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机械毕业设计英文外文翻译62超薄HfO2薄膜纳米划痕测试的力学性能研究

机械毕业设计英文外文翻译62超薄HfO2薄膜纳米划痕测试的力学性能研究
机械毕业设计英文外文翻译62超薄HfO2薄膜纳米划痕测试的力学性能研究

附录:译文

超薄HfO2薄膜纳米划痕测试的力学性能研究

摘要:

测试10nm的原子沉积HfO2薄膜的耐磨性和压痕硬度,从而研究退火对其力学性能影响。超薄片在低负荷时的耐磨损性能是通过原子力显微镜的纳米划痕试验测量。纳米划痕的深度随退火温度升高而降低,这表明退火后薄膜的硬度随退火温度的升高而增加。通过纳米划痕试验产生表面压痕。退火后的薄膜硬度变化的主要原因是由于退火产生了HfSixOy。 X-射线光电子能谱(XPS)测量证明,HfSixOy的硬度随退火温度的升高而增加。存在的HfSixOy扩大了界面,使界面层的厚度的增加。因此,表面硬度随退火产生的HfSixOy的增加而增加。

关键词: HfO2;薄膜;纳米压痕;原子力显微镜;纳米压痕。

1、介绍

在半导体产业中,为了以较低的成本获得良好的功能和性能,晶体管的沟道长度和栅介电层厚度等特征尺寸被要求不断缩小[1-3]。二氧化铪(HfO2)由于其具有相对较高的介电常数,折射率大,并且具有宽的带隙,是一种很有前途的材料,以取代二氧化硅[2-4]用于减少栅极绝缘层的厚度。但是,氧化铪在硅片上不具有热稳定性。

HfO2薄膜的热退火引起的结构和界面的稳定性的变化已经得到了广泛的研究。X射线衍射分析(XRD)表明,如相,结晶和晶粒度大小等结构性能由退火温度决定[5,6]。现通过光谱椭偏观察到的光学常数随退火温度的增加而增加[6,7]。电子电路应用程序的集成兼容性和长期可靠性取决于其机械性能,这是由于其耐磨损性,热循环和内应力依赖于它们。然而,由于热退火引起的力学性能变化并不完全取决于HfO2薄膜,特别是几纳米厚度的变化。

在这篇文章中,10纳米厚的氧化铪薄膜的机械性能取决于耐磨性和压痕硬度。热退火的耐磨性和压痕硬度的变化分别从纳米划痕测试和表面纳米压痕获得。划痕的深度用原子力显微镜(AFM)测量,其被用作评价薄膜的耐磨性和硬度的指标[8-10]。通过表面纳米压痕确认纳米划痕测试的结果。此外,热退火引起结构特征的改变是通过X射线光电子能谱(XPS)来确定它们的原因。

2、实验

2.1样品制备和特征

在以前的研究中,10 nm厚的HfO2薄膜是用原子层沉积(ALD)方法沉积在8英寸(20.32厘米)(100)p-型硅晶片上[11]。由于在进行ALD沉积之前没有清洗,二氧化铪(HfO2)层和Si基片层之间将会形成的氧化物(SiO2)。底层的SiO2层对HfO2薄膜的热稳定性没有明显的影响[12]。在Ar

保护下,退火炉温度为450℃?750℃,在退火炉中退火10分钟。

通过透射型电子显微镜(FE-TEM,JEM-2100号,日本电子,美国)对膜的厚度,原沉积和退火HfO2薄膜的横截面进行了评价。高亮度肖特基场发射电子枪产生的FE-TEM的探针的小于0.2 nm。超高点至点FE-TEM分辨率为0.19纳米。通过双束聚焦离子束(DB-FIB)技术获得高200千伏分辨率的FE-TEM图像。最初的氧化铪薄膜样品切成1.0厘米的区域。通过DB-FIB进行10 pA至5 nA的抛光,直到通过FE-TEM测量样品的厚度达到大约为100 nm。

采用XPS(VG ESCA,Scientific Theta Probe,UK)技术确定HfO2薄膜详细的化学结构的。单色和Al的Kα(1486.6 eV)的X射线源用于探测化学和结构的组合物。该系统配备了的电子分析仪其起飞角为53°。膜表面通过Ar离子在3000 eV和1μA的溅射进行化学元素Si,O,铪,和C的剖析。XPS经过能量为50 eV,步长为0.05 eV进行测量。

2.2机械性能的特征

通过商业AFM(尺寸3100 Nanoman,Veeco公司)的执行环境条件下进行纳米划痕实验。选择金刚石涂层的高耐磨损性的硅探针在HfO2薄膜表面形成反复划痕(纳米传感器DT-NCHR),目的是在划痕之后保持恒定的顶端形状。探头有10微米高的的三角锥型尖端和100纳米的曲率半径尖端,如图1(a)。探针的弹簧常数为42 N / m,谐振频率为330千赫。大约40μN正常力产生3微米长的划痕,z方向如图1(b)所示,划痕速度为1000nm/s。划痕方向如图1(b)的x方向,垂直于所述悬臂长度方向(y方向)。需要注意的是退火后的氧化铪薄膜的晶体结构具有各向异性(X射线衍射获得的数据没有列出来)。因此,划痕的性能是所有方向的总体表现。在这项研究中,划痕的方向是随机选择的。薄膜划痕的探测是通过Ultrasharp硅探针(NSC15/50,硅MDT,俄罗斯有限公司)轻轻敲击,以防止对凹划痕产生额外的损害。硅刻蚀探针的针尖是NSC 15/50的圆锥形状和一个半径为大约10纳米,弹簧常数为45 N / m和谐振频率为350千赫的针尖。划痕的平均深度超过3μm的18横截面划痕(AB,如图1)。

通过动态的的接触系统(纳米压痕G200,安捷伦技术,美国)形成纳米压痕和计算水平接触表面的氧化铪薄膜的硬度[13]。在实验过程中,z轴位移的灵敏度与从负荷-位移曲线的噪声宽度有关系。薄膜表面通过半径约20 nm的Berkovich金刚石的三角锥形尖端产生划痕。通过三角锥形的金刚石尖端确定AFM划痕硬度,并与得到的纳米压痕进行比较。HfO2薄膜测试表面的泊松比为0.35。加载过程中漂移率低于0.05nm/s和恒应变速率约0.005 nm/s。

3.实验结果与讨论

3.1 AFM的纳米划痕深度

沉积和550℃退火后的氧化铪膜的FE-TEM横截面图像如图2,如FE-TEM图像所示为二氧化铪(HfO2)层的沉积样品,主要是嵌入在结构中的非晶态纳米晶体。图2(b)中可以清楚地观察到550℃退火样品结晶铪层。对于如此沉积的样品,氧化铪层的厚度约10.1 nm和界面层的SiO2厚度约0.9 nm。对于550℃退火的样品,二氧化铪(HfO2)层的厚度为约0.9 nm,这可能是由于厚度沉积均匀性不一致和FE-TEM横截面图像边缘测定所造成的。

图3表明了550℃和750℃退火HfO2薄膜的典型沉积和相应的横截面图片的纳米划痕。观察沿突起两侧的划痕。非对称的V形锥体的AFM针尖的横截面轮廓形状如图1(a),由于非对称V形锥体的AFM的针尖划伤薄膜表面,会在凹划痕集中区域产生非对称突起,划痕右侧的突起高度远小于左侧。据此前报道[14-16],在划伤过程中,磨损碎屑沉积物和塑性变形往往积聚在划痕的两侧,在凹划痕周围形成凸部,。此外,由于薄膜划痕硬度降低,划痕深度增加,凸部高度也增加。根据Tseng[10,16,17]和Kassavetis等人[18],通过AFM针尖划伤产生的突起高度可以作为划痕深度。

纳米划痕实验测量的划痕深度用来评价力学性能[10,18,19]。划痕深度定义为划痕底部到未刮开表面的距离,如图3。获得划痕深度为5.46 nm到12.51nm。在沉积膜中,探头正常力为6μN时产生的划痕深度12.51nm。针尖通过氧化铪和SiO2层渗透Si底板。在550℃下,根据FE-TEM横截面图像,划痕深度为8.28nm,这是底部的二氧化铪(HfO2)层到界面附近的距离决定的,如图2。对于750℃的退火薄膜,深度为5.46,大约是到氧化铪层的一半。划痕深度随退火温度的增加而下降,表明退火后薄膜硬度随退火温度的增加而增加。结果表明,氧化铪薄膜的耐磨性随退火温度的增加而增加。

3.2纳米压痕硬度

退火引起的HfO2薄膜硬度变化是由金刚石锥体探针使用连续硬度测量(CSM)的方法[13,20]测量的纳米压痕进行评价。在纳米压痕的过程中,随着压痕载荷的增加驱动压头向样品移动。所施加的压头位移,作为函数连续记录一个完整循环的加载和卸载。沉积和氧化铪薄膜在550℃和750℃下的典型负载循环如图4(a)和基于CSM方法得到的硬度如图4(b)。HfO2薄膜的退火硬度大于原沉积的膜,并随退火温度的增加而增加。这一观察结果证实了纳米划痕实验得到的测量结果。由于硬度随退火温度的增加而增加,退火后的氧化铪薄膜难以划伤,样品在较高的退火温度下得到较低的划痕深度。

简谐接触硬度也可以从加载的压痕试验和确定相同相和相的部分反应结果获得[20-22]。于图部分。如图4(b),根据各个相的反应结果推测压痕深度,谐波接触刚度沿各表面等效压痕深度测量。在第一个大约3nm的压痕中,接触硬度很大程度上受纳米压痕前端与最外层的超薄HfO2薄膜充分接触的影响[22]。因此,根据线性拟合,沿均匀性薄膜的渗透硬度得到的位移的范围为3至10 nm和10为20 nm。这表明,HfO2薄膜的结构在深度方向上有多层或梯度(非均匀)[20]。第一个10nm 区域的曲线特征为谐波与硬度的联系,该区域包括HfO2的层以及薄的SiO2层。在压头到达Si基板的谐波接触的剩余部分硬度可以用一条直线来表示。然而,根据梯度结构膜(后面的XPS分析将会显示)和基板可以看出HfO2,SiO2和Si的测量压痕接口之间没有明确的分离点。

3.3通过XPS分析HfO2薄膜的化学成分

简谐接触硬度表面HfO2薄膜的ALD均匀性随深度变化。要检查退火引起的结构变化,通过X射线光电子能谱深度对HfO2薄膜进行化学分析。

图5表明通过HfO2退火薄膜(750℃)的HF、O和硅元素的浓度评估XPS中Ar离子溅射时间。应当指出的是,溅射过程会产生物理和化学反应,从而改变溅射前HfO2的组成。如先前所报道[23-25],在HfO2薄膜的HF,HfO x,HfO2的混合物内形成高能Ar离子。此外,在high-k薄膜中优先溅射会导致HF,O和硅元素溅射速率的变化[23,26]。例如,已经发现,铪会导致表面分离和屏蔽溅射过程中的硅原子,从而降低溅射率。这可能会大大降低Hfrich薄膜在Si基板上的溅射速率[26]。

high-k薄膜的元素组成也可以受到影响。例如,Hf浓度随着溅射时间增加会导致HfO2层的氧的优先溅射[23]。

从表面的顶部的第一个300秒的溅射时间内,相对应HF和O的原子百分比,在该地区硅是不存在的,如图5。这表明的氧化铪是该层的主要成分。溅射后,在O和HF浓度随溅射时间的增加而减少,而Si浓度增加(在660 s超过70%)。当Ar离子溅射离开这层时,Hf较长的衰减会导致进入基板时的优先溅射[26]。然而,它也表明,Hfsi x o y 结构[5,27-29]形成的溅射时间为300秒。通过在无离子溅射过程中使用的角分辨XPS已观察到Hfsi x o y 的界面结构[29,30]。图5表明HfO2和SiO2层之间广泛的界面层形成具有复杂结构的Hfsi x o y 。[5,7,11,27–29]

因此,组成HfO2薄膜的层状结构[11,29]为HfO2、Hfsi x o y 、SiO2层和从顶部向底部的Si基板。Hfsi x o y 层的厚度随着退火温度的增加而增加,这是因为退火过程中会产生Hf硅酸盐[7,11]。谐波接触刚度型材的层状结构和扩大的Hfsi x o y 层中也观察到纳米压痕测量曲线。

4、结论

在标准厚度为10nm,相应的两个退火温度下,用原子力显微镜(AFM)和垂直敏感纳米压痕分别测试超薄氧化铪薄膜的耐磨损性和压痕硬度。实验结果表明,在退火过程中形成铪结晶相和复杂的Hfsi x o y化合物,这是由于热扩散在界面处形成HfO2/SiO2。因此,HfO2薄膜的纳米压痕硬度随着的Hfsi x o y 层的增加而增加,随着退火温度的增加而增加,这是由于Hfsi x o y的硬度比铪大。因此,退火HfO2薄膜纳米划痕深度随退火温度增加而降低,表面硬度(由AFM测量)和纳米硬度(由纳米压痕测量)随退火温度增加而增加。

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附录:译文原件

桥梁工程毕业设计外文翻译箱梁

桥梁工程毕业设计外文翻译箱梁

西南交通大学本科毕业设计(论文) 外文资料翻译 年级: 学号: 姓名: 专业: 指导老师:

6 月

外文资料原文: 13 Box girders 13.1 General The box girder is the most ?exible bridge deck form. It can cover a range of spans from25 m up to the largest non-suspended concrete decks built, of the order of 300 m. Single box girders may also carry decks up to 30 m wide. For the longer span beams, beyond about 50 m, they are practically the only feasible deck section. For the shorter spans they are in competition with most of the other deck types discussed in this book. The advantages of the box form are principally its high structural ef?ciency (5.4), which minimises the prestress force required to resist a given bending moment, and its great torsional strength with the capacity this gives to re-centre eccentric live loads, minimising the prestress required to carry them.

机械类外文文献

附:外文翻译 外文原文: Fundamentals of Mechanical Design Mechanical design means the design of things and systems of a mechanical nature—machines, products, structures, devices, and instruments. For the most part mechanical design utilizes mathematics, the materials sciences, and the engineering-mechanics sciences. The total design process is of interest to us. How does it begin? Does the engineer simply sit down at his desk with a blank sheet of paper? And, as he jots down some ideas, what happens next? What factors influence or control the decisions which have to be made? Finally, then, how does this design process end? Sometimes, but not always, design begins when an engineer recognizes a need and decides to do something about it. Recognition of the need and phrasing it in so many words often constitute a highly creative act because the need may be only a vague discontent, a feeling of uneasiness, of a sensing that something is not right. The need is usually not evident at all. For example, the need to do something about a food-packaging machine may be indicated by the noise level, by the variations in package weight, and by slight but perceptible variations in the quality of the packaging or wrap. There is a distinct difference between the statement of the need and the identification of the problem. Which follows this statement? The problem is more specific. If the need is for cleaner air, the problem might be that of reducing the dust discharge from power-plant stacks, or reducing the quantity of irritants from automotive exhausts. Definition of the problem must include all the specifications for the thing that is to be designed. The specifications are the input and output quantities, the characteristics of the space the thing must occupy and all the limitations on t hese quantities. We can regard the thing to be designed as something in a black box. In this case we must specify the inputs and outputs of the box together with their characteristics and limitations. The specifications define the cost, the number to be manufactured, the expected life, the range, the operating temperature, and the reliability. There are many implied specifications which result either from the designer's particular environment or from the nature of the problem itself. The manufacturing processes which are available, together with the facilities of a certain plant, constitute restrictions on a designer's freedom, and hence are a part of the implied specifications. A small plant, for instance, may not own cold-working machinery. Knowing this, the designer selects other metal-processing methods which can be performed in the plant. The labor skills available and the competitive situation also constitute implied specifications. After the problem has been defined and a set of written and implied specifications has been obtained, the next step in design is the synthesis of an optimum solution. Now synthesis cannot take place without both analysis and optimization because the system under design must be analyzed to determine whether the performance complies with the specifications. The design is an iterative process in which we proceed through several steps, evaluate the results, and then return to an earlier phase of the procedure. Thus we may synthesize several components of a system, analyze and optimize them, and return to synthesis to see what effect this has on the remaining parts of the system. Both analysis and optimization require that we construct or devise abstract models of the system which will admit some form of mathematical analysis. We call these models

机械毕业设计英文外文翻译460数字控制 (2)

附录 科技译文: Numerical Control Numerical Control(NC) is a method of controlling the movements of machineComponents by directly inserting coded instructions in the form of numerical data(numbers and data ) into the system.The system automatically interprets these data and converts to output signals. These signals ,in turn control various machine components ,such as turning spindles on and off ,changing tools,moving the work piece or the tools along specific paths,and turning cutting fluits on and off. In order to appreciate the importer of numerical control of machines ,let’s briefly review how a process such as machining has been carried out traditionally .After studying the working drawing of a part, the operator sets up the appropriate process parameters(such as cutting speed ,feed,depth of cut,cutting fluid ,and so on),determines the sequence of operations to be performed,clamps the work piece in a workholding device such as chuck or collet ,and proceeds to make the part .Depending on part shape and the dimensional accuracy specified ,this approach usually requires skilled

机械专业毕业论文外文翻译

附录一英文科技文献翻译 英文原文: Experimental investigation of laser surface textured parallel thrust bearings Performance enhancements by laser surface texturing (LST) of parallel-thrust bearings is experimentally investigated. Test results are compared with a theoretical model and good correlation is found over the relevant operating conditions. A compari- son of the performance of unidirectional and bi-directional partial-LST bearings with that of a baseline, untextured bearing is presented showing the bene?ts of LST in terms of increased clearance and reduced friction. KEY WORDS: ?uid ?lm bearings, slider bearings, surface texturing 1. Introduction The classical theory of hydrodynamic lubrication yields linear (Couette) velocity distribution with zero pressure gradients between smooth parallel surfaces under steady-state sliding. This results in an unstable hydrodynamic ?lm that would collapse under any external force acting normal to the surfaces. However, experience shows that stable lubricating ?lms can develop between parallel sliding surfaces, generally because of some mechanism that relaxes one or more of the assumptions of the classical theory. A stable ?uid ?lm with su?cient load-carrying capacity in parallel sliding surfaces can be obtained, for example, with macro or micro surface structure of di?erent types. These include waviness [1] and protruding microasperities [2–4]. A good literature review on the subject can be found in Ref. [5]. More recently, laser surface texturing (LST) [6–8], as well as inlet roughening by longitudinal or transverse grooves [9] were suggested to provide load capacity in parallel sliding. The inlet roughness concept of Tonder [9] is based on ??e?ective clearance‘‘ reduction in the sliding direction and in this respect it is identical to the par- tial-LST concept described in ref. [10] for generating hydrostatic e?ect in high-pressure mechanical seals. Very recently Wang et al. [11] demonstrated experimentally a doubling of the load-carrying capacity for the surface- texture design by reactive ion etching of SiC

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外文出处: 《Exploiting Software How to Break Code》By Greg Hoglund, Gary McGraw Publisher : Addison Wesley Pub Date : February 17, 2004 ISBN : 0-201-78695-8 译文标题: JDBC接口技术 译文: JDBC是一种可用于执行SQL语句的JavaAPI(ApplicationProgrammingInterface应用程序设计接口)。它由一些Java语言编写的类和界面组成。JDBC为数据库应用开发人员、数据库前台工具开发人员提供了一种标准的应用程序设计接口,使开发人员可以用纯Java语言编写完整的数据库应用程序。 一、ODBC到JDBC的发展历程 说到JDBC,很容易让人联想到另一个十分熟悉的字眼“ODBC”。它们之间有没有联系呢?如果有,那么它们之间又是怎样的关系呢? ODBC是OpenDatabaseConnectivity的英文简写。它是一种用来在相关或不相关的数据库管理系统(DBMS)中存取数据的,用C语言实现的,标准应用程序数据接口。通过ODBCAPI,应用程序可以存取保存在多种不同数据库管理系统(DBMS)中的数据,而不论每个DBMS使用了何种数据存储格式和编程接口。 1.ODBC的结构模型 ODBC的结构包括四个主要部分:应用程序接口、驱动器管理器、数据库驱动器和数据源。应用程序接口:屏蔽不同的ODBC数据库驱动器之间函数调用的差别,为用户提供统一的SQL编程接口。 驱动器管理器:为应用程序装载数据库驱动器。 数据库驱动器:实现ODBC的函数调用,提供对特定数据源的SQL请求。如果需要,数据库驱动器将修改应用程序的请求,使得请求符合相关的DBMS所支持的文法。 数据源:由用户想要存取的数据以及与它相关的操作系统、DBMS和用于访问DBMS的网络平台组成。 虽然ODBC驱动器管理器的主要目的是加载数据库驱动器,以便ODBC函数调用,但是数据库驱动器本身也执行ODBC函数调用,并与数据库相互配合。因此当应用系统发出调用与数据源进行连接时,数据库驱动器能管理通信协议。当建立起与数据源的连接时,数据库驱动器便能处理应用系统向DBMS发出的请求,对分析或发自数据源的设计进行必要的翻译,并将结果返回给应用系统。 2.JDBC的诞生 自从Java语言于1995年5月正式公布以来,Java风靡全球。出现大量的用java语言编写的程序,其中也包括数据库应用程序。由于没有一个Java语言的API,编程人员不得不在Java程序中加入C语言的ODBC函数调用。这就使很多Java的优秀特性无法充分发挥,比如平台无关性、面向对象特性等。随着越来越多的编程人员对Java语言的日益喜爱,越来越多的公司在Java程序开发上投入的精力日益增加,对java语言接口的访问数据库的API 的要求越来越强烈。也由于ODBC的有其不足之处,比如它并不容易使用,没有面向对象的特性等等,SUN公司决定开发一Java语言为接口的数据库应用程序开发接口。在JDK1.x 版本中,JDBC只是一个可选部件,到了JDK1.1公布时,SQL类包(也就是JDBCAPI)

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附录A 英文文献 Drive Axle All vehicles have some type of drive axle/differential assembly incorporated into the driveline. Whether it is front, rear or four wheel drive, differentials are necessary for the smooth application of engine power to the road. Powerflow The drive axle must transmit power through a 90°angle. The flow of power in conventional front engine/rear wheel drive vehicles moves from the engine to the drive axle in approximately a straight line. However, at the drive axle, the power must be turned at right angles (from the line of the driveshaft) and directed to the drive wheels. This is accomplished by a pinion drive gear, which turns a circular ring gear. The ring gear is attached to a differential housing, containing a set of smaller gears that are splined to the inner end of each axle shaft. As the housing is rotated, the internal differential gears turn the axle shafts, which are also attached to the drive wheels. Rear-wheel drive Rear-wheel-drive vehicles are mostly trucks, very large sedans and many sports car and coupe models. The typical rear wheel drive vehicle uses a front mounted engine and transmission assemblies with a driveshaft coupling the transmission to the rear drive axle. Drive in through the layout of the bridge, the bridge drive shaft arranged vertically in the same vertical plane, and not the drive axle shaft, respectively, in their own sub-actuator with a direct connection, but the actuator is located at the front or the back of the adjacent shaft

Manufacturing Engineering and Technology(机械类英文文献+翻译)

Manufacturing Engineering and Technology—Machining Serope kalpakjian;Steven R.Schmid 机械工业出版社2004年3月第1版 20.9 MACHINABILITY The machinability of a material usually defined in terms of four factors: 1、Surface finish and integrity of the machined part; 2、Tool life obtained; 3、Force and power requirements; 4、Chip control. Thus, good machinability good surface finish and integrity, long tool life, and low force And power requirements. As for chip control, long and thin (stringy) cured chips, if not broken up, can severely interfere with the cutting operation by becoming entangled in the cutting zone. Because of the complex nature of cutting operations, it is difficult to establish relationships that quantitatively define the machinability of a material. In manufacturing plants, tool life and surface roughness are generally considered to be the most important factors in machinability. Although not used much any more, approximate machinability ratings are available in the example below. 20.9.1 Machinability Of Steels Because steels are among the most important engineering materials (as noted in Chapter 5), their machinability has been studied extensively. The machinability of steels has been mainly improved by adding lead and sulfur to obtain so-called free-machining steels. Resulfurized and Rephosphorized steels. Sulfur in steels forms manganese sulfide inclusions (second-phase particles), which act as stress raisers in the primary shear zone. As a result, the chips produced break up easily and are small; this improves machinability. The size, shape, distribution, and concentration of these inclusions significantly influence machinability. Elements such as tellurium and selenium, which are both chemically similar to sulfur, act as inclusion modifiers in

机械毕业设计英文外文翻译204机电一体化

附录 INTEGRATION OF MACHINERY (From ELECTRICAL AND MACHINERY INDUSTRY)ABSTRACT Machinery was the modern science and technology development inevitable result, this article has summarized the integration of machinery technology basic outline and the development background .Summarized the domestic and foreign integration of machinery technology present situation, has analyzed the integration of machinery technology trend of development. Key word:integration of machinery ,technology,present situation ,product t,echnique of manufacture ,trend of development 0. Introduction modern science and technology unceasing development, impelled different discipline intersecting enormously with the seepage, has caused the project domain technological revolution and the transformation .In mechanical engineering domain, because the microelectronic technology and the computer technology rapid development and forms to the mechanical industry seepage the integration of machinery, caused the mechanical industry the technical structure, the product organization, the function and the constitution, the production method and the management system has had the huge change, caused the industrial production to enter into “the integration of machinery” by “the machinery electrification” for the characteristic development phase. 1. Integration of machinery outline integration of machinery is refers in the organization new owner function, the power function, in the information processing function and the control function introduces the electronic technology, unifies the system the mechanism and the computerization design and the software which constitutes always to call. The integration of machinery development also has become one to have until now own system new discipline, not only develops along with the science and technology, but also entrusts with the new content .But its basic characteristic may summarize is: The integration of machinery is embarks from the system viewpoint, synthesis community technologies and so on utilization mechanical technology, microelectronic technology, automatic control technology,

机械类毕业设计外文翻译

本科毕业论文(设计) 外文翻译 学院:机电工程学院 专业:机械工程及自动化 姓名:高峰 指导教师:李延胜 2011年05 月10日 教育部办公厅 Failure Analysis,Dimensional Determination And

Analysis,Applications Of Cams INTRODUCTION It is absolutely essential that a design engineer know how and why parts fail so that reliable machines that require minimum maintenance can be designed.Sometimes a failure can be serious,such as when a tire blows out on an automobile traveling at high speed.On the other hand,a failure may be no more than a nuisance.An example is the loosening of the radiator hose in an automobile cooling system.The consequence of this latter failure is usually the loss of some radiator coolant,a condition that is readily detected and corrected.The type of load a part absorbs is just as significant as the magnitude.Generally speaking,dynamic loads with direction reversals cause greater difficulty than static loads,and therefore,fatigue strength must be considered.Another concern is whether the material is ductile or brittle.For example,brittle materials are considered to be unacceptable where fatigue is involved. Many people mistakingly interpret the word failure to mean the actual breakage of a part.However,a design engineer must consider a broader understanding of what appreciable deformation occurs.A ductile material,however will deform a large amount prior to rupture.Excessive deformation,without fracture,may cause a machine to fail because the deformed part interferes with a moving second part.Therefore,a part fails(even if it has not physically broken)whenever it no longer fulfills its required function.Sometimes failure may be due to abnormal friction or vibration between two mating parts.Failure also may be due to a phenomenon called creep,which is the plastic flow of a material under load at elevated temperatures.In addition,the actual shape of a part may be responsible for failure.For example,stress concentrations due to sudden changes in contour must be taken into account.Evaluation of stress considerations is especially important when there are dynamic loads with direction reversals and the material is not very ductile. In general,the design engineer must consider all possible modes of failure,which include the following. ——Stress ——Deformation ——Wear ——Corrosion ——Vibration ——Environmental damage ——Loosening of fastening devices

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外文翻译 专业机械设计制造及其自动化学生姓名刘链柱 班级机制111 学号1110101102 指导教师葛友华

外文资料名称: Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处:Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件: 1.外文资料翻译译文 2.外文原文

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Int J Interact Des Manuf(2011)5:103–117 DOI10.1007/s12008-011-0119-7 ORIGINAL PAPER Benchmarking of virtual reality performance in mechanics education Maura Mengoni·Michele Germani· Margherita Peruzzini Received:27April2011/Accepted:29April2011/Published online:27May2011 ?Springer-Verlag2011 Abstract The paper explores the potentialities of virtual reality(VR)to improve the learning process of mechanical product design.It is focused on the definition of a proper experimental VR-based set-up whose performance matches mechanical design learning purposes,such as assemblability and tolerances prescription.The method consists of two main activities:VR technologies benchmarking based on sensory feedback and evaluation of how VR tools impact on learning curves.In order to quantify the performance of the technol-ogy,an experimental protocol is de?ned and an testing plan is set.Evaluation parameters are divided into performance and usability metrics to distinguish between the cognitive and technical aspects of the learning process.The experi-mental VR-based set up is tested on students in mechanical engineering through the application of the protocol. Keywords Mechanical product design·Virtual reality·Experimental protocol·Learning curve· Mechanics education 1Introduction Modern society is dominated by continuous scienti?c and technical developments.Specialization has become one of the most important enablers for industrial improvement.As a result,nowadays education is more and more job-oriented and technical education is assuming greater importance.In this context both university and industry are collaborating to create high professional competencies.The?rst disseminates M.Mengoni(B)·M.Germani·M.Peruzzini Department of Mechanical Engineering, Polytechnic University of Marche, Via Brecce Bianche,60131Ancona,Italy e-mail:m.mengoni@univpm.it knowledge and innovative methods while the second pro-vides a practical background for general principles training. The main problem deals with the effort and time required to improve technical learning,while market competitiveness forces companies to demand young and high-quali?ed engi-neers in short time.Therefore,the entire educational process needs to be fast and ef?cient.Novel information technolo-gies(IT)and emerging virtual reality(VR)systems provide a possible answer to the above-mentioned questions.Some of the most important issues,in mechanical design?eld,are the investigation of such technologies potentialities and the evaluation of achievable bene?ts in terms of product design learning effectiveness and quality.While IT has been deeply explored in distance education,i.e.e-learning,VR still rep-resents a novelty. VR refers to an immersive environment that allows pow-erful visualization and direct manipulation of virtual objects. It is widely used for several engineering applications as it provides novel human computer interfaces to interact with digital mock-ups.The close connection between industry and education represents the starting point of this research. Instead of traditional teaching methods,virtual technolo-gies can simultaneously stimulate the senses of vision by providing stereoscopic imaging views and complex spatial effects,of touch,hearing and motion by respectively adopt-ing haptic,sound and motion devices.These can improve the learning process in respect with traditional teaching meth-ods and tools.The observation of students interpreting two-dimensional drawings highlighted several dif?culties:the impact evaluation of geometric and dimensional tolerances chains,the detection of functional and assembly errors,the recognition of right design solutions and the choice of the proper manufacturing operations.These limitations force tutors to seek for innovative technologies able to improve students’perception.

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