材料科学概论

IntroductiontoMaterialsScienceandEngineering GuanRui fang 材料与新技术革命 材料与国防现代化 ThisbookisdividedintofourmajorsectionsThefundamentalsThestructuralmaterialsTheelectronicandmagneticmaterialsMaterialsinengineeringdesign Natureofmaterials properties Microscopicorsubmicroscopicstructure Engineeringdesign ChapterIMaterialsforEngineering 1 1Typesofmaterials1 2Fromstructuretoproperties1 3Selectionofmaterials1 4Materialsscienceandengineering Keyword Alloy 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 GlassGlass ceramicInsulatorMaterialsscienceandengineeringMaterialsselectionMetallicMicrocircuitry 5maIkrEJs kIt Microscopic scalearchitectureNoncrystallineNonmetallic 5nCnmi5tAlik Keyword OxidePeriodic piEri5Cdik tablePlasticPolyethylene 7pCli5eWili n PolymerPropertyRefractorySemiconductorSilica硅石 SiO2Silicate 硅酸盐Silicon硅元素Steel Structuralmaterialwood Keyword 1 1Typesofmaterials a Metalsmetallicbondb Ceramics glass ionic aI5RnIk andcovalent kEu5veilEnt bondc PolymerscovalentandVanderwaalsbondd Compositese semiconductors Whatmaterialsareavailabletome Fivecategories AMetals 超塑性的 超塑性材料 制 的 1 i e Latin thewrittenabbreviationforidest 也就是 即 读作 thatis 2 state of the art 技术发展水平 现代化的 3 superplastic Characteristics metallic金属的 金属性的 Itisstrongandcanbereadilyformedintopracticalshapes Ductile 5dQktail permanentdeformabilitymetalliclusterelectricconductorMetalshavenobrittlenessandaresafeformanyapplications Structuralsteel Gasket 5 Askit 垫圈 衬垫 spring wire Valve vAlv BCeramics 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 solution TheceramicsisderivedfromGreekword 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 TheDifferentColorsofCorundum kE5rQndEm Ruby Sapphire 5sAfaiE Whyshouldn tAl2O3bechosenforcertainapplicationswheremetallicaluminumhasbeenused 1 Al2O3havetwoadvantages first chemicallystable Aloxidized second highermeltingpoint 20200C Al 6600C refractory useinindustrialfurnaceconstruction Questions Whatmaterialsareavailabletoyouinthisbook Whatfundamentalcharacteristicsmetalshave Pleaseshademetallicelementsinperiodictableandgivesomeexamplesofalloys PleaselisttwoprincipaladvantagesofAl2O3relativetometallicAl What sthemostlimitingpropertyofceramics Themostlimitingpropertyofceramics brittleness Recentdevelopmentinceramictechnologyareexpandingtheutilityofceramicsforstructuralapplicationnotbyeliminatingtheirinherentbrittleness butbyincreasingtheirstrengthtosufficientlyhighlevels greaterthan700MPa andincreasingtheirresistancetofracture 2 Al2O3MgOSiO2Si3N4 Atleastonemetallicelement oneoffivenonmetalelement C N O PandS Carbide 5kB baid Nitride 5naitraid Oxide 5Cksaid Phosphide 5fCsfaid Sulphide 5sQlfaid Oxideceramics Nonoxideceramics 3 Onemetallicelementplusoneoffivenonmetallicelements C N O P orS 4 Characteristics refractory highhardness highstrength highbrittleness Thesimilarstructuralfeatureofmetalsandceramics Crystalline theirconstituentatomsarestackedtogetherinaregular repeatingpattern Thedistinction ceramicscanbemadeinanoncrystallineform skI5mAtIk SiO2 approximately72 Na2OCaO Glass brittleness similarwithcrystallineceramic Glass ceramicsisathirdcategoryLithiumaluminosilicatesCertainglasscompositionscanbefullydevitifiedbyanappropriatethermaltreatment low thermalexpansioncoefficients complexforms highmechanicalstrength Vitreous 5vItrIEs glassystate Subsequentcrystallization CPolymers plastics Exempligratia Forexample 1 ethylene Acolorless flammablegas C2H4 derivedfromnaturalgasandpetroleumandusedasasourceofmanyorganiccompounds inwelding 5weldiN 焊接andcuttingmetals andasananesthetic 7Anis5Wetik 麻醉剂 2 polyethylene Apolymerizedethyleneresin usedespeciallyforcontainers kitchenware andtubing orintheformoffilmsandsheetsforpackaging 3 e g Anyofnumerousorganiccompounds suchasbenzeneandmethane thatcontainonlycarbonandhydrogen 4 Acrylics E5kriliks 丙烯酸树脂 5 Nylon 5nailEn Anyofafamilyofhigh strength resilientsyntheticpolymers themoleculesofwhichcontaintherecurringamidegroupCONH 6 Hydrocarbon Theseman madematerialsareabranchoforganicchemistry 1 Poly mer merinapolymerisasinglehydrocarbonmoleculesuchasethylene C2H4 longchainolecules Polymersarelong chainmoleculescomposedofmanymersbondtogether 1 nobrittleness 2 Characteristics 2 lowermeltingpoint 3 highstrengthalongit schainandlowstrengthbetweenit schains 4 lightweightlow cost 5 higherchemicalreactivity 6 Man madematerials Substitutionfortraditionalstructuralmetals Qustions pleaseillustratetwotypeofelementsthatcomposedceramiccompoundsinperiodictable Whatarethemajorcompositionsofglass whyglassesareimportantengineeringmaterials Pleaselisttwocategoriesandgivesomeexamplesofceramicsaccordingtheircompositions Pleaselistthreecategoriesandgivesomeexamplesofceramicsaccordingtheiratomicstructrualfeature Whatarepolymers Whatarecharacteristicsofpolymers Pleasegivesomeexamplesofpolymers SiO2 approximately72 Na2OCaO Glass brittleness similarwithcrystallineceramic Accordingtotheircompositions ceramicscanbedividedintotwocatogories Oneisoxideceramicssuchasaluminumoxide Al2O3 magnesiumoxide MgO andsilica SiO2 theotheroneisnonoxideceramics siliconnitrideisanimportantnonoxideceramic accordingtotheiratomicstructualfeature therearethreetypesofceramicsascrystallineceramics noncrystallineceramicsandthethirdcategory glass ceramics Siliconnitrideisoneofcrystallineceramics glassisakindofnoncrystallineceramicsandglass ceramicsisarelativelyrecentmaterial thatis certainglasscompositions suchaslithiumaluminosilicates canbefullydevitifiedbyanappropriatethermaltreatment Polymersarelong chainmoleculescomposedofmanymersbondtogether Polyethylene acrylicsandnylonarealltypicalpolymers Polymersarenobrittleness highstrengthalongit schainandlowstrengthbetweenit schains lightweight low cost lowermeltingpointandhigherchemicalreactivitycomparedwithceramics atlastpolymersareman madematerials shell wood DComposite fiberreinforceplastics Possessinghereditary hI5redItErI rankinapoliticalsystemorsocialclassderivedfromafeudalistic 9fjU dE lIstIk stageofacountry sdevelopment Inactiveorinert 1 Albeit C l5bi It page12 line5 Eventhough although notwithstanding 2 Noblepage12 para 2 line2 Combinationofindividualmaterialsfromthepreviouscategories Characteristics thebestofbothworldsItcarryalongthesuperiorpropertiesofeachcomponent producingaproductthatissuperiortoeitherofthecomponentsseparately Example fiberglass wood concrete s SupplementaryintroductionSemiconductors Apieceofequipmentthatproducesapowerfulnarrowbeamoflightthatcanbeusedinmedicaloperations tocutmetals ortomakepatternsoflightforentertainment 1 arsenide 5B sEnaid 砷化物 Acompoundofarsenicwithamoreelectropositiveelement 2 laser Sophisticatedpage13 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 Semiconductorsarerelativelyinvisiblecomparedwithpolymers buthaveacomparablesocialimpact Semiconductorsarethebasisofmodernelectronics Arelativelysmallgroupofelementsandcompoundshasanimportantelectricalproperty threesemiconductingelements Si silicon Ge germanium dVE 5meiniEm Sn tin compounds GaAsgallium 5 AliEm arsenide CdScadmiumsulfide 5kAdmiEm5sQlfaid ceramicscompound ZnOPrecisecontrolofchemicalpurityallowsprecisecontrolofelectronicproperties Characteristics semiconduction inwhichtheyareneithergoodelectricalconductorsnorgoodelectricalinsulators 5insjuleitE instead theirabilitytoconductelectricityisintermediate 7intE5mi djEt Atomic scale architectureCompositeDevitrified di 5vitrifai 使不透明DuctilityElectronicandmagneticmaterialFiberglassMaterialsselectionMicrocircuitry 5maIkrEJs kIt 电子 微电路Microscopic scalearchitectureRefractoryStructuralmaterial Qustions 1 Pleasedefinecomposites andthendemonstratethecharacteristicsofgoodcompositesbysomeexamples 2 pleaseenumerate i5nju mEreit v 列举 semiconductingelementsandcompounds Compositeismaterialcomposedofamicroscopic scalecombinationofindividualmaterialsfromthecategoriesofmetals ceramics andglasses andpolymer E g fiberglassisakindofcompositesystemcomposedofpolymericmatrixreinforcedwithglassfibers Characteristicoffiberglassprovidesthebestofbothworlds Itcarryalongthesuperiorpropertiesofeachcomponent producingaproductthatissuperiortoeitherofthecomponentsseparately Thehighstrengthofthesmall diameterglassfibersiscombinedwiththeductilityofthepolymermatrixtoproduceastrongmaterialcapableofwithstandingthenormalloadingrequiredofastructuralmaterial Therearethreesemiconductingelements Si GeandSn fromcolumnIVAandaclusterofelementsoftheperiodictableimmediatelyadjacenttocolumnIVA whichformscompoundsthataresemiconducting Examplesincludegalliumarsenide GaAs whichisusedasahigh temperaturerectifier 5rektifaiE 整流器 andalasermaterial andcadmiumsulfide CdS whichisusedasarelativelylow costsolarcellforconversionofsolarenergytousefulelectricalenergy 1 2Fromstructuretoproperties Theunitofluminousflux 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 Equivalent 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 Translucent 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 Tounderstandthepropertiesofengineeringmaterialsitisnecessarytounderstandtheirstructure Atomic scalearchitecture10000000times Microscopic scalearchitecture1000times Example1 Al MgAlalloysareductileMgalloysarebrittle AlstructurefollowsacubicpackingarrangementandMgahexagonalone Example2 transparentceramicsTraditionalceramicscontainedasubstantialamountofresidualporosity Theporosityleadstolossofvisiblelighttransmission Onlyabout0 3 porositycancauseAl2O3tobetranslucent and3 porositycancausethematerialtobecompletelyopaque Theeliminationofporosity addingasmallamountofimpurity Theeliminationofporosityresultedfromarelativelysimpleinventionthatinvolvedaddingasmallamountofimpurity 0 1wt MgO whichcausedthehigh temperaturedensificationprocessfortheAl2O3powdertogotocompletion PorosmicrostructureinpolycrystallineAl2O3 Figure1polycrystallinefacetedsapphiresandrubies Figure3polisheddiscswithseveraldopants thickness 0 8mm Thetwoexamplesjustcitedshowtypicalandimportantdemonstrationsofhowpropertiesofengineeringmaterialsfollowdirectlyfromstructure Qustions 1 Aluminumandmagnesiumarebothmetal whyaluminumisrelativelyductilewhilemagnesiumisrelativelybrittle Pleaseexplainthedramaticeffectthatstructurehasonpropertiesontheatomicscale 2 whytraditionalceramicssuchasaluminumoxideareopaquewhereasrecentlyopticallytransparentaluminumoxideceramicsareproduced Whatarethedifferencesbetweentheirmicroscopic scalearchitectures 1 3Selectionofmaterials anyofagroupofverystronglightweight syntheticfibersusedinmakingradialtires bulletproofofvests etc 1 etc Latinthewrittenabbreviationforetcetera usedafteralisttoshowthattherearemanyothersimilarthingsorpeoplethatyoucouldhaveadded andsoforth andsoon andtheothers 2 ASTM AmericanSocietyforTestingandMaterials 3 aramid Apolymercontainingrepeatedamidegroups asinvariouskindsofnylon 4 Aromatic 7ArEu5mAtik Of relatingto orcontainingoneormoresix carbonringscharacteristicofthebenzene 5benzi n ben5zi n seriesandrelatedorganicgroups 5 Polyamide Appreciation 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 5 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 7 Theaddedcostoffabricatingthesemoresophisticatedmaterialsystemsisjustifiedonlyifaspecialadvantageresults fabrica