吉林大学材料科学基础.ppt

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1、Fundamentalsofmaterialsscienceandengineering材料科学与工程基础SchoolofmaterialsScienceandEngineering材料科学与工程学院IntroductionChapter1Historically,thedevelopmentandadvancementofsocietieshavebeenintimatelytiedtothemembers’abilitytoproduceandmanipulatematerialstofilltheirneeds.Infact,earlycivil

2、izationshavebeendesignatedbytheleveloftheirmaterialsdevelopmentMaterialsareprobablymoredeep-seatedinourculturethanmostofusrealize.1.1HistoricalPerspectiveStoneageBronzeageIronageSteelageAdvancedmaterialageStoneBronze(Cu-Snalloy)中国商代司母戊大方鼎(公元前14~11世纪)IronStructuresMaterialsscien

3、cePropertiesinvestigatingrelationshipsDesigningorengineeringthestructureofamaterialtoproduceapredeterminedsetofpropertiesOnthebasisofthesecorrelationsMaterialsengineering1.2MaterialsScienceandEngineeringSubatomicstructure(原子内)involveselectronswithintheindividualatomsandinteracto

4、nswiththeirnucleiAtomiclevelstructure(原子间)encompassestheorganizationofatomsormoleculesrelativetooneanother“Structure”ofamaterialusuallyrelatestothearrangementofitsinternalcomponents.Microscopicstructurelargerstructuralrealmcontainslargegroupsofatomsthatarenormallyagglomeragedt

5、ogetherbesubjecttodirectobservationusingsometypeofmicroscopeMacroscopicstructurethestructuralelementsthatmaybeviewedwiththenakedeye“Property”:whileinserviceuse,allmaterialsareexposedtoexternalstimulationthatevokesometypeofresponse.Forexample:SubjectedtoforcedeformationPolished

6、metalsurfacereflectlightGenerally,definitionsofpropertiesaremadeindependentofmaterialshapeandsizeMechanicalpropertiesElectricalpropertiesThermalbehaviorMagneticpropertiesOpticalpropertiesDeteriorativecharacteristicsSixdifferentimportantpropertiesStimulusResponseAppliedloadorfor

7、ceelasticmodulusandstrength…ElectricfieldElectricalconductivityDielectricconstant…TemperatureHeatcapacityThermalconductivity…MagneticfieldElectromagneticorlightradiationIndexofrefractionReflectivity…ServiceconditionChemicalreactivityofmaterialsThereisacharacteristictypeofstuimul

8、uscapableofprovokingdifferentresponsesStructure