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1、材料专业英语翻译主讲:林建国课程简介:课堂6学时,课后14学时考试:开卷,当堂完成主要内容及课时安排Introductiontomaterialsscienceandengineering(4学时)Metallicmaterialsandalloys(4学时)Ceramics(2学时)Composites(2学时)Nanostructuredmaterials(2学时)Part1IntroductiontomaterialsscienceandengineeringUnit1Physicalandchemicalpropertiesofma
2、terialsUnit2MechanicalpropertiesofmaterialsUnit1PhysicalandchemicalpropertiesofmaterialsPhysicalpropertiesarethosethatcanbeobservedwithoutchangingtheidentityofthesubstance.Thegeneralpropertiesofmattersuchascolor,density,hardness,areexamplesofphysicalproperties.Propertiesth
3、atdescribehowasubstancechangesintoacompletelydifferentsubstancearecalledchemicalproperties.Flammabilityandcorrosion/oxidationresistanceareexamplesofchemicalproperties.Ingeneral,someofthemoreimportantphysicalandchemicalpropertiesfromanengineeringmaterialstandpointincludepha
4、setransformationtemperatures,density,specificgravity,thermalconductivity,linearcoefficientofthermalexpansion,electricalconductivityandresistivity,magneticpermeability,andcorrosionresistance,andsoon.磁导率PhaseTransformationTemperaturesWhentemperaturerisesandpressureisheldcons
5、tant,atypicalsubstancechangesfromsolidtoliquidandthentovapor.Transitionsfromsolidtoliquid,fromliquidtovapor,fromvaportosolidandvisaversaarecalledphasetransformationsortransitions.Sincesomesubstanceshaveseveralcrystalforms,technicallytherecanbesolidtoanothersolidfromphasetr
6、ansformation.Meltingpoint:thephasetransitiontemperaturewhereasolidchangestoaliquidBoilingpoint:thetemperatureatwhichthevaporpressureofaliquidequals1atm(101.3kPa)Somematerials,suchasmanypolymers,donotgosimplyfromasolidtoaliquidwithincreasingtemperature.Instead,atsometempera
7、turebelowthemeltingpoint,theystarttolosetheircrystallinestructurebutthemoleculesremainlinkedinchains,whichresultsinasoftandpliablematerial.Thetemperatureatwhichasolid,glassymaterialbeginstosoftenandflowiscalledtheglasstransitiontemperature.DensityMasscanbethinlydsitrbuteda
8、sinapillow,ortightlypackedasinablockoflead.质量可以像枕头似地稀疏地分布,也可以像铅那样紧紧地堆积在一起。Thespacethemass