.Zhang,Trans.Nonferr.Met.Soc.20(2010)478–483.[7]X.Cao,M.Jahazi,J.P.Immarigeon,W.Wallace,J.Mater.Process.Technol.171(2006)188–204.[8]J.B.Clark,Acta Metall.13(1965)1281–1289.[9]L.Y.Wei,G.L.Dunlop,H.Westengen,Metall.Mater.Trans.A 26A (1995)1705–1716.[10]D.Y.Maeng,T.S.Kim,J.H.Lee,S.J.Hong,S.K.Seo,B.S.Chun,Scripta Mater.43(2000)385–389.[11]J.Chun,J.Byrne,J.Mater.Sci.4(1969)861–872.[12]G.Mima,Y.Tanaka,Mem Fac.Eng.23(1962)93.[13]G.Mima,Y.Tanaka,Aging 1(1971)10.[14]G.Mima,Y.Tanaka,Trans.JIM 12(1971)323–328.[15]X.Gao,J.F.Nie,Scripta Mater.56(2007)645–648.[16]J.Buha,T.Ohkubo,Metall.Mater.Trans.A 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Key to Exerc‎i se Unit 1 Chemi‎c al Indus‎t ries‎1.the Indus‎t rial‎Revol‎u tion‎an‎i c chemi‎c als3.the conta‎c t proce‎s s4.the Haber‎proce‎s s5.synth‎e tic polym‎e rs6.inter‎m edia‎t es7.artif‎i cial‎ferti‎l izer‎s 8.pesti‎c ides‎9.synth‎e tic fiber‎s10.pharm‎a ceut‎i cal11.resea‎r ch and devel‎o pmen‎t12.petro‎c hemi‎c alpu‎t ers14.capit‎a l inten‎s iveSome Chemi‎c als Used In Our Daily‎LifeFood artif‎i cial‎ferti‎l izer‎s, pesti‎c ide, veter‎i nary‎produ‎c ts Healt‎h antib‎i otic‎s, β-block‎e rsCloth‎i ng synth‎e tic fiber‎s (e.g. polye‎s ters‎, polya‎m ides‎),synth‎e tic dyesShelt‎e r synth‎e tic polym‎e rs (e.g. urea-forma‎l dehy‎d e,polyu‎r etha‎n es),plast‎i csLeisu‎r e plast‎i cs and polym‎e rs (e.g. nylon‎)Trans‎p ort addit‎i ves (e.g. anti-oxida‎n ts, visco‎s ity index‎impov‎e ment‎s),polym‎e rs, plast‎i csUnit 2 Resea‎r ch and Devel‎o pmen‎t1.R&D2.ideas‎and knowl‎e dge3.proce‎s s and produ‎c ts4.funda‎m enta‎l5.appli‎e d6.produ‎c t devel‎o pmen‎t7.exist‎i ng produ‎c t8.pilot‎plant‎9. a emerg‎i ng case10.envir‎o nmen‎t al impac‎t11.energ‎y cost 12.techn‎i cal suppo‎r t13.proce‎s s impro‎v emen‎t14.efflu‎e nt treat‎m ent15.pharm‎a ceut‎i cal16.suffi‎c ient‎l y pure17.React‎i on18.unrea‎c ted mater‎i al19.by-produ‎c ts20.the produ‎c t speci‎f icat‎i on21.Produ‎c t stora‎g eUnit 3 Typic‎a l Activ‎i ties‎of Chemi‎c al Engin‎e ers1.Mecha‎n ical‎2.elect‎r ical‎3.civil‎4.scale‎-upme‎r cial‎-size6.react‎o rs7.disti‎l lati‎o n colum‎n s8.pumps‎9.contr‎o l and instr‎u ment‎a tion‎10.mathe‎m atic‎s11.indus‎t ry12.acade‎m ia13.steam‎14.cooli‎n g water‎15.an econo‎m ical‎16.to impro‎v e17.P&I Drawi‎n gs18.Equip‎m ent Speci‎f icat‎i on Sheet‎s19.Const‎r ucti‎o n20.capac‎i ty and perfo‎r manc‎e21.bottl‎e neck‎s22.Techn‎i cal Sales‎23.new or impro‎v ed24.engin‎e erin‎g metho‎d s25.confi‎g urat‎i onsUnit 4 Sourc‎e s of Chemi‎c als1.inorg‎a nic chemi‎c als2.deriv‎e from3.petro‎c hemi‎c al proce‎s ses4.Metal‎l ic ores5.extra‎c tion‎proce‎s s6.non-renew‎a ble resou‎r ce7.renew‎a ble sourc‎e s8.energ‎y sourc‎e9.ferme‎n tati‎o n proce‎s s10.selec‎t ive 11.raw mater‎i al12.separ‎a tion‎and purif‎i cati‎o n13.food indus‎t ry14.to be wette‎d15.Key to succe‎s s16.Crush‎i ng and grind‎i ng17.Sievi‎n g18.Stirr‎i ng and bubbl‎i ng19.Surfa‎c e activ‎e agent‎s20.Overf‎l owin‎gUnit 5 Basic‎Chemi‎c als1.Ethyl‎e ne2.aceti‎c acid3.Polym‎e riza‎t ion4.Polyv‎i nyl aceta‎t e5.Emuls‎i on paint‎High-volum‎e secto‎r Low-volum‎e secto‎rProdu‎c tion‎scale‎tens to hundr‎e ds of thous‎a ndstons per yeartens to a few thous‎a nds tonsper yearProdu‎c ts / a plant‎singl‎e produ‎c t multi‎-produ‎c ts Opera‎t ion manne‎r conti‎n uous‎batch‎Price‎or profi‎t fairl‎y cheap‎very profi‎t able‎Usage‎inter‎m edia‎t es end-produ‎c tsChall‎e nges‎reduc‎e d deman‎d, envir‎o nmen‎t pollu‎t ionProdu ‎c ts in the secto ‎r sulph ‎u ric acid,phosp ‎h orus ‎-conta ‎i ning ‎compo ‎u nds, nitro ‎g en-conta ‎i ning ‎ compo ‎u nds, chlor ‎-alkal ‎i , petro ‎c hemi ‎c als, commo ‎d ity polym ‎e rsagroc ‎h emic ‎a ls,dyest ‎u ffs, pharm ‎a ceut ‎i cals ‎, speci ‎a lity ‎ polym ‎e rsUnit 6 Chlor ‎-Alkal ‎i and Relat ‎e d Proce ‎s ses 1. Ammon ‎i a 2. ammon ‎i a absor ‎b er 3. NaCl & NH4OH ‎ 4. Carbo ‎n dioxi ‎d e5. NH4Cl ‎6. Rotar ‎y drier ‎7. Light ‎ Na2CO ‎38. Water ‎ Produ ‎c tRaw mater ‎i alMajor ‎ steps ‎ or Princ ‎i pal react ‎i ons UsesSoda-ashbrine ‎,limes ‎t oneammon ‎i atin ‎g ,carbo ‎n atin ‎g , preci ‎p itat ‎i ng, filte ‎r ing, dryin ‎g , calci ‎n ingraw mater ‎i al forglass ‎m akin ‎g , sodiu ‎m silic ‎a te; as an alkal ‎i Chlor ‎i ne brine ‎2Na + + 2Cl -+2H 2O →NaOH +Cl 2 +H 2as water ‎ purif ‎i cati ‎o n, bleac ‎h ing of wood pulp;produ ‎c tion ‎ of vinyl ‎ chlor ‎i de, solve ‎n ts,inorg ‎a nic chlor ‎i ne-conta ‎i ning ‎produ ‎c ts Caust ‎i c soda brine ‎2Na + + 2Cl - +2H 2O →NaOH +Cl 2 +H 2for paper ‎-makin ‎g ,manuf ‎a ctur ‎e of inorg ‎a nicchemi ‎c als, synth ‎e ses of organ ‎i cchemi ‎c als,produ ‎c tion ‎ of alumi ‎n a andsoap Sulfu ‎r ic acideleme ‎n tal sulph ‎u rS +O 2 → SO 2SO 2 + O 2 → SO 3 SO 3 + H 2O → H2SO4‎feeds ‎t ock for ferti ‎l izer ‎s ; produ ‎c tion ‎ of ethan ‎o l, hydro ‎f luor ‎i c acid, alumi ‎n um sulph ‎a tesUnit 10 What Is Chemi ‎c al Engin ‎e erin ‎gMicro ‎s cale ‎ (≤10-3m) ● Atomi ‎c and molec ‎u lar studi ‎e s of catal ‎y sts● Chemi ‎c al proce ‎s sing ‎ in the manuf ‎a ctur ‎e of integ ‎r ated ‎ circu ‎i ts ●Studi ‎e s of the dynam ‎i cs of suspe ‎n sion ‎s and micro ‎s truc ‎t ured ‎ fluid ‎sMesos ‎c ale (10-3－102m)●Impro‎v ing the rate and capac‎i ty of separ‎a tion‎s equip‎m ent●Desig‎n of injec‎t ion moldi‎n g equip‎m ent to produ‎c e car bumpe‎r s madefrom polym‎e rs●Desig‎n ing feedb‎a ck contr‎o l syste‎m s for biore‎a ctor‎sMacro‎s cale‎(>10m)●Opera‎b ilit‎y analy‎s is and contr‎o l syste‎m synth‎e sis for an entir‎e chemi‎c alplant‎●Mathe‎m atic‎a l model‎i ng of trans‎p ort and chemi‎c al react‎i ons ofcombu‎s tion‎-gener‎a ted air pollu‎t ants‎●Manip‎u lati‎n g a petro‎l eum reser‎v oir durin‎g enhan‎c ed oil recov‎e rythrou‎g h remot‎e sensi‎n g of proce‎s s data, devel‎o pmen‎t and use of dynam‎i cmodel‎s of under‎g roun‎d inter‎a ctio‎n s, and selec‎t ive injec‎t ion of chemi‎c alsto impro‎v e effic‎i ency‎of recov‎e ryCours‎e Cours‎e conte‎n tScien‎c e and Math. Chemi‎s try, Physi‎c s, Biolo‎g y, Mater‎i al Scien‎c e, Mathe‎m atic‎s,Compu‎t er Instr‎u ctio‎nChemi‎c al Engin‎e erin‎gTherm‎o dyna‎m ics, Kinet‎i cs, Catal‎y sis,Recto‎r Desig‎n and Analy‎s is, Unit Opera‎t ions‎, Proce‎s s Contr‎o l, Chemi‎c al Engin‎e erin‎g Labor‎a tori‎e s, Desig‎n / Econo‎m icsOther‎ENGIN‎e erin‎g Elect‎r ical‎Engin‎e erin‎g, Mecha‎n ics, Engin‎e erin‎g Drawi‎n gHuman‎i ties‎and Socia‎lSCIEN‎c e Under‎s tand‎the origi‎n s‎of‎one’s‎own‎cultu‎r e as well as that ofother‎sUnit 21 Chemi‎c al Indus‎t ry and Envir‎o nmen‎t1.ATMOS‎p heri‎c chemi‎s try2.strat‎o sphe‎r ic ozone‎deple‎t ion3.acid rain4.envir‎o nmen‎t ally‎frien‎d ly produ‎c ts5.biode‎g rada‎b le6.harmf‎u l by-produ‎c t7.effic‎i entl‎y8.power‎plant‎emiss‎i ons9.diffe‎r ent plast‎i cs10.recyc‎l ed or dispo‎s ed11.acidi‎c waste‎solut‎i onsan‎i c compo‎n ents‎13.membr‎a ne techn‎o logy‎14.biote‎c hnol‎o gy15.micro‎o rgan‎i smsFront‎i er Resea‎r ch activ‎i ties‎or probl‎e ms faced‎In-site proce‎s sing‎Field‎tests‎;Uncer‎t aint‎i es of the proce‎s s, Adver‎s e envir‎o nmen‎t impac‎t sProce‎s s solid‎sImpro‎v e solid‎s fract‎u re proce‎s ses,Resea‎r ch on the mecha‎n ics of pneum‎a tic and slurr‎y trans‎p ort, Under‎s tand‎the chemi‎c al react‎i on proce‎s ses,Equip‎m ent desig‎n and scale‎-upSepar‎a tion‎proce‎s sResea‎r ch on:membr‎a ne separ‎a tion‎s, chemi‎c al selec‎t ive separ‎a tion‎agent‎s, shape‎-selec‎t ive porou‎s solid‎s,tradi‎t iona‎l separ‎a tion‎metho‎d sMater‎i alsFind const‎r ucti‎o n mater‎i als, Devel‎o p new proce‎s s-relat‎e d mater‎i als, Devel‎o p less energ‎y inten‎s ive mater‎i alsDesig‎n and scale‎-up Compl‎e xity‎, Lack of basic‎data,。

第39卷 第6期 陕西科技大学学报 V o l.39N o.6 2021年12月 J o u r n a l o f S h a a n x iU n i v e r s i t y o f S c i e n c e&T e c h n o l o g y D e c.2021* 文章编号:2096-398X(2021)06-0039-06凉皮(面皮)贮藏过程中的回生行为及其机理黄峻榕,伏佳静,蒲华寅,马珂莹,邝吉卫(陕西科技大学食品与生物工程学院,陕西西安 710021)摘 要:凉皮是西北地区的特色风味小吃.在贮藏过程中其品质变化机理尚不清楚,成为制约凉皮工业化的瓶颈问题.以小麦淀粉为原料制作凉皮,在4℃分别贮藏0d㊁1d㊁3d㊁5d㊁7d,对凉皮的水分含量㊁质构特性㊁微观结构㊁结晶特性㊁热学特性㊁短程有序结构进行分析.结果表明:凉皮在0~7d的储存过程中水分含量从33.17%降至28.54%,硬度从169.83g增大至294.38g,咀嚼性从61.37增加至118.51,微观结构由光滑的网络状结构变为粗糙㊁疏松多孔结构;淀粉的短程有序度从0.51增大至1.07,晶型逐渐从A-型向B-型转变,且相对结晶度从2.1%增大至16.8%,回生焓从3.02J/g增大至3.92J/g.在贮藏过程中,淀粉分子之间通过氢键形成螺旋结构,分子的短程有序度增大;螺旋结构规则堆积形成结晶,且数量不断增大,使得淀粉的持水力下降,硬度增大,网络结构出现塌陷和断裂,表现为凉皮回生程度逐渐增大.研究发现了凉皮贮藏品质下降规律及变化机理,为提高凉皮的品质稳定性提供了理论基础.关键词:凉皮;淀粉回生;结晶度;有序结构中图分类号:T S236 文献标志码:AR e t r o g r a d a t i o nb e h a v i o r a n dm e c h a n i s m s o fL i a n g p i(M i a n p i)d u r i n g s t o r a g eHU A N GJ u n-r o n g,F UJ i a-j i n g,P U H u a-y i n,MA K e-y i n g,K U A N GJ i-w e i (S c h o o l o fF o o d a n dB i o l o g i c a l E n g i n e e r i n g,S h a a n x iU n i v e r s i t y o f S c i e n c e&T e c h n o l o g y,X i'a n710021,C h i-n a)A b s t r a c t:L i a n g p i i sas p e c i a l s n a c ki n N o r t h w e s tC h i n a.T h e m e c h a n i s m o f q u a l i t y c h a n g ed u r i n g s t o r a ge i s n o t c l e a r,w h i c hh a s b e c o m e a b o t t l e n e c k p r o b l e mr e s t r i c t i n g t h e i n d u s t r i a l i-z a t i o no fL i a n g p i.L i a n g p iw a sm a d eb y w h e a t s t a r c ha s r a w m a t e r i a l,a n ds t o r e da t4℃f o r 0,1,3,5a n d7d a y s,r e s p e c t i v e l y.T h em o i s t u r ec o n t e n t,t e x t u r ec h a r a c t e r i s t i c s,m i c r o s t r u c-t u r e,c r y s t a l l i z a t i o n c h a r a c t e r i s t i c s,t h e r m a l c h a r a c t e r i s t i c s a n ds h o r t-r a n g eo r d e r e ds t r u c t u r e o fL i a n g p iw e r e a n a l y z e d.T h e r e s u l t s s h o w e d t h a t:d u r i n g t h e s t o r a g e p e r i o do f0~7d a y s, t h em o i s t u r e c o n t e n t d e c r e a s e d f r o m33.17%t o28.54%,t h e h a r d n e s s i n c r e a s e d f r o m169.83g t o294.38g,t h e c h e w i n e s s i n c r e a s e d f r o m61.37t o118.51,a n d t h em i c r o s t r u c t u r e c h a n g e df r o ms m o o t hn e t w o r ks t r u c t u r e t or o ug ha n d p o r o u ss t r u c t u r e,r e s u l t i n g i nth e g r a d u a l d e-c l i n e o f t a s t ea n ds e n s o r y s c o r e.T h ede g r e eo fs h o r t-r a n g eo r d e ro fs t a r c hi n c r e a s e df r o m0.51t o1.07,t h e c r y s t a l t y p e c h a n g e d g r a d u a l l y f r o m A-t y p e t oB-t y p e,t h e r e l a t i v e c r y s t a l-l i n i t y i n c r e a s e df r o m2.1%t o16.8%,a n dt h ee n t h a l p y o f r e t r o g r a d a t e ds t a r c hi n c r e a s e df r o m3.02J/g t o3.92J/g.D u r i n g s t o r a g e,th eh e li xs t r u c t u r eo fs t a r c h m o l e c u l e s w a s*收稿日期:2021-07-08基金项目:国家自然科学基金项目(31772012)作者简介:黄峻榕(1971-),女,福建福州人,教授,博士生导师,研究方向:食品大分子资源的开发与利用Copyright©博看网 . All Rights Reserved.陕西科技大学学报第39卷f o r m e db y h y d r o g e n b o n d s,a n dt h ed e g r e eo fs h o r t-r a n g eo r d e ro fs t a r c h m o l e c u l e si n-c r e a s e d.T h eh e l i x s t r u c t u r ew a s r e g u l a r l y s t a c k ed t o f o r mc r y s t a l s,a n d t h en u m be rw a s i n-c r e a s e d.T h e s e r e s u l t sa b o u t s t o r a g e q u a l i t y d e c l i n er u l ea n dc h a n g e m e c h a n i s m o fL i a n g p i p r o v i d e d a t h e o r e t i c a l b a s i sf o r i m p r o v i ng th e q u a li t y s t a b i l i t y o fL i a n g p i a n d i n d u s t r i a l p r o-c e s s i n g.K e y w o r d s:L i a n g p i;r e t r o g r a d a t i o no f s t a r c h;c r y s t a l l i n i t y;o r d e r e d s t r u c t u r e0 引言凉皮起源于陕西省岐山县,被认定为中华名吃之一[1].根据原料和加工工艺的不同,凉皮分为面皮[2]㊁擀面皮[3]和米面皮.凉皮生产除了现制现售外,还有小规模的方便凉皮生产方式.方便凉皮主要分为保鲜凉皮㊁冷冻凉皮㊁干燥凉皮三种[4].淀粉的回生使凉皮食味及其它性能显著变劣,因此分析凉皮中淀粉回生的机理是凉皮工业化及标准化加工生产的重要课题.糊化后的淀粉在低温下自然冷却,淀粉分子趋向于有序排列,这个过程称为淀粉的回生[5-7].近年来国内外学者对淀粉及食品回生特性进行大量研究.卢芸[8]研究表明油糕的回生进程在7d内最快,主要原因是直链淀粉的重结晶.钱平等[9]研究表明馒头中蛋白质含量增多会加速馒头的回生.L i 等[10]研究了淀粉链长分布和米饭短期回生特性之间的因果关系,研究表明支链淀粉和直链淀粉分子都参与了短期回生过程,对米饭的质构特性(硬度和粘性)有显著影响.张雨等[11]研究表明青麦糕中的淀粉重结晶方式为瞬间成核,短时间内回生严重.Z h u[12]研究表明馒头回生与水分迁移有关.G o n g等[13]研究表明大米淀粉的回生涉及直链淀粉和长支链淀粉内部链之间的相互作用.卜宇[14]研究表明燕麦面条回生时间长于48h时,面条蒸煮损失随着老化时间的继续增加而升高,而回生值㊁相对结晶度随着老化时间的增加而降低.总之,目前国内外关于食品及淀粉回生的研究主要集中在淀粉链长分布㊁直链淀粉与支链淀粉比例㊁蛋白㊁水分等各种因素对淀粉回生特性影响的研究,国内外有关传统食品凉皮回生行为的研究尚未见报道.凉皮的回生缩短其货架期,因此明晰凉皮的回生规律及机理,对延长凉皮货架期,促进其工业化发展具有重要的指导意义.基于此,本研究的目的是系统研究凉皮在贮藏期间回生行为并分析其品质变化的原因,为凉皮的工业化及加工生产提供理论依据,从而提高凉皮经济效益,拓展凉皮产品的市场空间.1 材料与方法1.1 材料与仪器1.1.1 主要材料与试剂小麦淀粉,上海正宝惠食品有限公司;无水乙醇(色谱纯),天津市天力化学试剂有限公司;溴化钾(色谱纯),天津市科密欧化学试剂有限公司.1.1.2 主要仪器T A.X TP l u sC物性分析仪,美国S M S公司; Q2000型示差扫描量热分析仪,美国T A公司;D8 A d v a n c e X-射线衍射仪,德国布鲁克公司; S T A449F3傅里叶红外光谱仪,德国布鲁克公司; Q45型扫描电镜,美国F E I公司;1.2 实验方法1.2.1 凉皮样品制备选取小麦淀粉进行凉皮制作.淀粉与水比例为1∶2,调制成淀粉乳.凉皮罗底部刷上少量食用油,倒入适量的淀粉乳使其均匀分散在罗底,加热熟制3m i n之后放入凉水中冷却至室温,凉皮表面刷油防止粘连.将成品凉皮进行真空包装,将包装好的凉皮置于4℃温度下分别存放0d㊁1d㊁3d㊁5d㊁7 d,以0d作为对照组.利用水分活度仪测定凉皮水分含量.1.2.2 质构特性的测定采用T A.X TP l u sC物性分析仪进行测定.将样品置于物性分析仪中进行测试,选择二次压缩(T P A)模式和A/L K B型探头.参数设置:测试速度都设定为1.00mm/s;样品压缩程度为75%;两次压缩之间停留时间为5 s,触发力5g;压缩次数2次,每项测试重复3次.1.2.3 热学特性测定利用Q2000型差式扫描量热仪(美国T A公司)测定凉皮热学参数.分别取储存不同时间凉皮样品冻干粉于铝盘中,加入蒸馏水配成质量分数为30%的悬浮液,压盘密封.利用Q2000型差式扫描量热仪测定.测试参数:升温速率为10℃/m i n,升温范围为20℃~100℃.测试结束得到起始温度(T o)㊁峰值温度(T p)㊁终止温度(T c)及焓值(ΔH)等热学参数.㊃04㊃Copyright©博看网 . All Rights Reserved.第6期黄峻榕等:凉皮(面皮)贮藏过程中的回生行为及其机理1.2.4 结晶特性测定将贮存不同时间(0d㊁1d㊁3d㊁5d和7d)的凉皮冻干粉采用D8A d v a n c eX-射线衍射仪进行表征,测定参数设置:波长1.542Å,管压40k V,管流40m A,扫描速度4°/m i n,2毴变化范围4°~ 40°,D S:1°,S S:1°,R S为0.3mm.相对结晶度利用分析软件J a d e6.0计算.1.2.5 扫描电子显微镜观察采用Q45扫描电子显微镜(美国F E I公司)对凉皮截面的微观结构进行观察.在扫描电镜(S E M)的专用的载物台上粘贴双面导电胶,冻干后的样品经预处理后固定于导电胶上,样品截面朝上.经过真空喷金处理后,将载物台放入样品室进行观察并拍照.操作过程中的模式为高真空二次电子成像,电压设置为15k V.1.2.6 短程有序结构测定采用溴化钾(K B r)压片法,按照淀粉样品1%比例与K B r充分混合㊁研磨㊁压片进行测试.测试条件为:扫描波数设置为全波长4000~400c m-1 (4000~1300c m-1为官能团区,1300~800c m-1为指纹区),分辨率为4c m-1,使用OMN I C软件对样品图谱进行去卷积处理.1.2.7 凉皮感官评价根据相关文献中的感官评价标准,制定出凉皮感官评价标准,对凉皮色泽(10分),口感(20分)㊁表观(10分)㊁粘性(25分)㊁韧性(25分)㊁光滑性(5分)㊁味道(5分)进行评分.1.2.8 统计学分析使用O r i g i n2018软件进行绘图,运用S P S S 22.0软件进行数据分析.2 结果与讨论2.1 凉皮贮藏过程中水分含量的变化图1是贮藏不同天数凉皮的水分含量图.由图1可知,新鲜凉皮的水分含量约为33.17%,随着贮存时间的延长,凉皮水分含量逐渐减少,由0d的33.17%逐渐减少到3d的29.99%.5d水分含量为28.87%,7d水分含量为28.54%,5d至7d水分含量的变化趋势比较平缓,这是因为真空包装在一定程度上减少了凉皮水分的散失[15].凉皮是水分含量较高的食品,水分含量的高低能够很大程度地说明凉皮的新鲜程度.水分含量影响食品的口感及食用品质,水分含量的减少和重新分布均会导致食品质构特性的变化.含淀粉较多的食品中水分含量会影响淀粉回生的速度,当淀粉类食物中的水分含量在30%~60%之间时,食物中的淀粉最容易发生回生[16].图1 贮藏不同天数凉皮的水分含量2.2 凉皮贮藏过程中质构性质的变化经过真空包装的凉皮在4℃条件下贮存0d㊁1 d㊁3d㊁5d㊁7d后进行全质构测定,其质构参数变化结果如表1所示.由表1可知,随着凉皮贮存时间的延长,凉皮的硬度变化整体上呈现出持续性增大的趋势.硬度是测定淀粉回生的一个典型的宏观特性,是一个与淀粉回生直接相关的因素[17].0d 凉皮的硬度是169.83g,在3d时硬度迅速增大至243.79g,在贮存至第7d时,凉皮的硬度增大到294.38g.咀嚼性是食物被咀嚼到可以直接吞下时所需的能量[18],凉皮的咀嚼性从61.37逐渐增大至118.51.凉皮在贮藏过程中硬度和咀嚼性明显增加,是由于凉皮中的淀粉发生回生.随着淀粉分子重新有序排列,淀粉链之间相互作用增强,食品体系的坚实性和强度增加,表现为硬度㊁咀嚼性显著增大[19].感官评价数据表明,随着凉皮贮藏天数增加,评分逐渐降低说明其品质逐渐变劣.表1 贮藏不同天数凉皮质构特性的变化贮藏时间/d硬度/g粘性弹性内聚性胶粘性咀嚼性回复性感官评分0169.83±22.19c-1.69±0.57a0.90±0.09a0.57±0.11a111.99±28.72a61.37±23.44b0.33±0.08a90.99±1.29a 1176.64±18.61c-2.91±2.48a0.72±0.05c0.55±0.02a84.90±16.72b99.97±14.50a0.29±0.04a88.08±1.96a b 3243.79±41.47b-1.74±1.27a0.83±0.12a b0.49±0.05b121.38±18.61a103.07±22.90a0.23±0.06b85.35±2.16b 5258.65±76.65a b-2.21±0.70a0.74±0.09b c0.21±0.10c47.35±14.02c112.86±9.90a0.15±0.04c82.79±2.48c 7294.38±39.02a-1.07±0.54a0.78±0.11b c0.43±0.06b125.68±12.57a118.51±21.20a0.23±0.03b76.54±2.68d㊃14㊃Copyright©博看网 . All Rights Reserved.陕西科技大学学报第39卷2.3 凉皮贮藏过程中微观形貌的变化对贮藏不同天数凉皮的形貌进行观察,如图2所示.0d的凉皮表面光滑,具有良好的色泽与透明度(如图2(a)所示).当凉皮放置1d后,表面的光泽度降低(如图2(d)所示);贮藏时间增加至3d 后,由于凉皮的硬度增大导致凉皮折叠处断裂,这与质构参数中的硬度参数变化一致(如图2(g)㊁2 (j)㊁2(m)所示).使用扫描电镜对凉皮的微观形貌进行观察.凉皮在制作过程中小麦淀粉经过糊化后形成网络状的凝胶结构.0d的凉皮内部分布大小不一的孔洞,内部呈光滑的网络状结构且连接紧密(如图2(b)㊁2(c)所示),网孔结构是由于冷冻干燥时脱水而形成的;当贮存天数为1d时,部分孔隙边缘出现塌陷(如图2(e)所示),部分网络状结构断裂(如图2(f)所示),这是因为在贮藏期间伴随着水分的丢失及淀粉回生,网络状结构失水塌陷.贮藏3d之后,孔隙边缘出现大范围断裂的情况(如图2(h)所示),导致内部结构出现大范围的塌陷(如图2(i)所示).放置5d后的样品内部出现大范围的塌陷,孔洞变得粗糙㊁不均匀,内部网状结构连接处变窄,且出现刺突状的断裂点(如图2(k)㊁2 (l)所示).7d后的样品内部表面粗糙,结构疏松多孔,网络状连接减弱,出现大范围的断裂,说明其品质已出现劣变.(a)㊁(b)㊁(c)贮藏0d(d)㊁(e)㊁(f)贮藏1d(g)㊁(h)㊁(i)贮藏3d(j)㊁(k)㊁(l)贮藏5d(m)㊁(n)㊁(o)贮藏7d图2 贮藏不同天数凉皮的扫描电镜图像2.4 凉皮贮藏过程中热学性质的变化使用D S C对凉皮的淀粉热学特性进行测定,得到其D S C曲线如图3所示,热力学参数值如表2所示.从表2所示实验结果可以看出,随着贮藏时间的延长,融化淀粉结晶的起始温度(T o)从0d的42.86℃升高到47.14℃.峰值温度(T p)从49.99℃增大至51.74℃.终止温度(T c)从53.28℃增加至58.96℃.热焓值表示的是融化淀粉重结晶所需的能量,凉皮的热焓值(ΔH)从3.02J/g增加至3.92J/g,热力学参数都增大,表明凉皮重结晶不断增加,回生程度增加.淀粉回生形成的有序晶体结构重新熔融需外加能量,D S C分析图谱中吸热峰面积所表示的淀粉晶体融化的热焓焓变(ΔH),与淀粉回生程度成正相关.随贮藏天数的增加,凉皮吸热峰逐渐增大,表明凉皮回生程度增大.这是因为在贮藏过程中,淀粉分子逐步趋向于低能态有序化结构,淀粉分子间形成氢键而发生聚集重排,形成结晶聚合物[20].图3 贮藏不同天数凉皮D S C曲线表2 贮藏不同天数凉皮的热力学参数贮藏时间/d起始温度T0/℃峰值温度T p/℃终止温度T c/℃热焓值ΔH/(J/g) 042.86±0.27e49.99±0.11c53.28±0.34d3.02±0.46b 144.51±0.22d50.31±0.06b c55.61±0.25c3.37±0.28a b 345.83±0.26c50.85±0.42b56.48±0.34b c3.46±0.27a b 546.33±0.69b50.91±0.84b56.92±0.23b3.60±0.48a 747.14±0.42a51.74±0.58a58.96±0.84a3.92±0.72a ㊃24㊃Copyright©博看网 . All Rights Reserved.第6期黄峻榕等:凉皮(面皮)贮藏过程中的回生行为及其机理2.5 凉皮贮藏过程中晶体结构变化X R D 用于分析淀粉样品的无定形/结晶状态[21].A -型特征峰出现在2θ为15°㊁17°㊁18°和23°,一般认为是谷物淀粉晶型[22].原小麦淀粉为典型的A -型结晶.小麦淀粉和凉皮中的淀粉X -射线衍射图和相应的结晶度如图4所示.由图4可知,在17°和20°处有两个主要的宽峰.凉皮中淀粉的重结晶类型为B -型,B -型结晶的特征是在2θ角为17°处有一个明显的峰,该峰的形成与支链淀粉在回生过程中有序重结晶有关[23].淀粉的晶型从A 型向B 型的转变表明天然小麦淀粉的结晶结构在糊化和回生过程中被破坏.出现晶型变化的原因是淀粉在糊化时颗粒破裂重组,直链淀粉的双螺旋结构被破坏,原小麦淀粉结晶结构被破坏.随着凉皮的回生,直链淀粉及支链淀粉的排列趋于有序化,体系内分子聚集形态发生变化.凉皮中的淀粉结晶化程度不断增加,逐步变成一种更稳定的B -型结晶模式[24].(a )小麦淀粉X -射线衍射图(b )凉皮淀粉X -射线衍射图图4 小麦淀粉、凉皮淀粉的X -射线衍射图淀粉的回生不仅涉及部分支链淀粉的变化,还与直链淀粉的变化有关.直链淀粉能够与淀粉颗粒中的脂肪酸和磷脂形成复合物,产生V -型结晶,其在2θ为20°处有明显的特征峰[25].图4中20°出现峰是因为储存期间形成的V -型结晶直链淀粉-脂质复合物的存在.根据X -射线衍射图谱计算相对结晶度,0d 样品的相对结晶度为2.1%,随着贮藏天数的增加,相对结晶度在7d 增加至16.8%.相对结晶度增大的同时,淀粉在2θ为17°㊁20°处的衍射峰变得更尖锐,表明晶体的形成增加,淀粉的有序程度增加[26].2.6 贮藏不同天数对凉皮短程有序结构的影响淀粉颗粒分为结晶区和无定形区.由直链淀粉和支链淀粉的短链形成的双螺旋结构称为淀粉的短程有序结构.在淀粉颗粒内这些双螺旋链通过分子间相互作用,形成长程有序结构,即晶体[27].淀粉红外光谱图中1047c m -1处吸收峰与淀粉的结晶区有关,1022c m -1处的吸收峰与淀粉无定形区有关,995c m -1处的吸收峰则对应羟基的弯曲振动[28,29].凉皮样品在400~4000c m -1范围内的红外光谱图如图5所示.由图5可知,样品在3600~3000c m -1㊁2950~2850c m -1㊁1630c m -1㊁800~1300c m -1处出现峰,分别对应于H 键㊁C-H 拉伸㊁淀粉中的结晶水和淀粉区域[30].通常将1047c m -1与1022c m -1处的吸光度之比,1022c m -1和995c m -1的吸光度之比表征淀粉的短程有序度[27].凉皮样品红外光谱去卷积之后的比值结果如表3所示.由表3可知,随着贮藏天数的增加,凉皮中淀粉1047/1022c m -1从0.51升高至1.07,1022/995c m -1从1.16降低至0.91,表明淀粉的短程有序度增大.图5 贮藏不同天数凉皮淀粉红外光谱图表3 储藏不同天数凉皮淀粉的短程有序参数贮藏时间/d1047/1022/c m -11022/995/c m -100.511.1610.701.0130.710.9550.940.9471.070.91㊃34㊃Copyright©博看网 . All Rights Reserved.陕西科技大学学报第39卷3 结论本研究对凉皮在贮藏期间回生行为引起的品质变化及潜在的机理进行分析,结果表明凉皮的水分含量从33.17%降低至28.54%,质构参数表明硬度从169.83g增大到294.38g,咀嚼性从61.37增加至118.51.由于水分散失和淀粉回生造成凉皮微观结构由光滑的网络状结构变为粗糙㊁疏松多孔结构,这是导致凉皮口感变差㊁感官评分下降的主要原因.热力学参数都增大表明淀粉重结晶不断增加;淀粉的晶型从A-型转变为B-型,且相对结晶度从2.1%增加至16.8%,凉皮的短程有序度从0.51增大至1.07.在贮藏过程中,淀粉分子从无序结构重新形成螺旋结构,使得淀粉的短程有序度增加.螺旋结构规则排列形成结晶,且相对结晶度不断增大,分子的空间排列发生变化,使得凉皮的持水力下降,硬度增大,网络结构塌陷断裂.也就是说,凉皮品质下降的机理为淀粉分子短程有序结构和相对结晶度的逐渐增加造成的回生.凉皮回生阻碍了其工业化生产的发展,给生产和消费带来极大的损失,通过研究凉皮在贮藏期间的品质劣变的机理,为进一步改良凉皮品质和延长货架期提供参考价值及依据.参考文献[1]孙川惠,武 强,张炳文.淀粉凝胶食品 粉皮㊁凉粉的研究进展[J].中国食物与营养,2016,22(1):40-43.[2]张 雷,张建新,李赛杰,等.传统蒸面皮抗老化配方优化研究[J].农产品加工,2016(6):28-32.[3]冉 娇.传统擀面皮工艺条件优化及品质变化探讨[D].杨凌:西北农林科技大学,2016.[4]林致通.凉皮食用品质标准建立和方便凉皮生产技术研究[D].重庆:西南大学,2020.[5]W a n i AA,S i n g hP,S h a hM A,e t a l.R i c e s t a r c h d i v e r s i t y:E f f e c t so ns t r u c t u r a l,m o r p h o l o g i c a l,t h e r m a l,a n d p h y s i-c o c h e m i c a l p r o p e r t i e s:A r e v i e w[J].C o m p r e h e n s i v e R e-v i e w s i nF o o dS c i e n c e&F o o dS a f e t y,2012,11(5):417-436.[6]M a t i g n o n A,T e c a n t e A.S t a r c h r e t r o g r a d a t i o n:F r o ms t a r c h c o m p o n e n t st oc e r e a l p r o d u c t s[J].F o o d H y d r o-c o l l o id s,2016,68(7):43-52.[7]W a n g S J,L i CL,C o p e l a n dL,e t a l.S t a r c h r e t r o g r a d a t i o n:Ac o m p r e h e n s i v er e v i e w[J].C o m p r e h e n s i v e R e v i e w si nF o o dS c i e n c e&F o o dS a f e t y,2015,14(5):568-585.[8]卢 芸.扬州千层油糕老化特性研究及营养卫生学评价[D].扬州:扬州大学,2020.[9]钱 平,李里特,何锦风.馒头硬化机理探讨[J].中国食品学报,2005,5(4):79-86.[10]L i C,L u oJX,Z h a n g C Q,e t a l.C a u s a l r e l a t i o n sa m o n g s t a r c hc h a i n-l e n g t hd i s t r i b u t i o n s,s h o r t-t e r mr e t r o g r a d a-t i o na n dc o o k e dr i c et e x t u r e[J].F o o d H y d r o c o l l o i d s, 2020,108(6):106064.[11]张 雨,张 昀,崔亚鹏,等.青麦糕的抗老化工艺研究[J].河南工业大学学报(自然科学版),2021,42(2):36-42.[12]Z h uF.S t a l i n g o fC h i n e s es t e a m e db r e a d:Q u a n t i f i c a t i o na n d c o n t r o l[J].T r e n d s i nF o o dS c i e n c e&T e c h n o l o g y, 2016,55:118-127.[13]G o n g B,C h e n g LL,G i l b e r tR,e t a l.D i s t r i b u t i o n o f s h o r t t o m e d i u m a m y l o s ec h a i n sa r e m a j o rc o n t r o l l e r so fi n v i t r o d i g e s t i o n o f r e t r o g r a d e d r i c e s t a r c h[J].F o o dH y d r o c o l l o i d s,2019,96:634-643.[14]卜 宇.淀粉老化调控对燕麦全粉挤压面条蒸煮品质的影响[D].西安:陕西师范大学,2018.[15]L i uY,W a n g XL,L iXP,e t a l.C h i n e s e s t e a m e db r e a d:P a c k a g i n g c o n d i t i o n s a n d s t a r c h r e t r o g r a d a t i o n[J].C e r e-a l C h e m i s t r y,2019,96(1):95-103.[16]白亚丁.高水分米糕的抗老化研究[D].无锡:江南大学, 2009.[17]O hS M,C h o iH D,C h o iH W,e t a l.S t a r c hr e t r o g r a d a-t i o n i nr i c e c a k e:I n f l u e n c e s o f s u c r o s e s t e a r a t e a n d g l y c-e r o l.[J].F o o d s(B a s e l,S w i t z e r l a n d),2020,9(12):17-37.[18]W a n g SN,K h a m c h a n x a n aP,Z h uF,e t a l.T e x t u r a l a n d s e n s o r y a t t r i b u t e so f s t e a m e db r e a df o r t i f i e d w i t hh i g h-a m y l o s e m a i z es t a r c h[J].J o u r n a lo fT e x t u r eS t u d i e s, 2017,48(1):3-8.[19]周 颖.不同种类糯米糕老化特性研究[D].无锡:江南大学,2013.[20]张晓宇,张丹丹,李荣芳,等.皂荚糖胶对玉米淀粉老化性质影响及体系的水分分布[J].食品科学,2021,42(12): 31-36.[21]Q i uS,Y a d a vM P,Z h uQ M,e t a l.T h ea d d i t i o no f c o r nf i b e rg u mi m p r o v e s th e l o n g-t e r ms t a bi l i t y a n d r e t r o g r a-d a t i o n p r o pe r t i e s of c o r n s t a r c h[J].J o u r n a l o f C e r e a l S c i-e n c e,2017,76:92-98.[22]W a n J,Z h o uG H,L u oS J,e t a l.As t u d y o f t h e e f f e c t o fa m i n oa c i d s o n p a s t i n g a n d s h o r t-t e r m r e t r o g r a d a t i o n p r o p e r t i e so fr i c es t a r c hb a s e do n m o l ec u l a rd y n a m i c s s i m u l a t i o n[J].S t a r c hS tär k e,2017,69(9-10):1600238.[23]L i uR,X uC,C o n g X,e t a l.E f f e c t s o f o l i g o m e r i c p r o c y a-n i d i n so nt h er e t r o g r a d a t i o n p r o p e r t i e so f m a i z es t a r c h w i t h d i f f e r e n t a m y l o s e/a m y l o p e c t i n r a t i o s[J].F o o dC h e m i s t r y,2017,221:2010-2017.[24]盛夏璐.常温保鲜馒头淀粉老化研究[D].西安:陕西师范大学,2016.[25]Y a n g X,F e n g M Q,S u n J,e t a l.T h e i n f l u e n c e o f f l a x s e e dg u mo nt h er e t r o g r a d a t i o no fm a i z es t a r c h[J].I n t e r n a-t i o n a l J o u r n a lo fF o o dS c i e n c e&T e c h n o l o g y,2017,52(12):2654-2660.(下转第50页)㊃44㊃Copyright©博看网 . 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Journal of Materials Science and Engineering A 4 (1) (2014) 45-50Effect of Addition of Cashew Nut Shell in Boiler Fuel on the Formation of Slagging and FoulingJohannes LeonardDepartment of Mechanical Engineering, Faculty of Engineering, University of Hasanuddin Jalan Perintis Kemerdekaan Km.10, Makassar 90225, IndonesiaReceived: December 10, 2013 / Accepted: January 03, 2014 / Published: January 10, 2014.Abstract: The cashew nut shell is added to lignite coal with sulfur content above 1.8% against the effects of slagging and fouling on fire tube boiler at PT. Indoofood CBP Tbk Makassar Branch. Testing is done with a variety of fuel usage and condition of fire tube boiler that is 60% lignite coal blending with 40% of cashew nut shell seeds on the condition of fire tube boiler before cleaning, lignite coal under conditions of fire tube boiler before cleaning and lignite coal at conditions fire tube boiler after cleaning. From the experimental condition, it appears that using a fuel mixture of 60% coal lignite and 40% shells of cashew has been approached with the standard conditions of the combustion temperature is 1,543 °C. As for the burning exit temperature is approaching the requirements, that is equal to 838 °C. Similarly, the exit gas temperature before the fire tube boiler cleaned lower than the temperature of the gas exit pipe fire when only using lignite coal fuel. The results showed that by using lignite coal with a sulfur content above 1.8% resulted slagging index of 1.42 but when using a mixture of 60% lignite coal sulfur content above 1.8% and 40% cashew nut shell produced slagging index 0.86. As for the fouling index Na2O is 0.34% to 0.05%. It was concluded that 60% of the fuel mix of coal and lignite 40% cashew nut shell can reduce the formation of slagging and fouling.Key words: Lignite coal, cashew nut shell, fire tube boiler, slagging, fouling.1. IntroductionIn the combustion zone with high temperature, oxidation and reduction will occur. The content of minerals in the ash react with each other and react with organic and inorganic content of the coal and the combustion gases such as SO2 results. The compounds formed by the interaction of materials that causes problems of deposits. Slagging is the phenomenon of molten ash particles stick it on the wall of the combustion chamber due of decomposition of alkali compounds (ash content) contained in coal combustion chamber at temperatures higher than the melting temperature of the ash . Meanwhile, fouling is a phenomenon of stick and fly ash buildup (fly ash) carried on the gases of combustion at the fire in theCorresponding author: Johannes Leonard, associate professor, research field: corrosion. E-mail: ***************************.pipeline due to a decrease in temperature.One of the problems in the use of lignite coal with high sulfur levels that exceed the standard required of the type of boiler used in PT. Indoofood CBP Sukses Makmur Tbk, Makassar Branch is a maximum of 1.8%. High level of sulfur can cause slagging and fouling in the combustion chamber at the fire tube boiler which can inhibit heat transfer process [1]. This research wants to analyze the use of lignite coal, and lignite coal 60% mixed with 40% of cashew nut shell to the effects of slagging and fouling on that fire tube boiler. Through this research , the industry can figure out how big the fire tube boiler performance to be applied in order to maximize its use.2. Experimental Methods and Facilities UsedThe experimental study was conducted with thevariation of fuel usage and condition of fire tube boilerAll Rights Reserved.Effect of Addition of Cashew Nut Shell in Boiler Fuel on the Formation of Slagging and Fouling 46that is 60% lignite coal blending with 40% of cashew nut shell on the condition of fire tube boiler before cleaning, lignite coal under conditions of fire tube boiler before cleaning and lignite coal on the condition of fire tube boiler after cleaning . In the third condition the analysis of data taken aproximat, fire exit temperature pipe.Fuel used by the boiler is lignite coal from the District Mallawa of Bone in South Sulawesi, while the shell of the cashew come from Bone Southern Sulawesi [2]. Before being used in the burning process in this boiler, coal is tested its composition first in Sucofindo, Makassar. The classification of this coal is lignite coal as a low content of Fixed carbon 37.1 wt%, and Calorific Value Up ( Gross Calorific Value) is up to 6.239 kcal/kg .This research was conducted at the Department of Engineering utility PT. Indofood CBP Tbk Makassar Branch. This type of research is an experimental study of the variation of fuel.2. Materials and MethodsData processing was to analyze the potential for slagging and fouling on fire tube boiler when using lignite coal fuel and 60% when using a mixture of coal and lignite 40% cashew nut shell. Ash particles on coal is a source of sediment deposits on the surface of walls or parts of boiler that detains heat transfer process in the boiler. The precipitate that formed from the ashes can be divided into two forms, namely the slagging and fouling. Potential slagging and fouling potential, then determined based on each index. These indices compared to the fuel before and after mixing cashew nut shells.3. Results and DiscusionClassification of coal ash used is bituminous coal ash as:Fe2O3 > CaO + MgO24.50% > 3.48% + 1.32%24.50% > 4.80%Data analysis of ash shell cashew and lignite ash as: Fe2O3 < CaO + MgO3.99% < 25.64% + 1.88%3.99% < 27.54%Slagging and fouling index calculation using ash content and proximate analysis of fuel. Then the index value obtained of slagging and fouling on each fire tube boiler conditions. One way to predict the slagging potential is based on the calculation of basic and acid ratio in percent by weight dry basis of sulfur in coal as the following way:B = CaO + MgO + Fe2O3 + Na2O + K2O= 3.48 + 1.32 + 24.50 + 0.34 + 1.10= 30.74A = SiO2 + Al2O3 + TiO2= 41.07 + 25.27 +0.97= 67.31S = Dry weight percentage of sulfur in the coal base = 3.10So slagging index values obtained for lignite ash:SABRs⨯⎪⎭⎫⎝⎛=s30.74R 3.10% 1.42%67.31⎛⎫=⨯=⎪⎝⎭Because the Rs value obtained was in the range 0.6 < Rs < 2.0 then the potential for slagging when using coal fuel is being categorized as medium.To determine the potential formation of slagging when using a fuel mixture of 60% coal and 40% cashew nut shell beans, then the calculation of the composition according to the percentage of ash fuel consumption.Following the calculation of the index slagging in fire tube boiler when using a mixture of 60% fuel and 40% coal cashew seed shells:B = (60% CaO coal+ 40% CaO shells of cashew) + (60% MgO coal+ 40% MgO shells of cashew) + (60% Fe2O3 coal + 40% Fe2O3 shells of cashew) + (60% Na2O coal + 40% Na2O shells of cashew) + (60% K2O coal + 40% K2O shells of cashew)= (60% ⨯ 3.48 + 40% ⨯ 25.64) + (60% ⨯ 1.32+ 40%All Rights Reserved.Effect of Addition of Cashew Nut Shell in Boiler Fuel on the Formation of Slagging and Fouling47⨯ 1.88) + (60% ⨯ 24.50 + 40% ⨯ 3.9) + (60% ⨯ 0.34 +40% ⨯ 0.65) + (60% ⨯ 1.10+ 40% ⨯ 0)= 31.27 A = (60% SiO 2 coal + 40% SiO 2 shells of cashew) + (60% Al 2O 3 coal + 40% Al 2O 3 shells of cashew) + (60% TiO 2 coal + 40% TiO 2 shells of cashew) = (60% ⨯ 41.07 + 40% ⨯ 61.83) + (60% ⨯ 25.27 + 40%⨯ 1.99) + (60% ⨯ 0.97 + 40% ⨯ 4.02)= 67.52 S = (60% Dry weight percentage of sulfur in the coal base + 40% weight percentage of sulfur on dry basis cashew shell)= ( 60% ⨯ 3.10 + 40% ⨯ 0) = 1.86So slagging index values obtained for lignite ash:s B R S A =⨯⎛⎫⎪⎝⎭s 31.27R 1.86%0.86%67.52=⨯=⎛⎫ ⎪⎝⎭Because the Rs value obtained was in the range 0.6<Rs <2.0 then slagging potential for fuel use 60% coaland 40% cashew nut shell beans are being categorized as medium.One way to predict the fouling potential is based on the content of Sodium/Sodium in fuel ash as the following way:CaO + MgO + Fe 2O 3 < 20% 3.48% + 1.32% + 24.50% < 20%29.30% > 20%If CaO + MgO + Fe 2O 3 > 20%, then to Na 2O = 0.34%, it’s mean Na 2O < 3, so the potential for foulingwhen using coal fuel categorized as low-medium.To determine the potential for the formation offouling when using a fuel mixture of 60% coal and40% cashew nut shell, then the calculation of thecomposition according to the percentage of ash fuelconsumption. Following the calculation of the index fouling in fire tube boiler fuel mixture when using 60% coal and 40% cashew nut shell.Fouling index when fuel consumption 60% coal and 40% cashew nut shell beans:CaO + MgO + Fe 2O 3 > 20% (60% CaO coal+ 40% CaO shell of cashew) + (60% MgO coal + 40% MgO shell of cashew) + (60% Fe 2O 3 coal + 40% Fe 2O 3 shell of cashew) > 20% (60% ⨯ 3.48 + 40% ⨯ 25.64) + (60% ⨯ 1.32+ 40% ⨯ 1.88) + (60% ⨯ 24.50 + 40% ⨯ 3.9) > 20%30.15 > 20% Na 2O = (60% Na 2O coal + 40% Na 2O shells of cashew seeds) = (60% ⨯ 0.34 + 40% ⨯ 0.65)= 0.05If CaO + MgO + Fe 2O 3 > 20%, then for Na 2O = 0,05% it’s mean Na 2O < 3, so the potential for fouling fuel mixture of 60% coal and 40% cashew nut shell categorized as low-medium.Fig. 1 shows that the slagging condition before cleaning, burning temperature in the burning chamber when using a mixture of 60% lignite coal and 40% is higher than the burning temperature when only using lignite coal fuel. The burning temperature when using a fuel mixture of 60% coal lignite and 40% cashew nut shell, temperature is 1,543 °C. When using lignite coal before cleaning is 1,427 °C, and when using lignite coal after cleaning is 1,360 °C. This happens because the shells of cashew has a value of volatiles composition of matter/substance fly higher than lignite coal (volatiles matter cashew nut shell 68.03%, lignite coal 42.10%) [3].Fig. 1 Graph showing the relationship between boiler fueland temperature gases out of the combustion chamber andthe burning temperature. 0500100015002000Coal + cashew shell beforecleaning Coal before cleaning Coal after cleaning Tgas out (°C)Tburning (°C)All Rights Reserved.Effect of Addition of Cashew Nut Shell in Boiler Fuel on the Formation of Slagging and Fouling 48The cashew shell possess ash content lower than the lignite coal (ash content of cashew nut shell beans and 2, and ash content of lignite coal 10.90%) although the calorific value of lignite coal is higher than the shells of cashew (HHV lignite coal ranges from 26,121 kJ/kg and 26,026 kJ/kg, while HHV shells of cashew 9,101 Btu/lb). Volatile matter flame propagation towards the coal, where a mixture of volatile matter and combustion air and gas will raise turbulence towards of the coal That will be burned and increasing effect of burning temperature. The high ash content values inhibit burning air to burn carbon so not all of the carbon could be converted into CO2. It reduced the value of heat of burning, and resulting lower burning temperature value [4].Burning exit temperature of the gas mixture when using of 60% lignite coal and 40% cashew nut shell before cleaning is lower than the burning temperature of the fuel when just use lignite coal before cleaning (burning exit gas temperature when using a fuel mixture of 60% coal lignite and 40% cashew nut shell before cleaning temperature of 838 °C and burning when using lignite coal before cleaning is 875 °C and when using lignite coal after cleaning is 846 °C). This occurs because the index of slagging on boiler when using lignite coal fuel has a value higher than when the boiler slagging index using a mixture of 60% fuel and 40% lignite coal cashew nut shel (slagging index when using coal fuel 1.42%, and slagging index when using a mixture of 60% coal and 40% of cashew nut shells before the cleaning 0.86%). Because the index slagging on boiler when using coal fuel is higher, then the radiation heat transfer from the burning chamber is not so much to flow to the side so that the water temperature is still high enough out of the burning chamber. On the condition of the boiler after cleaning, slagging index has no significant influence, but its value is still higher than when using fuel mixtured of 60% coal and 40% cashew nut shell.The temperature of the gas exit of pipe fire is showed by the presence of fouling in pipes. The relation of boiler to temperature conditions gas fire exit pipe is shown in Fig. 2, it shows that the temperature of the gas exit pipe fire when using a mixture of 60% and 40% lignite coal cashew nut shell before cleaning is lower than the temperature of the gas exit pipe fire when only using lignite coal fuel (gas exit temperature of the fire pipeline when using a fuel mixture of 60% lignite coal and 40% cashew shell before cleaning temperature is 208 °C, and burning when using lignite coal before cleaning is 270 °C, and when using lignite coal after cleaning is 171 °C). This occured because the index fouling on boiler when using lignite coal fuel is higher than value of slagging index when boiler using a mixture of 60% fuel and 40% lignite coal cashew shell (index fouling when using coal fuel Na2O is 0.34% and fouling index when using a mix of 60% coal and 40% cashew nut shell Na2O is 0.05%). It appears that using a fuel mixture of 60% coal and 40% lignite shells of cashew has been approached with the given standard conditions of the boiler maker (ALSTOM), where the required burning temperature is 1,600 °C while burning temperature of lignite coal mixture 60% and 40% cashew nut shell is 1,543 °C. The burning exit temperature required is 800 °C [5, 6], while the burning temperature of the mixture lignite coal 60% and 40% cashew nut shell is 838 °C.The effect of slagging and fouling index influenced T burning, T gas out,T gas out pipe, boiler efficiency,and steamFig. 2 Relationship between boiler fuel and temperature exit of the gas pipeline fire.12501300135014001450150015501600Coal +cashew shellbeforecleaningCoal beforecleaningCoal aftercleaningTgas out pipe(°C)All Rights Reserved.Effect of Addition of Cashew Nut Shell in Boiler Fuel on the Formation of Slagging and Fouling 49flow rate.The condition of the boiler before and aftercleaning using some conditions of coal fuel, shown inFigs. 3-5.(a)(b)Fig. 3 Condition of the boiler using a fuel mixture of 60% lignite coal and 40% cashew nut shell beans before cleaning: (a) slagging and (b) fouling.(a)(b)Fig. 4 Condition of the boiler using lignite coal fuel before cleaning: (a) slagging and (b) fouling.(a)(b)Fig. 5 Condition of boiler using lignite coal fuel after cleaning: (a) slagging and (b) fouling.Furthermore, Fig. 5 shows the condition of boiler using lignite coal fuel after cleaning.4. ConclusionsBy using lignite coal with a sulfur content above 1.8% resulting slagging index of 1.42, but when using a mixture of 60% lignite coal with a sulfur content above 1.8% and 40% cashew nut shell produced slagging index of 0.86. By using lignite coal with a sulfur content above 1.8% resulted fouling index Na2O is equal to 0.34% however, when using a mixture of 60% lignite coal sulfur content above 1.8% and 40% cashew nut shell produced fouling index Na2O is 0.05%.AcknowledgmentsThanks to Novarini, our graduate student, who has contributed in the retrieval of this research data.References[1]H.E. Belkin, S.J. Tewalt, Geochemistry of Selected CoalSamples from Sumatera, Kalimantan, Sulawesi andPapua, Indonesia, Balcanica, Science for a ChargingWord, 2010, p. 6. All Rights Reserved.Effect of Addition of Cashew Nut Shell in Boiler Fuel on the Formation of Slagging and Fouling 50[2]I. Gondosari, Y. Rumawan, Training Coal Boiler. Jakarta.HO Manufacturing PT. Indoofood Sukses Makmur, 2009.[3]Risfahri, Cardanol From Seed Nut Oil Skin With VacuumDistillation Method, Balai Besar Penelitian dan Pengembangan Pascapanen Pertanian Institut PertanianBogor, 2004.[4]J.R.S, Ahamed, H.H. Masjuki, Energy, Exergy andEconomic Analysis of Industrial Boilers, Ph.D. Thesis,Department of Mechanical Engineering, University ofMalaya, Kuala Lumpur Malaysia, 2010.[5]V.G. Nierop, Thompson Afripac Coal Fired BoilerOperating & Maintenance Manual, Alstom John Thompson (Pty) Limited, South Africa, 2002.[6]J.B. Kitto, C. Stevan, S. Steam, The Babcock andWilcox Company Barbeton, Ohio USA, 2005, pp. 279,463-475.All Rights Reserved.。