材料科学导论new

《材料科学导论new》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、材料科學導論材料科學導論IntroductionofMaterialsScienceIntroductionofMaterialsScience許正興國立聯合大學電機工程學系聯大電機系電子材料與元件應用實驗室1.Introduction2.IntroductionofMaterialsScienceandEngineering3.AtomicStructureandBonding4.CrystalStructuresandCrystalGeometry5.Solidification,CrystallineImpe

2、rfectionsandDiffusioninSolids6.PhaseDiagrams聯大電機系電子材料與元件應用實驗室CrystalStructuresandCrystalGeometrySolidmaybecategorizedbroadlyintocrystallineandamorphoussolids.Crystallinesolids,duetoorderlystructureoftheiratoms,molecules,orionspossesswell-definedshapes.=>Metalsarec

3、rystallineandarecomposedofwell-definedcrystalsorgrains.thegrainsaresmallandnotclearlyobservableduetotheopaquenatureofmetals.TheSpaceLatticeandUnitCellsIftheatomsorionsformasolidarearrangeinapatternthatrepeatsitselfinthreedimensions,theyformasolidthathaslong-rangeo

4、rder(LRO)andisreferredtoasacrystallinesolidorcrystallinematerial.=>metals,alloys,andsomeceramicmaterials.Somematerialswhoseatomsandionsarenotarrangedinalong-range,periodic,andrepeatablemannerandpossessonlyshort-rangeorder(SRO)=>thismeansthatorderexistsonlyintheimme

5、diateneighborhoodofanatomoramolecule.;suchasliquidwater=>amorphousornoncrystalline聯大電機系電子材料與元件應用實驗室Atomicarrangementsincrystallinesolidscanbedescribedbyreferringtheatomstothepointsofintersectionofanetworkoflinesinthreedimensions.Suchanetworkiscalledaspacelattice.=>

6、describedasaninfinitethree-dimensionalarrayofpoints.Inanidealcrystalthegroupingoflatticepointsaboutanygivenpointareidenticalwiththegroupingaboutanyotherlatticepointinthecrystallattice.Eachspacelatticecanthusbedescribedbyspecifyingtheatompositionsinarepeatingunitcel

7、l.Agroupofatomsorganizedinacertainarrangementrelativetoeachotherandassociatedwithlatticepointsconstituesthemotiforbasis.Thesizeandshapeoftheunitcellcanbedescribedbythreelatticevectorsa,bandc(axiallengtha,bandc;interaxialangle,and=>latticeconstantsofunitcell)聯大電

8、機系電子材料與元件應用實驗室CrystalSystemsandBravaisLatticeByassigningspecificvaluesforaxiallengthsandinteraxialangles,unitcellsofdifferenttypescanbeconstructe