材料科学概论

IntroductiontoMaterialsScienceandEngineeringGuanRui-fang1精选ppt2精选ppt材料与新技术革命3精选ppt4精选ppt5精选ppt6精选ppt7精选ppt材料与国防现代化8精选pptThisbookisdividedintofourmajorsectionsThefundamentalsThestructuralmaterialsTheelectronicandmagneticmaterialsMaterialsinengineeringdesignsciencematerialsengineering9精选pptNatureofmaterials’propertiesMicroscopicorsubmicroscopicstructureEngineeringdesign10精选pptChapterI

MaterialsforEngineering1.1Typesofmaterials1.2Fromstructuretoproperties1.3Selectionofmaterials1.4Materialsscienceandengineering11精选pptKeywordAlloy[5AlCi]

Atomic-scale-architectureBrittle[5britl]Ceramic[si5rAmik]Composite[5kCmpEzit,-zait]Concrete[5kCnkri:t]ConductorCrystalline[5kristElain]adj.Devitrified[di:5vitrifai]Ductility[dQk5tiliti]ElectronicandmagneticmaterialElement[5elimEnt]Fiberglass[5faIbE^lB:s]12精选pptGlassGlass-ceramicInsulatorMaterialsscienceandengineeringMaterialsselectionMetallicMicrocircuitry[5maIkrEJs\:kIt]Microscopic-scalearchitectureNoncrystallineNonmetallic[5nCnmi5tAlik]Keyword13精选pptOxidePeriodic[piEri5Cdik]tablePlasticPolyethylene[7pCli5eWili:n]PolymerPropertyRefractorySemiconductorSilica硅石，SiO2Silicate]硅酸盐Silicon硅元素SteelStructuralmaterialwoodKeyword14精选ppt1.1Typesofmaterials

a.Metalsmetallicbondb.Ceramics(glass)ionic[aI5RnIk]andcovalent[kEu5veilEnt]bondc.PolymerscovalentandVanderwaalsbondd.Compositese.semiconductorsWhatmaterialsareavailabletome?Fivecategories15精选ppt16精选pptAMetals

超塑性的,超塑性材料(制)的1.i.e.Latin，thewrittenabbreviationforidest,也就是，即。读作：thatis2.state-of-the-art技术发展水平，现代化的。3.superplastic.17精选pptCharacteristics(metallic金属的，金属性的)Itisstrongandcanbereadilyformedintopracticalshapes.Ductile[5dQktail]—permanentdeformabilitymetalliclusterelectricconductor

Metalshavenobrittlenessandaresafeformanyapplications.Structuralsteel18精选pptGasket[5^Askit]垫圈,衬垫springwireValve[vAlv]19精选ppt20精选ppt21精选ppt22精选pptBCeramics[si5rAmiks]Ahomogeneousmixtureoftwoormoresubstances,whichmaybesolids,liquids,gases,oracombinationofthese.1.Refractory[ri5frAktEri]Difficulttomeltorwork;resistanttoheat.2.fracturetoughness断裂韧度3.crystalline[5kristElain]Being,relatingto,orcomposedofcrystalorcrystals.4.Devitrify[di:5vitrifai]Tocause(aglassymaterial)tobecomecrystallineandbrittle.5.solution23精选pptTheceramicsisderivedfromGreekword“keramic”whichmeansanartofpotter.Include:

glass;enamels[i5nAmEl];refractories;cements;limes;plasters(plasterofParis);cermets[5sE:met]金属陶瓷,含陶合金;electronicceramics;highandlowtensionelectricalinsulators;structuralclayproducts;nuclearceramics;whitewares;abrasives[E5breisiv].24精选pptTheDifferentColorsofCorundum[kE5rQndEm]RubySapphire[5sAfaiE]25精选ppt

Whyshouldn’tAl2O3bechosenforcertainapplicationswheremetallicaluminumhasbeenused?1、Al2O3havetwoadvantages:first,chemicallystable;Aloxidizedsecond,highermeltingpoint(20200C)Al(6600C)refractoryuseinindustrialfurnace

construction26精选pptQuestionsWhatmaterialsareavailabletoyouinthisbook?Whatfundamentalcharacteristicsmetalshave?Pleaseshademetallicelementsinperiodictableandgivesomeexamplesofalloys.PleaselisttwoprincipaladvantagesofAl2O3relativetometallicAl.What’sthemostlimitingpropertyofceramics.27精选pptThemostlimitingpropertyofceramicsbrittlenessRecentdevelopmentinceramictechnologyareexpandingtheutilityofceramicsforstructuralapplicationnotbyeliminatingtheirinherentbrittleness,butbyincreasingtheirstrengthtosufficientlyhighlevels(greaterthan700MPa)andincreasingtheirresistancetofracture.28精选ppt2、Al2O3MgOSiO2Si3N4Atleastonemetallicelement+oneoffivenonmetalelement(C,N,O,PandS)Carbide[5kB:baid]Nitride[5naitraid]Oxide[5Cksaid]Phosphide[5fCsfaid]Sulphide.[5sQlfaid]OxideceramicsNonoxideceramics29精选ppt3、Onemetallicelementplusoneoffivenonmetallicelements(C,N,O,P,orS)30精选ppt4、Characteristics:refractoryhighhardnesshighstrengthhighbrittleness31精选ppt32精选ppt33精选pptThesimilarstructuralfeatureofmetalsandceramics:Crystalline:theirconstituentatomsarestackedtogetherinaregular,repeatingpattern.Thedistinction:ceramicscanbemadeinanoncrystallineform.[skI5mAtIk]34精选pptSiO2(approximately72%)Na2OCaOGlass:brittlenesssimilarwithcrystallineceramictransmitvisiblelightchemicalinertnessglassesareimportantengineeringmaterials35精选pptGlass-ceramicsisathirdcategoryLithiumaluminosilicatesCertainglasscompositionscanbefullydevitifiedbyanappropriatethermaltreatmentlow-thermalexpansioncoefficientscomplexformshighmechanicalstrengthVitreous[5vItrIEs]glassystateSubsequentcrystallization36精选ppt37精选ppt38精选pptCPolymers(plastics)Exempligratia.Forexample.1.ethylene

Acolorless,flammablegas,C2H4,derivedfromnaturalgasandpetroleumandusedasasourceofmanyorganiccompounds,inwelding

[5weldiN]焊接andcuttingmetals,andasananesthetic

[7Anis5Wetik]麻醉剂.2.polyethyleneApolymerizedethyleneresin,usedespeciallyforcontainers,kitchenware,andtubing,orintheformoffilmsandsheetsforpackaging.3.e.g.39精选pptAnyofnumerousorganiccompounds,suchasbenzeneandmethane,thatcontainonlycarbonandhydrogen.4.Acrylics[E5kriliks]丙烯酸树脂5.Nylon[5nailEn]Anyofafamilyofhigh-strength,resilientsyntheticpolymers,themoleculesofwhichcontaintherecurringamidegroupCONH.6.Hydrocarbon40精选pptTheseman-madematerialsareabranchoforganicchemistry.41精选ppt42精选ppt1.Poly+mer:merinapolymerisasinglehydrocarbonmoleculesuchasethylene(C2H4).longchainolecules:Polymersarelong-chainmoleculescomposedofmanymersbondtogether.43精选ppt44精选ppt1)nobrittleness2.Characteristics:2)lowermeltingpoint3)highstrengthalongit’schainandlowstrengthbetweenit’schains4)lightweightlow-cost5)higherchemicalreactivity6)Man-madematerials45精选pptSubstitutionfortraditionalstructuralmetals46精选pptQustionspleaseillustratetwotypeofelementsthatcomposedceramiccompoundsinperiodictable.Whatarethemajorcompositionsofglass?whyglassesareimportantengineeringmaterials?Pleaselisttwocategoriesandgivesomeexamplesofceramicsaccordingtheircompositions.Pleaselistthreecategoriesandgivesomeexamplesofceramicsaccordingtheiratomicstructrualfeature.Whatarepolymers?Whatarecharacteristicsofpolymers?Pleasegivesomeexamplesofpolymers.47精选ppt48精选pptSiO2(approximately72%)Na2OCaOGlass:brittlenesssimilarwithcrystallineceramictransmitvisiblelightchemicalinertnessglassesareimportantengineeringmaterials49精选pptAccordingtotheircompositions,ceramicscanbedividedintotwocatogories.Oneisoxideceramicssuchasaluminumoxide(Al2O3),magnesiumoxide(MgO),andsilica(SiO2),theotheroneisnonoxideceramics,siliconnitrideisanimportantnonoxideceramic.50精选pptaccordingtotheiratomicstructualfeature,therearethreetypesofceramicsascrystallineceramics,noncrystallineceramicsandthethirdcategory,glass-ceramics.Siliconnitrideisoneofcrystallineceramics,glassisakindofnoncrystallineceramicsandglass-ceramicsisarelativelyrecentmaterial,thatis,certainglasscompositions(suchaslithiumaluminosilicates)canbefullydevitifiedbyanappropriatethermaltreatment.51精选ppt

Polymersarelong-chainmoleculescomposedofmanymersbondtogether.Polyethylene,acrylicsandnylonarealltypicalpolymers.Polymersarenobrittleness,highstrengthalongit’schainandlowstrengthbetweenit’schains,lightweight,low-cost,lowermeltingpointandhigherchemicalreactivitycomparedwithceramics,atlastpolymersareman-madematerials.52精选pptshell53精选pptwood54精选ppt55精选ppt56精选pptDComposite(fiberreinforceplastics)Possessinghereditary[hI5redItErI]rankinapoliticalsystemorsocialclassderivedfromafeudalistic[9fjU:dE`lIstIk]stageofacountry'sdevelopment.

Inactiveorinert.1.Albeit[C:l5bi:It]page12,line5Eventhough;although;notwithstanding.2.Noblepage12,para.2,line257精选pptCombinationofindividualmaterialsfromthepreviouscategories.Characteristics:thebestofbothworldsItcarryalongthesuperiorpropertiesofeachcomponent,producingaproductthatissuperiortoeitherofthecomponentsseparately.58精选pptExample:fiberglass,wood,concrete.59精选ppt60精选ppts61精选pptSupplementaryintroductionSemiconductorsApieceofequipmentthatproducesapowerfulnarrowbeamoflightthatcanbeusedinmedicaloperations,tocutmetals,ortomakepatternsoflightforentertainment.1.arsenide[5B:sEnaid]砷化物Acompoundofarsenicwithamoreelectropositiveelement.2.laser62精选pptSophisticated

page13，line6frombelow[sE5fistikeitid]adj.1.诡辩的,久经世故的2.Verycomplexorcomplicated:非常复杂精密或尖端的最新最尖端的技术thelatestandmostsophisticatedtechnology.63精选pptSemiconductorsarerelativelyinvisiblecomparedwithpolymers,buthaveacomparablesocialimpact.Semiconductorsarethebasisofmodernelectronics.64精选ppt65精选pptArelativelysmallgroupofelementsandcompoundshasanimportantelectricalproperty。threesemiconductingelements

(Si(silicon),Ge(germanium[dVE:5meiniEm]),Sn(tin)).compounds:GaAs

gallium

[5^AliEm]arsenide,

CdS

cadmium

sulfide[5kAdmiEm

5sQlfaid]ceramicscompound:ZnOPrecisecontrolofchemicalpurityallowsprecisecontrolofelectronicproperties.66精选pptCharacteristics:

semiconduction,inwhichtheyareneithergoodelectricalconductorsnorgoodelectricalinsulators

[5insjuleitE],instead,theirabilitytoconductelectricityisintermediate

[7intE5mi:djEt].67精选pptAtomic-scale-architectureCompositeDevitrified[di:5vitrifai]使不透明DuctilityElectronicandmagneticmaterialFiberglassMaterialsselectionMicrocircuitry

[5maIkrEJs\:kIt][电子]微电路Microscopic-scalearchitectureRefractoryStructuralmaterial68精选pptQustions1、Pleasedefinecomposites,andthendemonstratethecharacteristicsofgoodcompositesbysomeexamples.2、pleaseenumerate([i5nju:mEreit]v.列举)semiconductingelementsandcompounds.69精选pptCompositeismaterialcomposedofamicroscopic-scalecombinationofindividualmaterialsfromthecategoriesofmetals,ceramics(andglasses),andpolymer.E.g.fiberglassisakindofcompositesystemcomposedofpolymericmatrixreinforcedwithglassfibers.Characteristicoffiberglassprovidesthebestofbothworlds:Itcarryalongthesuperiorpropertiesofeachcomponent,producingaproductthatissuperiortoeitherofthecomponentsseparately.Thehighstrengthofthesmall-diameterglassfibersiscombinedwiththeductilityofthepolymermatrixtoproduceastrongmaterialcapableofwithstandingthenormalloadingrequiredofastructuralmaterial.70精选pptTherearethreesemiconductingelements(Si,GeandSn)fromcolumnIVAandaclusterofelementsoftheperiodictableimmediatelyadjacenttocolumnIVA,whichformscompoundsthataresemiconducting.Examplesincludegalliumarsenide(GaAs),whichisusedasahigh-temperaturerectifier([5rektifaiE]整流器)andalasermaterial,andcadmiumsulfide(CdS)whichisusedasarelativelylow-costsolarcellforconversionofsolarenergytousefulelectricalenergy.71精选ppt1.2FromstructuretopropertiesTheunitofluminousflux[flQks]流量,通量intheInternationalSystem,equaltotheamountoflightgivenoutthroughasolidanglebyasourceofonecandela[kAn5di:lE]intensityradiatingequallyinalldirections.1.hexagonal[hek`sA^EnEl]Havingsixsides.2.lumen[5lju:min]缩写lm[物理学]流明（光通量单位）：国际度量系统中的光通量单位，等于一烛光的均匀点光源在单位主体角内发出的光通量.72精选pptEquivalent[i5kwivElEnt]adj.相等的,相当的,同意义的等价物,相等物Avenue[5Avinju:]n.林荫道,大街,方法,途径,路Refraction[ri5frAkFEn]n.折光,折射Determinationoftherefractivecharacteristicsoftheeye.

屈光度测定：对眼睛折射特性的测定73精选pptTranslucent[trAnz5lju:snt]adj.半透明的,透明的Opaque[Eu5peik]n.不透明物adj.不透明的,不传热的,迟钝的Transparent[trAns5pZErEnt]adj.透明的,显然的,明晰的Densification[7densifi5keiFEn]致密化74精选pptTounderstandthepropertiesofengineeringmaterialsitisnecessarytounderstandtheirstructure.75精选pptAtomic-scalearchitecture10000000timesMicroscopic-scalearchitecture1000times76精选pptExample1:Al,MgAlalloysareductileMgalloysarebrittle77精选pptAlstructurefollowsacubicpackingarrangementandMgahexagonalone.78精选ppt79精选ppt80精选pptExample2:transparentceramicsTraditionalceramicscontainedasubstantialamountofresidualporosity.Theporosityleadstolossofvisiblelighttransmission.Onlyabout0.3%porositycancauseAl2O3tobetranslucent,and3%porositycancausethematerialtobecompletelyopaque.Theeliminationofporosity:addingasmallamountofimpurity.81精选pptTheeliminationofporosityresultedfromarelativelysimpleinventionthatinvolvedaddingasmallamountofimpurity(0.1wt%MgO),whichcausedthehigh-temperaturedensificationprocessfortheAl2O3powdertogotocompletion.82精选pptPorosmicrostructureinpolycrystallineAl2O383精选pptFigure1

polycrystallinefacetedsapphiresandrubiesFigure3

polisheddiscswithseveraldopants(thickness:0.8mm)84精选ppt85精选pptThetwoexamplesjustcitedshowtypicalandimportantdemonstrationsofhowpropertiesofengineeringmaterialsfollowdirectlyfromstructure.86精选pptQustions1.Aluminumandmagnesiumarebothmetal,whyaluminumisrelativelyductilewhilemagnesiumisrelativelybrittle?Pleaseexplainthedramaticeffectthatstructurehasonpropertiesontheatomicscale.2.whytraditionalceramicssuchasaluminumoxideareopaquewhereasrecentlyopticallytransparentaluminumoxideceramicsareproduced?Whatarethedifferencesbetweentheirmicroscopic-scalearchitectures?87精选ppt1.3Selectionofmaterials

anyofagroupofverystronglightweight,syntheticfibersusedinmakingradialtires,bulletproofofvests,etc.1.etc.

Latinthewrittenabbreviationforetcetera,usedafteralisttoshowthattherearemanyothersimilarthingsorpeoplethatyoucouldhaveadded.andsoforth,andsoon,andtheothers2.ASTMAmericanSocietyforTestingandMaterials.3.aramid88精选ppt

Apolymercontainingrepeatedamidegroups,asinvariouskindsofnylon.

4.Aromatic[7ArEu5mAtik]Of,relatingto,orcontainingoneormoresix-carbonringscharacteristicofthebenzene[5benzi:n,ben5zi:n]seriesandrelatedorganicgroups.5.Polyamide89精选pptAppreciation[E7pri:Fi5eiFEn]n.Ajudgmentoropinion,especiallyafavorableone。评价：判断或意见，尤指有益的。2.Materialsselectionisthefinal,practicaldecisionintheengineeringdesignprocessandcandeterminethatdesign’sultimatesuccessorfailure.3.solid-stateadj.使用电晶体的,不用真空管的4.indefinite[in5definit]adj.不确定的,[语]不定的(indefinitearticle)90精选ppt5.althoughsomestructuralceramicscanwithstandtheanticipatedserviceload,……serviceload负载6.criterion[krai5tiEriEn]n.(批评判断的)标准,准据,规范critical[5kritikEl]adj.评论的,鉴定的,批评的,危急的,临界的91精选ppt7.Theaddedcostoffabricatingthesemoresophisticatedmaterialsystemsisjustifiedonlyifaspecialadvanta