材料科学与工程专业英语

材料科学与工程专业英语材料科学与工程专业英语江苏大学材料学院主讲：杨娟13655280207材料科学与工程专业英语课程简介•共20学时（课堂14学时，课后6学时）•考试：开卷，当堂完成•教材：《材料科学与工程专业英语》第二版匡少平、王世颖主编，化学工业出版社.材料科学与工程专业英语主要内容和课时安排•Introductiontomaterialsscienceandengineering(4学时)•Metallicmaterialsandalloys（4学时）•Ceramics（2学时）•Polymer（2学时）•Composites（2学时）•Nanostructuredmaterials（2学时）材料科学与工程专业英语Part1Introductiontomaterialsscienceandengineering•Unit1Physicalandchemicalpropertiesofmaterials•Unit2Mechanicalpropertiesofmaterials材料科学与工程专业英语Unit1Physicalandchemicalpropertiesofmaterials•Physicalpropertiesarethosethatcanbeobservedwithoutchangingtheidentityofthesubstance.Thegeneralpropertiesofmattersuchascolor,density,hardness,areexamplesofphysicalproperties.Propertiesthatdescribehowasubstancechangesintoacompletelydifferentsubstancearecalledchemicalproperties.Flammabilityandcorrosion/oxidationresistanceareexamplesofchemicalproperties.材料科学与工程专业英语•Ingeneral,someofthemoreimportantphysicalandchemicalpropertiesfromanengineeringmaterialstandpointincludephasetransformationtemperatures,density,specificgravity,thermalconductivity,linearcoefficientofthermalexpansion,electricalconductivityandresistivity,magneticpermeability,andcorrosionresistance,andsoon.磁导率材料科学与工程专业英语PhaseTransformationTemperatures•Whentemperaturerisesandpressureisheldconstant,atypicalsubstancechangesfromsolidtoliquidandthentovapor.Transitionsfromsolidtoliquid,fromliquidtovapor,fromvaportosolidandvisaversaarecalledphasetransformationsortransitions.Sincesomesubstanceshaveseveralcrystalforms,technicallytherecanbesolidtoanothersolidfromphasetransformation.材料科学与工程专业英语Meltingpoint:thephasetransitiontemperaturewhereasolidchangestoaliquidBoilingpoint:thetemperatureatwhichthevaporpressureofaliquidequals1atm(101.3kPa)材料科学与工程专业英语Somematerials,suchasmanypolymers,donotgosimplyfromasolidtoaliquidwithincreasingtemperature.Instead,atsometemperaturebelowthemeltingpoint,theystarttolosetheircrystallinestructurebutthemoleculesremainlinkedinchains,whichresultsinasoftandpliablematerial.Thetemperatureatwhichasolid,glassymaterialbeginstosoftenandflowiscalledtheglasstransitiontemperature.材料科学与工程专业英语Density•Masscanbethinlydsitrbutedasinapillow,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。•Thespacethemassoccupiesisitsvolume,andthemassperunitofvolumeisitsdensity.材料科学与工程专业英语•Mass(m)isafundamentalmeasureoftheamountofmatter.Weight(w)isameasureoftheforceexertedbyamassandthisforceisproducedbytheaccelerationofgravity.•Therefore,onthesurfaceofearth,themassofanobjectisdeterminedbydividingtheweightofanobjectby9.8m/s2(theaccelerationofgravityonthesurfaceoftheearth).因此，在地球表面，物体的质量由物体的重量和重力加速度所决定。Sincewearetypicallycomparingthingsonthesurfaceoftheearth,theweightofanobjectiscommonlyusedratherthancalculatingitsmass.材料科学与工程专业英语•Thedensity(r)ofamaterialdependsonthephaseitisinandthetemperature(thedensityofliquidsandgasesisverytemperaturedependent).Waterintheliquidstatehasadensityof1g/cm3at4℃.Icehasadensityof0.9171g/cm3at0℃,anditshouldbenotedthatthisdecreaseindensityforthesolidphaseisunusual.Foralmostallothersubstances,thedensityofthesolidphaseisgreaterthanthatoftheliquidphase.Watervaporhasadensityof0.051g/cm3.材料科学与工程专业英语SpecificGravity•Specificgravityistheratioofdensityofasubstancecomparedtothedensityoffreshwaterat4℃.Atthistemperaturethedensityofwaterisatitsgreatestvalueandequalto1g/mL.•Sincespecificgravityisaratio,soithasnounits.Anobjectwillfloatinwaterifitsdensityislessthanthedensityofwaterandsinkifitsdensityisgreaterthanthatofwater.材料科学与工程专业英语•Similarly,anobjectwithspecificgravitylessthan1willfloatandthosewithaspecificgravitygreaterthan1willsink.•SpecificgravityvaluesforafewcommonsubstancesareAu,19.3;mercury,13.6;alcohol,0.7893;benzene,0.8786.•Notethatsincewaterhasdensityof1g/cm3,thespecificgravityisthesameasthedensityofthematerialmeasureding/cm3.材料科学与工程专业英语MagneticPermeability•Magneticpermeabilityorsimplypermeabilityistheeasewithwhichamaterialcanbemagnetized.Itisaconstantofproportionalitythatexistsbetweenmagneticinductionandmagneticfieldintensity.磁感应强度磁场强度材料科学与工程专业英语•Thisconstantisequaltoapproximately1.257×10-6Henrypermeter(H/m)infreespace(avacuum).Inothermaterialsitcanbemuchdifferent,oftensubstantiallygreaterthanthefree-spacevalue,whichissymbolized0.•其他材料却截然不同，通常远大于真空值。材料科学与工程专业英语•Materialsthatcausethelinesoffluxtomovefartherapart,resultinginadecreaseinmagneticfluxdensitycomparedwithavacuum,arecalleddiamagnetic.Materialsthatconcentratemagneticfluxbyafactorofmorethanonebutlessthanorequaltotenarecalledparamagnetic;materialsthatconcentratethefluxbyafactorofmorethantenarecalledferromagnetic.Thepermeabilityfactorsofsomesubstanceschangewithrisingorfallingtemperature,orwiththeintensityoftheappliedmagneticfield.材料科学与工程专业英语Exercises•TranslatethefollowingintoChinesePhasetransformationtemperaturesSpecificgravityThermalconductivityThemeltingpointTheaccelerationofgravityMagneticpermeabilityMagneticlinesoffluxferromagnetic材料科学与工程专业英语•TranslatethefollowingintoEnglish•相对密度沸点磁感应•热导率玻璃转变温度有色金属•线性热膨胀系数单位体积质量材料科学与工程专业英语Unit2MechanicalPropertiesofMaterials•Themechanicalproperties