下载文档原格式
UCRL-CONF-230612SALT FOG TEST OF SAM2X5 COATED STAINLESS STEEL CYLINDERL.F.Aprigliano,R.B.Rebak,J-S.Choi,T.Lian, S.D.DayMay1,2007Materials Science and Technology2007Conference,MS&T#07Detroit,MI,United StatesSeptember16,2007through September20,2007DisclaimerThis document was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor the University of California nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or the University of California. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or the University of California, and shall not be used for advertising or product endorsement purposes.SALT FOG TEST OF SAM2X5 COATED STAINLESS STEEL CYLINDERLouis F. ApriglianoStrategic Analysis, Inc.Raul B. RebakJor-Shan ChoiTiangan LianSumner D. DayLawrence Livermore National LaboratoryABSTRACTA salt fog test of an iron-based amorphous metal, SAM2X5, coated Type 316L stainless steel (SS316L) cylinder was made. The cylinder was 30” diameter by 88” long, and 3/8” thick. One end was welded shut with a SS316L end cap before coating. The body of the cylinder and the end cap were both coated. The cylinder was coated with SAM2X5 by the HVOF thermal spray process. The coating thickness was 0.015” to 0.019” thick. The cylinder was tested in a horizontal position. Also included in the test for reference purposes were five coupons (2” x 2” x 1/8”) of uncoated Type 1018 carbon steel (1018CS). The test used an abbreviated form of GM 9540P. Each cycle was 6 hours in duration and the cylinder and reference samples were exposed to a total of eight cycles. The cylinder was in relatively good condition after the test. Along the body of the cylinder only two pinpoint spot sized signs of rust were seen. The 1018CS reference specimens were extensively rusted.INTRODUCTIONIron based amorphous metal coatings have been developed in a program sponsored by the Defense Advanced Projects Agency (DARPA) and the Department of Energy. The program has been managed by the Lawrence Livermore National Laboratory (LLNL). These coatings when fully amorphous have been found to be resistant to salt fog corrosion. If they are partially amorphous they contain alpha ferrite, which is easily corroded in a salt fog environment. One of these coatings, SAM2X5, is being evaluated on large stainless steel cylinders. The quality of the coating is being evaluated by several means, including salt fog testing.EXPERIMENTAL PROCEDUREA SS316L stainless steel cylinder 30” dia. X 88” long, and 3/8” thick has been coated with SAM2X5, an iron based amorphous metal coating. The compositions of SAM2X5 and SS316L alloys are given in Table 1. One end was welded shut with a SS316L end cap before coating. The body of the cylinder and the end cap were both coated. There were no intentionally un-coated areas on the finished cylinder. The high velocity oxy-fuel thermal (HVOF) spray process was used to apply the coating. The coating was applied to a thickness of 0.015 to 0.019” thick. The cylinder was tested in the horizontal position, as shown in Figure 1. Other images of the cylinder in the as-received condition are given in Figures 2. Also included in the test for reference purposes were five coupons (2” x 2” x 1/8”) of uncoated Type 1018 carbon steel. Photographs of the reference specimens in the as-received condition can be seen in Figure 3. The salt fog test used an abbreviated form (Table 3) of the GM 9540P test cycle1 (Table 4). The full GM cycle is 24 hours long. The abbreviated cycle is 6 hours long and has been found to be adequate in revealing any areas of alpha ferrite in the coating. The cylinder and reference samples were exposed to a total of eight cycles.RESULTSPhotographs of the cylinder at the end of the test are shown in Figure 4. The cylinder was in relatively good condition after the test. Along the body of the cylinder only two pinpoint spot sized signs of rust were seen. These can be seen in Figures 4e and 4f. There was also some rust that developed during the test on the end cap that appears to be related to the welds. This can be seen in Figures 4c and 4d. The 1018CS reference specimens were extensively rusted, as expected. Close-up photos of the reference specimens at the end of the test are shown in Figure 5.SUMMARYA large Type 316L stainless steel cylinder has been coated with an iron-based amorphous metal coating – SAM2X5. A salt fog test has been performed to show that the coating has remained predominately amorphous and has displayed good corrosion resistance. REFERENCES1. “Accelerated Corrosion Test”, General Motors Engineering Standard GM9540P, Dec. 1997.This work was performed under the auspices of the U. S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.Table 1 - Alloy and Coating Nominal CompositionsAlloy Designation HPCRMDesignationNominal Compositions in Weight PercentSS316L SS316L C – 0.03, Mn - 2.00, Si – 1.00, Cr – 16.0 to 18.0,Ni -10.0 to 14.0, Mo 2.0 to 3.0, Fe – balanceSAM2X5 SAM2X5 Cr – 18.5, Mn – 2.0, Mo – 14.0, W – 5.8, B – 3.2, C – 1.0,Si – 1.3, Fe – balance1018 Carbon Steel None C – 0.14 to 0.2, Mn - 0.6 to 0.9, P – 0.04 max., S – 0.05 max., Fe - balanceTable 2 - Summary 2” x 2” x 1/8” Reference SamplesCoating: Substrate: Sample Type Sample ID: Uncoated 1018 Carbon Steel Reference sample A25Uncoated 1018 Carbon Steel Reference sample A26Uncoated 1018 Carbon Steel Reference sample A27Uncoated 1018 Carbon Steel Reference sample A28Uncoated 1018 Carbon Steel Reference sample A29Table 3 - Abbreviated GM Salt Fog Test Cycle Cycle Segment Elapsed Time EventSoaking with Salt Solution 2 minutes Soak samples with a salt solutionmist* for 2 minutes at ambienttemperature: 13 – 28o C (55 - 82o F).High Humidity Exposure 4 hours Expose samples to 100% relativehumidity at 49 ±0.5o C (120 ±1o F),including a 55 minute ramp to wetconditionsSample Drying 1 hours and 58 minutes Heat sample to 60 ±0.5o C (140 ±1o F)and reduce humidity to 30% or less.Hold until dry and then reducetemperature to ambient conditions.Repeat Cycle• A distilled water solution of 0.9% sodium chloride, 0.1% calcium chloride, and 0.25% sodium bicarbonate will be used for the salt solution mist.Table 4. 24 Hour Test Cycle for GM9540P1 Accelerated Corrosion Test.calcium chlorid e, and 0.25% sodium bicarbonate.Figure 1 –Side View of Cylinder Before Salt Fog Testing.a. Capped and welded endb. Open Endc. Rust and chip in coating before start of testd. Scuff mark on cylinder surface as-delivered(Photograph courtesy of Robert Bayles) Figure 2. Additional Photographs of Cylinder in As-received Condition.Figure 3. 1018CS Reference Specimens Before Test Exposureb. Close-up of scuff mark (compare to figure2d)c. End capd. Close-up of rust on end cape. Pinpoint rust spot at tip of arrowf. Second pinpoint rust spot at tip of arrowFigure 4. Cylinder After 8 Abbreviated GM cycles.Figure 5. Reference Specimens Used in Cylinder Salt Fog Test After 8 Abbreviated GM Cycles.。
BEAPHONE SUPPLIER APPROVAL GM APPROVALPART NAME 零件名称SECTION-VALIDATION RESULTS APPROVAL APPROVED经核准的： NOT APPROVED未经核准的：VALIDATION PHASE：DATE：ITEM PROC。
PROCEDURE REQMNT REQMT TITLEREQMT VALUECAR RESPON EVALUATION ##TITLE#MODELSIBILITYPHASEQTY TYPESTARTCOMPLQTYTYPESTAGE4铝型材化学成份Si: 0.3-0.6Fe: 0.1-0.3Cu: ≤0.1Mn: ≤0.1Mg: ≤0.35-0.6Cr: ≤0.05Zn: ≤0.15Ti: ≤0.1SGM980依据供应商自检报告PV 1D 05-10-1005-11-251D Prod5铝型材机械性能抗拉强度：Rm≥130MPaSGM980BEA PV 3D 05-10-1005-11-253D Prod8硬度>9 HV SGM980BEA PV 3D 05-10-1005-11-253D ProdN/S2005-7-26铝饰条PART#UPC#REVISION DATE/LEVELMODEL YEARPLATFORMMODEL#SUPPLIER NAMEREPORTING ENGINEER NAME 张丽荣AUTHORS NAME：SECTION-DFMEA APPROVAL DFMEA批准APPROVED： NOT APPROVED：GM VALIDATION ENGINEER SIGNATURE GM 确认 工程师签名： DATE日期：GM VALIDATION ENGINEER SIGNATUREPHONE#010-********REPORT DATE 2005.11.62006GM980N/S北京埃贝斯乐汽车零部件有限公司NOTESSEC IV-ADV REPORTSAMPLE TIMMING SAMPLES TESTED RESULTS 1GM3997(AA6063-T5)被GM3999代替BEAPHONE SUPPLIER APPROVAL GM APPROVALPART NAME 零件名称SECTION-VALIDATION RESULTS APPROVAL APPROVED经核准的： NOT APPROVED未经核准的：VALIDATION PHASE：DATE：ITEM PROC。
非电镀锌涂装应用(Non-Electrolytically Applied Zinc Rich Coating)1. 范围-规范包含非电镀锌涂装防锈之基本要求.同时防锈使用含润滑成份的蜡或PTFE于上涂层做颜色辨识及润滑作用.1.1材质-包含有机或无机锌片涂于张装于有机或无机之上涂层.依GMW3059规范此涂装于工件上不得含有6架铬.GMW3034规范用于测试是否含有6架铬.此涂装不会产生氢气但于前处理(pretreatment)时如做酸性处理时会吸附氢气.非电镀锌涂装有高渗透性能使氢气逸出可解决于做酸性处理时吸附氢气的问题.1.2 交插参考替代之规范GMW GMW3359Delta MotorsGM do BrasilGM HoldenGM NAO GM7114MISUZUITDC GME0255SAAB1.4典型应用-适用于螺丝之内部或外部涂装(尺寸大于或等于M6)及须高防锈与无氢气破坏涂装要求之含铁工件.但下列情况之工件不适用.1.螺丝.螺母＜M62.工件内部有凹陷部位3.抗镁金属表面4.所有尺寸之垫圈5.须电导之工件2 参考2.1 规范DIN946 ISO 11014-1ISO 1463 ISO 9227SAE/USCAR-5 SAE/USCAR-112.2 GMGM7114M GM9071PGM9501P GM9509PGM9540P GME00255GMW3034 GMW30599981228 998409499856703. 要求:3.1.3.1 外观-须一致不得有碰伤.撕裂.气孔.突起等.涂装须良好附着于工件上.除特别指定外颜色须为银色.3.1.3.2 厚度-涂装于螺丝工件不得造成组装困难且厚度须达到防锈要求.3.1.2.1 螺丝涂装最大厚度受其牙部基本尺寸限制(公差雌h 或H).涂装后之工件用适的”GO”检具检验.涂装前牙部可做成undersize/oversize 以符合涂装后的正确尺寸.涂装后须再验是否符合特殊的机械性要求.3.1.2.2 螺丝头部下之涂装尺寸不得超过25μm.供应商应控制涂装尺寸且纪录归档以备查. ISO 1463规范显围观测涂装厚度.注:若工件须做磷酸盐处理建议为最大厚度3μm透明涂装.3.1.4.1 防锈-涂装后工件依NSS规范做144小时盐雾测试不得有超过5%白色锈斑产生.且经480小时曝晒后工件本体不得有红色锈斑.3.1.4.1.1 大量生产时流程SPC须符合相同之盐雾测试规范 .3.1.4.1.2 每一生产线之每一班须依NSS 规范做最少3PCS样品尺寸之盐雾测试.3.1.4.1.3 流程控制及检验均须纪录.3.1.4.1.4 扣件标表面重要部位测试包含但不限制扣件头部.插口凹陷处.螺母外表面.及垫圈.3.1.4.1.5 防高温(Temperature Resistance)-于工件温度150oC 3小时后亦须符合3.1.4.1防锈规范要求.此测试仅用于第一次交样.3.1.4.2 快速生锈测试-此涂装依GM9540P规范曝晒.测试期间B(16循环).曝晒后重要部位不得有红色锈斑产生.此测试仅用于第一次交样.3.1.4.3 阴极防蚀法-此阴极防蚀涂装可依NSS规范测ISO9227.用自工件本体括下一片样本.此样本最大0.5mm宽.经过96th NSS测试后不会有红色锈蚀产生.此测试仅适用于第一次交样.3.1.4.4 防皱褶及龟裂-涂装表面应自然伸展不得有龟裂或破裂产生.3.4.4.5 附着特性-工件之涂装不得有气孔或其他外观改变.依ISO 9227做最少96小时盐雾测试.当依GM9071P做胶带测试.10分钟后自NSS测试移除将不可有划线X位置两边相加超过3mm涂装脱落.且于胶带下不得有涂装脱落.3.1.4.5.1 工件于首次送样须符合附着测试须求.且测试须列入应用者管制纪画.3.1.4.5.2 大量生产之流程SPC须符合附着要求.3.1.4.5.3 大量生产之流程SPC附着特性测试须依NSS测试(3.1.4.13.1.4.6 化学成份预防-工件涂装交样将依下列规范做化学成份测试.A. 挡风玻璃清洁剂-9985670或类似经GM9509P规范认可.B. 布料清洁剂-9981228或类似经GM9509P规范认可.C. 汽油-GM9501P3.1.4.8 Hydrogen Embrittlement:所有须热处理或高冷处理使心部硬度大于HRC32或表面硬度达HRC35依SAE/US CAR-5流程规范经产生氢气流程达到.3.1.4.9 扭力-拉力:M6或大于M6螺丝之扭力及拉力用M10×1.5替代螺丝测试管制.替代螺丝与大量货同时测试.每一生产线之每一班依SAE/USCAR-11须验最少10PCS.除锁螺丝速度为(30±3)RPM. 6sigma 扭力质范围看下表.测试结果纪录留存备查.牙尺寸替螺丝品号测试螺丝品号测试垫圈品号扭力(Nm) 拉力(kN) 磨擦系数M10×1.5 11516105 11516090 11502644 48±8 28.3 0.13±0.03下列叙述请参阅GMW3044规范。
美国FRIEDRICH 空调负责人0595-3661-7060FRIEDRICH 空调EM24N34AFRIEDRICH空调SL36M30-BITEM 26：AIR condition, 型号：SL36M30-B 厂家：FRIEDRICHFRIEDRICH空调制冷剂R410AFRIEDRICH；TOP DRIVE:CANRIG1250AC-681FRIEDRICH 空调KM24L30-AFRIEDRICH SQ08N10SQ10N10FRIEDRICH振动电机F1.2-2-1.1FRIEDRICH空调SH20M30A美国FRIEDRICH空调EM24N34ASH20M30ASL36M30-BKM24L30-A新型号：SH24M20SH15M30ASH20M50ASH24M20AFEATURES•Permanent split capacitor motor•Hermetically sealed refrigeration system•Environmentally sealed on/off switch and gold plated contacts inthermostat for corrosion resistance•Solid-state control relays for compressor and fan operation•Hot gas bypass allows the air conditioner to operate at low ambientconditions without freezing at outdoor temperatures as low as 45?F (7癈)•Hermetically sealed reciprocating compressor is cooled during therefrigeration cycle, which allows the unit to toleratehigher outdoor temperatures up to 130˚F (55癈)•Larger, commercial grade, enclosed fan motor withhermetically sealed overload for arc-free operation.Totally enclosed to assure efficient operation underadverse electrical conditions•Unit utilizes field supplied, direct-wired, 15-amp circuitwith time-delay fuse that will tolerate current surgewithout tripping the breaker•22-gauge, G60 steel air conditioner cabinet is powdercoated for corrosion protection and to withstand years ofhard use•High density EPS foam insulation for thermal resistanceand sound control•Heavy duty hexacomb packaging resists damage during shipment and isenvironmentally friendlyCOILS COATED FOR CORROSION RESISTANCEMODEL SH24M20•ElectroFin 5-stage, immersion ecoat process on 100% of metallicsurfaces on the outdoor coil provides outstanding corrosion resistance protection in coastal or corrosive environments ELECTROFIN BENEFITS:•Excellent adhesion characteristics•Less than 1% thermal degradation•Outstanding chemical resistance 5-stage ecoat•Passed 6048 hrs.ASTM B-117 Salt SprayELETROFIN MEETS THE FOLLOWING:•MIL-C-46168 Chemical Agent Resistance-DS2, HCI Gas•CID A-A-52474A (GSA)•MIL-STD 810F, Method 509.4 (Sand and Dust)•MIL-P-53084 (ME)-TACOM Approval•MIL-DTL-12468 Decontamination Agent (STB)•DPG (Douglas Proving Grounds) Soil & Water Exposure T ests•GM9540P-97 Accelerated Corrosion T est (120 cycles)•ASTM B117-G85 Modified Salt Spray (Fog) T esting-2,000 hours•ASTM B117 Salt Spray (tested by ARL for Lockheed Martin)MODELS SH15M30A, SH20M30A, SH20M50A•Diamonblue™Advanced Corrosion Protection on theoutdoor coil protects the coil against deterioration andextends the life of the unit especially in coastal orcorrosive environments。
户外环境可靠度测试1. 沙尘/雨淋测试(Dust/Rain Test)对于可便携式、户外用以及汽车电子均有防尘与防水测试要求，在国际上不论是IEC、MIL或ETSI以及SAE 均有订出相对应之测试要求。
消费性产品最常引用规范为IEC/EN 60529(Degrees of protection provided by enclosure)，规范中明文规定产品保护等级与试验程序及方法，目前采用的国家也越来越多。
IEC/EN60529防尘分为6个等级(等级0 ~ 等级5)，防水区分为9个等级(等级0 ~ 等级8)在试验应用上通常以IPXX作为等级区分，IP为International Protection 的缩写，国际上均以此做为保护等级辨识，第一个X所代表的意义为防尘等级，第二个X所代表的意义为防水等级。
若产品标示为IP54，则表示产品防尘等极为5，防水等级为6。
防尘等级(e.g. IP5X-防尘等级5)Level 0: 完全无防尘保护Level 1: 可保护避免直径大于50㎜之异物掉入设备内Level 2: 可保护避免直径大于12㎜之异物掉入设备内Level 3: 可保护避免直径大于2.5㎜之异物掉入设备内Level 4: 可保护避免直径大于1㎜之异物掉入设备内Level 5: 有部分防尘作用，但不得因落入之灰尘影响正常功能运作或降低产品安全性Level 6: 完全防尘防水等级(e.g. IPX4-防水等级4)Level 0: 完全防水无保护Level 1: 仿真水气凝结并垂直滴下产品时之保护作用Level 2: 产品与水滴方向为倾斜15度范围内，水滴垂直滴下时保护作用Level 3: 以60度摇摆臂喷洒水的状况下，能够发挥保护作用Level 4: 可在水喷流状况下，发挥保护作用(任意方向)Level 5: 可在灌水状况下，发挥保护作用（任意方向）2.日照測試全球地区年平均空气温度通常介于 0℃ ~ +40℃之间，而在夏天时高温常介于+30℃ ~ +49℃之间，经常出现之平均高温为+43℃, 此为环境温度(空气温度)，但是对于日晒热辐射效应(Radiation Effect)将增加+17℃ ~ +33℃之间，热辐射效应随试件表面颜色与地面热反射条件而有所不同，对于长期使用于户外之产品须慎选产品表面涂装颜色亦可降低辐射热效应。
GM123MGM124M液体处理用钢制汽车管道1 范围这些规范涵盖了二类适用于汽车的钢制管件。
规定了对基础金属、可选用的涂层材料和涂覆管道的要求。
这些要求适用于出自有时是独立设施的管磨机和涂层涂覆生产线的产品。
此管件使用在自定义零件和总成的生产中。
建议对这些零件和总成组件进行腐蚀性能、传导性及连续性、强度、外观和其他独特应用的关键特性上的验证。
1.1GM123M。
规定了双壁构造的管件要求，双壁与接头在还原气氛下进行铜焊，来生产出能满足液压线路要求的管件。
它不能用于燃油管路是因为残余下的铜会促进酸性气体的形成。
见图 1.1.2GM124M。
规定了单壁结构的管件，接头为电阻焊。
推荐用于燃油管路、动力转向管路、变速器油冷却管路、润滑油管路和真空管路等。
见图1。
1.3管件牌号代码。
推荐3.1节中的代码用于图纸和订购单上来命名管件类型、外径、壁厚、生产条件处理和内径涂层。
1.4典型应用。
GM123M主要用于液压制动管路，而GM124M用于燃油管路、动力转向管路、变速器油冷却管路、润滑油管路和真空管路等。
2 参考标准注：除非另行规定，只适用于最新批准的标准。
2.1 外部标准ASTM A254 SAE J463ASTM A875 SAE J526ASTM B117 SAE J527ASTM B750 SAE J533ASTM E8 SAE J1290SAE J4032.2 GM标准GM4298P GM9508PGM4465P GM9509PGM4653M GM9540PGM6277M GMW3001GM9071P GMW3059GM9102P2.3 附加标准可以联系GM动力材料工程部来获得关于GMPT燃油的信息。
·GMPT-6-006 TF2 汽油·GMPT-5-005 Bio-柴油·GMPT-5-001 #2柴油·GMPT-6-019 氧化汽油·GMPT-6-023 E85 低pHe3 要求3.1 一般要求。
Material Specification Finish (Coating)GMW4205Plating Multilayer Coating/Black Type1ScopeThis specification covers requirements for a corro-sion resistant black organic finish over an electrolyti-cally deposited zinc-iron alloy,nickel alloy and/or zinc-nickel alloy substrate.1.1Material Description.This coating system shall be free of chromium.The final product shall con-form to GMW3059requirements.The plating shall be called out on the part drawing per example shown in paragraph 7.1.1.1Material Identification.Not applicable.1.2Cross-Reference of Replaced Specifications.GMW GMW4205Delta Motors GM do Brasil GM Holdens GMNA GM6138M ISUZU ITDC SAAB1.2.1Specifications Qualified to this Material Specification.Not applicable.1.3Symbol.Not applicable.1.4Typical Application.This coating is intended primarily for bulk processed small steel parts such as bolts,screws and nuts used on exterior visible parts.This coating is especially suitable for internal drive (cross recess,6lobed socket etc.)threaded fasteners and self drilling and tapping screws.e of this coating system on threaded surface and/or bearing surface of joints could effect the torque-tension relationship.It is recommended that a torque-tension study of the fastener joint be performed before releasing this finish on any new application.2ReferencesNote:Only the latest approved standards are appli-cable unless otherwise specified.2.1Normative.DIN 946ISO 1463ISO 9227ASTM D523SAE J1960SAE/USCAR-1SAE/USCAR-5SAE/USCAR-7SAE/USCAR-112.2GM.GM4260P GM4265P GM9071P GM9501P GM9540P GMW3001GMW30592.3Additional.None.3Requirements3.1Requirements on Delivery.3.1.1Chemical Requirements.Not applicable.3.1.2Mechanical Requirements.Not applicable.3.1.3Physical Requirements.3.1.3.1Appearance.This finish shall provide uni-form black color on coated parts.The finished part shall have a gloss of 4or higher (20degree gloss me-ter per ASTM D523).Note:Gloss level of the finished parts (when small)shall be measured on standard panel (steel,75x 200mm)processed with the production parts.3.1.3.2This finish shall not fill driver recess or threads nor interfere with normal fastener installation proce-dures.The finish shall withstand normal handling and storage conditions without damage (chipping,flaking or other)and must not stain or transfer to adjacent parts or operators hands.3.1.3.3The total coating system as received shall not adversely affect the drive system:Internal recess di-mensions,hex size,etc.or function of the fastener.©Copyright 2001General Motors Corporation All Rights ReservedOriginating Department:North American Engineering Standards,Records and DocumentationGMW4205GM WORLDWIDE ENGINEERING STANDARDS3.1.3.4Thickness.T ypical zinc-iron,nickel or zinc-nickel alloy layer shall be(5...20)µm and topcoat layer shall be25µm max.with a total thickness≤45µm.3.1.3.4.1Thickness shall be determined by micro-scope examination of cross sections taken perpendic-ular to significant surfaces.See GM4260P,Recom-mended Practices for Measuring Thickness of Plated Deposits and Anodic Coatings(See GM4260P).3.1.3.4.2In case of bolts and screws,plating thick-ness shall be determined at top of head at midpoint of largest continuous surface.In case of nuts,deter-mine at midpoint of flats(wrenching facets).3.1.3.4.3The maximum thickness of coating which may be applied to threads on threaded products is limited by the basic thread size(tolerance h or H). After coating,parts must gage with appropriate ba-sic size G0thread gage.Threads may be produced undersize/oversize(before coating)to accommodate the coating thickness,providing the finished product (after coating)meets all specified mechanical prop-erties.Where mechanical properties are not speci-fied,undersizing/oversizing is subject to approval by pertinent engineer,and all undersize/oversize shall be within permissible limits as agreed upon.3.1.3.5Adhesion.Parts coated to this specifica-tion shall show no evidence of blistering or other ap-pearance changes after exposure to humidity test-ing per GM4465P for≥96h.When tape tested per GM9071P,10min after removal from humidity there shall be≤3.0mm total peel back(peel back adding both sides of scribed line)from the lines scribed in an ’X’and no other peeling in the area under the tape. This is not applicable to threaded fasteners.Note:This test is applicable for initial approval,appli-cator approval and PP AP submission parts.3.1.3.6Weathering Characteristics.Parts coated to this specification shall show no blistering,peeling, cracking,loss of adhesion,discoloration,or red rust after1316.7kJ/m2in xenon arc per SAE J1960. After weathering test finished parts shall have a gloss level of3or higher(20degree gloss meter,per ASTM D523).Note:The weathering test shall be required to run for initial approval only.3.1.3.7Corrosion Resistance.Significant surfaces of parts exposed to neutral salt spray per ISO9227 shall show no white corrosion after48h exposure,≤10%white corrosion products after144h,and no base metal corrosion after480h exposure.For this test externally threaded fasteners shall be power driven into a tapped hole or nut or steel panel,simu-lating production usage,removed,then installed fin-ger tight or with a hand driver with proper drive bit into acrylic plastic or other inert panel,and exposed in salt spray at(15...30) from the vertical to allow wetting per SAE/USCAR-1.Fasteners shall not drip on other fas-teners during the test.3.1.3.7.1Normal production,processes that are in statistical process control shall yield parts that are ca-pable of meeting the salt spray requirements.3.1.3.7.2A periodic NSS test of the parts being pro-cessed on each line running this coating shall be con-ducted with sample size of3pieces minimum per line per shift.3.1.3.7.3Actual processing control checks to be made and recorded shall be based on chemical manufacturer’s instruction.3.1.3.7.4Parts must be NSS tested to meet the corro-sion resistance requirements on significant surfaces for initial approval of the finish,applicators and PPAP submissions.NSS test need not be completed prior to shipment of parts.3.1.3.7.5Significant surfaces for test evaluation in-clude but are not limited to fastener head,socket re-cess,sems washer and external nut surface.Sharp edges are excluded.3.1.3.7.6Significant surfaces on parts other than threaded fasteners shall be all surfaces excluding sharp edges.3.1.3.8Accelerated Corrosion Test.Accelerated corrosion test shall be conducted with this finish coated parts,11516629or similar cross recessed head screws using production methods(sample size, N=10minimum).The test screws shall be power driven and seated with production type tooling into 60/60galvanized steel test panels that have been painted with standard GM pretreatment,primer,and white base coat/clear coat.The test screws shall be installed in a horizontal row seated25mm min.apart.The screw shall be tested for40cycles per GM9540P,Accelerated Corrosion Test.After24test cycles,the screw heads shall exhibit no red rust and30%max.white corrosion coverage. After40test cycles,the screw heads shall exhibit 10%max.red rust coverage and50%max.white corrosion coverage.Note that all visible surfaces of the seated screw heads including screw heads edges shall be included in the percent of corrosion coverage.©Copyright2001General Motors Corporation All Rights ReservedGM WORLDWIDE ENGINEERING STANDARDS GMW4205Note:This test is required for the initial approval of the finish only.3.1.3.9Temperature Resistance.After heating the parts for1h at+150 C(part temperature)the cor-rosion resistance requirements as specified in para-graph3.1.3.7shall still be met.This test requirement is only for initial approval of the finish material.3.1.3.10Gasoline Resistance.For initial approval of new materials,coated parts shall be soaked for (200±2)s in gasoline as described in GM9501P. After removal of the parts,they shall be allowed to air dry before visual examination.There shall be no color change,wrinkling,or any other change in the coating appearance.3.1.3.11Relief of Hydrogen Embrittlement.All parts heat treated or highly cold worked to a spec-ified core hardness HRC32or greater or surface hardness HRC35or greater,that are processed through a hydrogen generating process,shall be processed by the finish applicator per SAE/USCAR-5and tested for de-embrittlement per SAE/USCAR-7. The sample size for the SAE/USCAR-7test shall be per ASTM F1470.3.1.3.11.1When supplementary treatment is speci-fied for a part that requires baking after plating,the supplementary treatment shall be applied after the baking operation.3.1.3.11.2Hardened parts which have been tem-pered at<+175 C shall be heated to+150 C and held8h,or longer,if necessary.3.1.3.12Torque-Tension Test.Metric threaded fas-teners M6and larger shall be subject to torque-ten-sion monitoring through the use of surrogate M10x1.5 test bolts.T en surrogate bolts shall be processed with the production parts.A minimum of10bolts per finish line per shift shall be monitored per SAE/USCAR-11, except tightening speed shall be(30±3)min-1(RPM). The six(6)sigma torque range values shall be within the listed range(see T able1).The test results shall be maintained on file to be submitted when required.Table1:Torque Range ValuesThread Size Surrogate BoltPart NumberTest NutPart NumberTest WasherPart NumberTorque in NmSAE/USCAR11Tensionin kNM10x1.511516105115160901150264448±828.3Note:Engineering drawings for surrogate fasteners for T orque-tension test are available from Global En-gineering Documents/IHS.3.1.3.13Coefficient of Friction.The coefficient of friction of threaded fasteners shall be0.13±0.03(six sigma values)when tested per DIN946with the fol-lowing exceptions:•Tightening speed shall be(30±3)min-1(RPM)•Test samples(excluding driven fasteners)shall be thoroughly cleaned with an appropriate fluid/chem-ical to remove any grease/oil/wax/other contami-nants.•Test clamping force shall be calculated as75%of proof load.Note:Both,T orque-Tension and Coefficient of Fric-tion tests are required only for the initial approval of the finish material.Suppliers/Applicators can run ei-ther T orque-T ension Test or Coefficient of Friction T est for quality control.3.1.4Additional Requirements.Not applicable.3.2Processing Requirements.Subparagraphs were not applicable.3.3Performance Requirements.Subparagraphs were not applicable.3.4Requirements on other Stages during Life Cy-cle.3.4.1Chemical Requirements.3.4.1.1Recyclability.Parts with this coating shall not have any negative effect on recyclability of the parts.3.4.1.2Physiological Safety.The coating material must not cause any health hazard either to line oper-ators or customers.3.4.2Mechanical Requirements.Not applicable. 3.4.3Physical Requirements.Not applicable.3.4.4Additional Requirements.Not applicable.4Manufacturing ProcessNot applicable.5Rules and Regulations5.1All materials supplied to this specification must comply with the requirements of GMW3001,Rules and Regulations for Material Specifications.©Copyright2001General Motors Corporation All Rights ReservedGMW4205GM WORLDWIDE ENGINEERING STANDARDS5.2All materials supplied to this specification must comply with the requirements of GMW3059,Re-stricted and Reportable Substances for Parts.6Approved SourcesSuppliers to this specification must be approved by the Specialist Team/TDGs.GMNA approved suppli-ers names are available on the on-line MA TSPC Sys-tem.For other GM locations the responsible engineering group should be contacted to obtain the approved sources in the individual countries.7Coding SystemThis material specification shall be referenced in other documents,drawings,VTS,CTS,etc.as follows:“GMW4205”WhereGMW=GM Worldwide4205=Specification number8Release and Revisions8.1Release.This material specification was first ap-proved in AUG2001and published in OCT2001. 8.2Revisions.Not applicable.©Copyright2001General Motors Corporation All Rights Reserved。
