机械材料与零件的介绍.doc

郑州工业应用技术学院 学生课程考核专业外文翻译 原 文：Machinery Design And Manufacturing?Related Materials?And Parts?Is Introduced 译 文：机械设计制造材料和零件的介绍 学 院： 机电工程学院 专 业： 机械设计制造及其自动化 班 级： 机械设计四班 课 程： 机械工程专业英语教程 学生姓名： 李东明 学 号： 1102130408 时 间： 2015年1月Machinery Design And Manufacturing?Related Materials?And Parts?Is Introduced Types?of?Materials?Materials?may?be?grouped?in?several?ways.?Scientists?often?classify?materials?by?their?state:?solid,?liquid,?or?gas.?They?also?separate?them?into?organic?(once?living)?and?inorganic?(never?living)?materials.? For?industrial?purposes,?materials?are?divided?into?engineering?materials?or?nonengineering?materials.?Engineering?materials?are?those?used?in?manufacture?and?become?parts?of?products. Nonengineering?materials?are?the?chemicals,?fuels,?lubricants,?and?other?materials?used?in?the?manufacturing?process,?which?do?not?become?part?of?the?product. Metals?are?elements?that?generally?have?good?electrical?and?thermal?conductivity.?Many?metals?have?high?strength,?high?stiffness,?and?have?good?ductility. Some?metals,?such?as?iron,?cobalt?and?nickel,?are?magnetic.?At?low?temperatures,? What?is?the?difference?between?an?alloy?and?a?pure?metal??Pure?metals?are?elements?which?come?from?a?particular?area?of?the?periodic?table.?Examples?of?pure?metals?include?copper?in?electrical?wires?and?aluminum?in?cooking?foil?and?beverage?cans. Alloys?contain?more?than?one?metallic?element.?Their?properties?can?be?changed?by?changing?the?elements?present?in?the?alloy.?Examples?of?metal?alloys?include?stainless?steel?which?is?an?alloy?of?iron,?nickel,?and?chromium;?and?gold?jewelry?which?usually?contains?an?alloy?of?gold?and?nickel. Some?metal?alloys,?such?as?those?based?on?aluminum,?have?low?