篇一：机械设计制造及其自动化英文
英文原文:
Mechanical properties of materials
The material properties can be classified into three major headings: (1) physical,
(2) chemical, (3) mechanical
Physical properties
Density or specific gravity, moisture content, etc., can be classified under this category.
Chemical properties
Many chemical properties come under this category. These include acidity or alkalinity, react6ivity and corrosion. The most important of these is corrosion which can be explained in layman’s terms as the resistance of the material to decay while in continuous use in a particular atmosphere.
Mechanical properties
Mechanical properties include in the strength properties like tensile, compression, shear, torsion, impact, fatigue and creep. The tensile strength of a material is obtained by dividing the maximum load, which the specimen bears by the area of cross-section of the specimen.
This is a curve plotted between the stress along theThis is a curve plotted between the stress along the Y-axis(ordinate) and the strain along the X-axis (abscissa) in a tensile test. A material tends to change or changes its dimensions when it is loaded, depending upon the magnitude of the load. When the load is removed it can be seen that the deformation disappears. For many materials this occurs op to a certain value of the stress called the elastic limit Ap. This is depicted by the straight line relationship and a small deviation thereafter, in the stress-strain curve (fig.3.1)
. Within the elastic range, the limiting value of the stress up to which the stress and strain are proportional, is called the limit of proportionality Ap. In this region, the metal obeys hookes’s law, which states that the stress is proportional to strain in the
elastic range of loading, (the material completely regains its original dimensions after the load is removed). In the actual plotting of the curve, the proportionality limit is obtained at a slightly lower value of the load than the
elastic limit. This may be attributed to the time-lagin the regaining of the original dimensions of the material. This effect is very frequently noticed in some non-ferrous metals.
Which iron and nickel exhibit clear ranges of elasticity, copper, zinc, tin, are found to be imperfectly elastic even at relatively low values low values of stresses. Actually the elastic limit is distinguishable from the proportionality limit more clearly depending upon the sensitivity of the measuring instrument.When the load is increased beyond the elastic limit, plastic deformation starts. Simultaneously the specimen gets work-hardened. A point is reached when the deformation starts to occur more rapidly than the increasing load. This point is called they yield point Q. the metal which was resisting the load till then, starts to deform somewhat rapidly, i. e., yield. The yield stress is called yield limit Ay.
The elongation of the specimen continues from Q to S and then to T. The stress-strain relation in this plastic flow period is indicated by the portion QRST of the curve. At the specimen breaks, and this load is called the breaking load. The value of the maximum load S divided by the original cross-sectional area of
the specimen is referred to as the ultimate tensile strength of the metal or simply the tensile strength Au.
Logically speaking, once the elastic limit is exceeded, the metal should start to yield, and finally break, without any increase in the value of stress. But the curve records an increased stress even after the elastic limit is exceeded. Two reasons can be given for this behavior:
①The strain hardening of the material;
②The diminishing cross-sectional area of the specimen, suffered on account of the plastic deformation.
The more plastic deformation the metal undergoes, the harder it becomes, due to work-hardening. The more the metal gets elongated the more its diameter (and hence, cross-sectional area) is decreased. This continues until the point S is reached.
After S, the rate at which the reduction in area takes place, exceeds the rate at which the stress increases. Strain becomes so high that the reduction in area begins to produce a localized effect at some point. This is called necking.
Reduction in cross-sectional area takes place very rapidly; so rapidly that the load value actually drops. This is indicated by ST. failure occurs at this point T.Then percentage elongation A and reduction in reduction in area W indicate the ductility or plasticity of the material:
A=(L-L0)/L0*100%
W=(A0-A)/A0*100%
Where L0 and L are the original and the final length of the specimen; A0 and
A are the original and the final cross-section area.
The Two Types Of Power Transmission
In hydraulic power transmission the apparatus (pump) used for conversion of the mechanical (or electrical,thermal) energy to hydraulic energy is arranged on the input of the kinematic chain ,and the apparatus (motor) used for conversion of the hydraulic energy to mechanical energy is arranged on the output (fig.2-1)
The theoretical design of the energy converters depends on the component of the
bernouilli equation to be used for hydraulic power transmission.
In systerms where, mainly, hydrostatic pressure is utilized, displacement (hydrostatic) pumps and motors are used, while in those where the hydrodynamic pressure is utilized is utilized gor power transmission hydrodynamic energy converters (e.g. centrifugal pumps) are used.
The specific characteristic of the energy converters is the weight required for transmission of unit power. It can be demonstrated that the use of hydrostatic energy converters for the low and medium powers, and of hydrodynamic energy converters of high power are more favorite (fig.2-2). This is the main reason why hydrostatic energy converters are used in industrial apparatus. transformation of the energy in hydraulic transmission.
1.
2.
3.
4.
5.
6.
7. driving motor (electric, diesel engine); mechanical energy; pump; hydraulic energy;hydraulic motor; mechanical energy; load variation of the mass per unit power in hydrostatic and hydrodynamic energy converters
1、hydrostatic; 2.hydrodynamic
Only displacement energy converters are dealt with in the following. The elements performing converters provide one or several size. Expansion of the working chambers in a pump is produced by the external energy admitted, and in the motor by the hydraulic energy. Inflow of the fluid occurs during expansion of the working chamber, while the outflow (displacement) is realized during contraction. Such devices are usually called displacement energy converters.
The Hydrostatic Power
In order to have a fluid of volume V1 flowing in a vessel at pressure work spent on compression W1 and transfer of the process, let us imagine a piston mechanism (fig.2-3(a)) which may be connected with the aid of valves Z0 and Z1 to the external
medium under pressure P0 and reservoir of pressure p1.in the upper position of the piston (x=x0) with Z0 open the cylinder chamber is filled with fluid of volume V0 and pressure P0. now shut the value Z0 and start the piston moving downwards. If Z1 is shut the fluid volume in position X=X1 of the piston decreases from V0 to V1, while the pressure rises to P1. the external work required for actuation of the piston (assuming isothermal change) is
W1=-∫0x0(P-P0)Adx=-∫v1v0(P-P0)dv
篇二：机械设计制造及其自动化专业类的简历--英文
西安科技大学机械工程学院2012届应届毕业生
Personal resume
篇三：大学毕业简历 机械设计制造及其自动化 各课程英文翻译
姓 名:
学 历: 大学本科 专 业: 机械设计制造及其自动化 电 话：
XXX
武汉理工大学余家头校区Y499信箱（邮编430063）
Tel： XXXXXXXXXX
Email：
基本信息
籍贯：XXXXXXXXX 性别：男 民族：汉
出生日期：XXXXXX 身高:177cm体重:70kg
政治面貌：中共党员 健康状况:好
教育背景 2006.09——2010.06 院校：武汉理工大学学位：学士学位
专业：机械设计制造及其自动化（港口起重机方向）
主修课程：工程图学、工程材料、理论力学、材料力学、结构力学、机械
原理、机械设计、互换性与测量技术、金属工艺学、机械制造
工艺学、起重运输机械、起重运输机金属结构、现代测试技术、
液压及气压传动、电工电子技术、控制工程基础、机电传动控
制、单片机及接口技术、港口装卸工艺。
辅修课程：工程内燃机、机械振动、最优化技术、技术经济学、数控技术、
设备综合管理、集装箱装卸机械、装卸搬运车辆、可靠性技术、
机械故障诊断、摩擦与润滑。
个人技能
英语技能： 通过国家英语六（561）。
计算机技能：通过计算机二级（C语言），三级（网络技术）。
能熟练使用Word、Excel、Powerpoint办公软件。
熟练掌握AutoCAD机械制图。
初步掌握Solidworks三维建模。
自我评价
充满热情：态度决定一切，对机械行业的热情，让我能全心投入工作
吃苦耐劳：农村的成长环境赐予我的财富。
创新精神：思维活跃，观察细致，创新精神是机械行业的基本素质。
团队精神：较好的适应新环境的能力、随和的性格、开朗的心态、使我能
够很好地融入团队。
兴趣爱好
手工制作：喜欢做一些小手工，勤劳积极，动手能力较好
田径： 良好的身体素质能使我更好的投入到学习和工作中
登山旅行：和旅伴一起感受自然气息，陶冶情操，调节生活
获奖情况
2008/2009年: 两次获得校三等奖学金,院三好学生称号
2008年： 湖北省大学生艺术节合唱一等奖
2008年： 武汉理工大学党校优秀学员
2009年:运动会男子800米冠军/200米亚军
课程设计：2010年6月： 机电传动控制（PLC）课程设计（15天）。
2009年12月：机械设计课程设计（三周）。
2009年6月： 机械原理课程设计（两周）。
实习经历：2010年9月： 生产实习（三周，武船武重中铁等企业）
2009年7月： 暑期强化训练（AutoCAD机械制图训练）
2009年3月: 电工实习（两周，收音机焊接组装）
2008年9月： 金工实习（一个月，车铣锻铸焊数控等）
附言
没有最好只有更好，不断学习，不停进步！
XXXXXX
Tel： XXXXX
Email：XXXXX
Birth Place：XXXXXXXXSex：Male Nation：Han
Date of Birth：XXXXXHight:177cm Weight:70kg
Wuhan University of Technology
Major： Mechanical design and manufacturing
Main courses: Engineering Materials、Theoretical Mechanics、
Mechanics of Materials、Structure Mechanics、
Mechanical Theory、Mechanical Design、
Interchangeability and Measurement Technology、
Modern Testing Technology、Internal combustion engine、
Device Management、Machinery fault diagnosis、
Friction and Lubrication
English skills： Passed CET6 (score 471)
PC Abilities ： Passed NCRE2(C language)，NCRE3(Internet Technology)。
Skilled in use of office & AutoCAD
Enthusiastic：My enthusiasm in cars and machines pour my heart into my job
Hardworking：A big gift from my rural growing environment。
Creative：Active, Meticulous. Creative is one of the most important spirits
Teamwork： I can easily integrate into a community because of my good
adaptability, responsibility and cheerful personality
Handmade 、Track and field、Football 、Read、 Cycling、 Surf the
Internet
Scholarship:
Third school scholarships (2008)
Third school scholarships (2009)
“WeiHua” Grant-in Aid (2010)
Other：
One of the First Prize Award Winners of the Chorus Competition
in Hubei province（2007-2008）
Champion in 800-meter of School Sports (2009)
Second in 200-meter of School Sports (2009)
“Excellent Students” of Party School (2008)
“Excellent Students” of School (2008、2009)
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