材料科学概论ppt课件

IntroductiontoMaterialsScienceandEngineering GuanRui fang 1 2 材料与新技术革命 3 4 5 6 7 材料与国防现代化 8 ThisbookisdividedintofourmajorsectionsThefundamentalsThestructuralmaterialsTheelectronicandmagneticmaterialsMaterialsinengineeringdesign 9 Natureofmaterials properties Microscopicorsubmicroscopicstructure Engineeringdesign 10 ChapterIMaterialsforEngineering 1 1Typesofmaterials1 2Fromstructuretoproperties1 3Selectionofmaterials1 4Materialsscienceandengineering 11 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 12 GlassGlass ceramicInsulatorMaterialsscienceandengineeringMaterialsselectionMetallicMicrocircuitry 5maIkrEJs kIt Microscopic scalearchitectureNoncrystallineNonmetallic 5nCnmi5tAlik Keyword 13 OxidePeriodic piEri5Cdik tablePlasticPolyethylene 7pCli5eWili n PolymerPropertyRefractorySemiconductorSilica硅石 SiO2Silicate 硅酸盐Silicon硅元素Steel Structuralmaterialwood Keyword 14 1 1Typesofmaterials a Metalsmetallicbondb Ceramics glass ionic aI5RnIk andcovalent kEu5veilEnt bondc PolymerscovalentandVanderwaalsbondd Compositese semiconductors Whatmaterialsareavailabletome Fivecategories 15 16 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 17 Characteristics metallic金属的 金属性的 Itisstrongandcanbereadilyformedintopracticalshapes Ductile 5dQktail permanentdeformabilitymetalliclusterelectricconductorMetalshavenobrittlenessandaresafeformanyapplications Structuralsteel 18 Gasket 5 Askit 垫圈 衬垫 spring wire Valve vAlv 19 20 21 22 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 23 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 24 TheDifferentColorsofCorundum kE5rQndEm Ruby Sapphire 5sAfaiE 25 Whyshouldn tAl2O3bechosenforcertainapplicationswheremetallicaluminumhasbeenused 1 Al2O3havetwoadvantages first chemicallystable Aloxidized second highermeltingpoint 20200C Al 6600C refractory useinindustrialfurnaceconstruction 26 Questions Whatmaterialsareavailabletoyouinthisbook Whatfundamentalcharacteristicsmetalshave Pleaseshademetallicelementsinperiodictableandgivesomeexamplesofalloys PleaselisttwoprincipaladvantagesofAl2O3relativetometallicAl What sthemostlimitingpropertyofceramics 27 Themostlimitingpropertyofceramics brittleness Recentdevelopmentinceramictechnologyareexpandingtheutilityofceramicsforstructuralapplicationnotbyeliminatingtheirinherentbrittleness butbyincreasingtheirstrengthtosufficientlyhighlevels greaterthan700MPa andincreasingtheirresistancetofracture 28 2 Al2O3MgOSiO2Si3N4 Atleastonemetallicelement oneoffivenonmetalelement C N O PandS Carbide 5kB baid Nitride 5naitraid Oxide 5Cksaid Phosphide 5fCsfaid Sulphide 5sQlfaid Oxideceramics Nonoxideceramics 29 3 Onemetallicelementplusoneoffivenonmetallicelements C N O P orS 30 4 Characteristics refractory highhardness highstrength highbrittleness 31 32 33 Thesimilarstructuralfeatureofmetalsandceramics Crystalline theirconstituentatomsarestackedtogetherinaregular repeatingpattern Thedistinction ceramicscanbemadeinanoncrystallineform skI5mAtIk 34 SiO2 approximately72 Na2OCaO Glass brittleness similarwithcrystallineceramic 35 Glass ceramicsisathirdcategoryLithiumaluminosilicatesCertainglasscompositionscanbefullydevitifiedbyanappropriatethermaltreatment low thermalexpansioncoefficients complexforms highmechanicalstrength Vitreous 5vItrIEs glassystate Subsequentcrystallization 36 37 38 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 39 Anyofnumerousorganiccompounds suchasbenzeneandmethane thatcontainonlycarbonandhydrogen 4 Acrylics E5kriliks 丙烯酸树脂 5 Nylon 5nailEn Anyofafamilyofhigh strength resilientsyntheticpolymers themoleculesofwhichcontaintherecurringamidegroupCONH 6 Hydrocarbon 40 Theseman madematerialsareabranchoforganicchemistry 41 42 1 Poly mer merinapolymerisasinglehydrocarbonmoleculesuchasethylene C2H4 longchainolecules Polymersarelong chainmoleculescomposedofmanymersbondtogether 43 44 1 nobrittleness 2 Characteristics 2 lowermeltingpoint 3 highstrengthalongit schainandlowstrengthbetweenit schains 4 lightweightlow cost 5 higherchemicalreactivity 6 Man madematerials 45 Substitutionfortraditionalstructuralmetals 46 Qustions pleaseillustratetwotypeofelementsthatcomposedceramiccompoundsinperiodictable Whatarethemajorcompositionsofglass whyglassesareimportantengineeringmaterials Pleaselisttwocategoriesandgivesomeexamplesofceramicsaccordingtheircompositions Pleaselistthreecategoriesandgivesomeexamplesofceramicsaccordingtheiratomicstructrualfeature Whatarepolymers Whatarecharacteristicsofpolymers Pleasegivesomeexamplesofpolymers 47 48 SiO2 approximately72 Na2OCaO Glass brittleness similarwithcrystallineceramic 49 Accordingtotheircompositions ceramicscanbedividedintotwocatogories Oneisoxideceramicssuchasaluminumoxide Al2O3 magnesiumoxide MgO andsilica SiO2 theotheroneisnonoxideceramics siliconnitrideisanimportantnonoxideceramic 50 accordingtotheiratomicstructualfeature therearethreetypesofceramicsascrystallineceramics noncrystallineceramicsandthethirdcategory glass ceramics Siliconnitrideisoneofcrystallineceramics glassisakindofnoncrystallineceramicsandglass ceramicsisarelativelyrecentmaterial thatis certainglasscompositions suchaslithiumaluminosilicates canbefullydevitifiedbyanappropriatethermaltreatment 51 Polymersarelong chainmoleculescomposedofmanymersbondtogether Polyethylene acrylicsandnylonarealltypicalpolymers Polymersarenobrittleness highstrengthalongit schainandlowstrengthbetweenit schains lightweight low cost lowermeltingpointandhigherchemicalreactivitycomparedwithceramics atlastpolymersareman madematerials 52 shell 53 wood 54 55 56 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 57 Combinationofindividualmaterialsfromthepreviouscategories Characteristics thebestofbothworldsItcarryalongthesuperiorpropertiesofeachcomponent producingaproductthatissuperiortoeitherofthecomponentsseparately 58 Example fiberglass wood concrete 59 60 s 61 SupplementaryintroductionSemiconductors Apieceofequipmentthatproducesapowerfulnarrowbeamoflightthatcanbeusedinmedicaloperations tocutmetals ortomakepatternsoflightforentertainment 1 arsenide 5B sEnaid 砷化物 Acompoundofarsenicwithamoreelectropositiveelement 2 laser 62 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 63 Semiconductorsarerelativelyinvisiblecomparedwithpolymers buthaveacomparablesocialimpact Semiconductorsarethebasisofmodernelectronics 64 65 Arelativelysmallgroupofelementsandcompoundshasanimportantelectricalproperty threesemiconductingelements Si silicon Ge germanium dVE 5meiniEm Sn tin compounds GaAsgallium 5 AliEm arsenide CdScadmiumsulfide 5kAdmiEm5sQlfaid ceramicscompound ZnOPrecisecontrolofchemicalpurityallowsprecisecontrolofelectronicproperties 66 Characteristics semiconduction inwhichtheyareneithergoodelectricalconductorsnorgoodelectricalinsulators 5insjuleitE instead theirabilitytoconductelectricityisintermediate 7intE5mi djEt 67 Atomic scale architectureCompositeDevitrified di 5vitrifai 使不透明DuctilityElectronicandmagneticmaterialFiberglassMaterialsselectionMicrocircuitry 5maIkrEJs kIt 电子 微电路Microscopic scalearchitectureRefractoryStructuralmaterial 68 Qustions 1 Pleasedefinecomposites andthendemonstratethecharacteristicsofgoodcompositesbysomeexamples 2 pleaseenumerate i5nju mEreit v 列举 semiconductingelementsandcompounds 69 Compositeismaterialcomposedofamicroscopic scalecombinationofindividualmaterialsfromthecategoriesofmetals ceramics andglasses andpolymer E g fiberglassisakindofcompositesystemcomposedofpolymericmatrixreinforcedwithglassfibers Characteristicoffiberglassprovidesthebestofbothworlds Itcarryalongthesuperiorpropertiesofeachcomponent producingaproductthatissuperiortoeitherofthecomponentsseparately Thehighstrengthofthesmall diameterglassfibersiscombinedwiththeductilityofthepolymermatrixtoproduceastrongmaterialcapableofwithstandingthenormalloadingrequiredofastructuralmaterial 70 Therearethreesemiconductingelements Si GeandSn fromcolumnIVAandaclusterofelementsoftheperiodictableimmediatelyadjacenttocolumnIVA whichformscompoundsthataresemiconducting Examplesincludegalliumarsenide GaAs whichisusedasahigh temperaturerectifier 5rektifaiE 整流器 andalasermaterial andcadmiumsulfide CdS whichisusedasarelativelylow costsolarcellforconversionofsolarenergytousefulelectricalenergy 71 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 72 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 73 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 74 Tounderstandthepropertiesofengineeringmaterialsitisnecessarytounderstandtheirstructure 75 Atomic scalearchitecture10000000times Microscopic scalearchitecture1000times 76 Example1 Al MgAlalloysareductileMgalloysarebrittle 77 AlstructurefollowsacubicpackingarrangementandMgahexagonalone 78 79 80 Example2 transparentceramicsTraditionalceramicscontainedasubstantialamountofresidualporosity Theporosityleadstolossofvisiblelighttransmission Onlyabout0 3 porositycancauseAl2O3tobetranslucent and3 porositycancausethematerialtobecompletelyopaque Theeliminationofporosity addingasmallamountofimpurity 81 Theeliminationofporosityresultedfromarelativelysimpleinventionthatinvolvedaddingasmallamountofimpurity 0 1wt MgO whichcausedthehigh temperaturedensificationprocessfortheAl2O3powdertogotocompletion 82 PorosmicrostructureinpolycrystallineAl2O3 83 Figure1polycrystallinefacetedsapphiresandrubies Figure3polisheddiscswithseveraldopants thickness 0 8mm 84 85 Thetwoexamplesjustcitedshowtypicalandimportantdemonstrationsofhowpropertiesofengineeringmaterialsfollowdirectlyfromstructure 86 Qustions 1 Aluminumandmagnesiumarebothmetal whyaluminumisrelativelyductilewhilemagnesiumisrelativelybrittle Pleaseexplainthedramaticeffectthatstructurehasonpropertiesontheatomicscale 2 whytraditionalceramicssuchasaluminumoxideareopaquewhereasrecentlyopticallytransparentaluminumoxideceramicsareproduced Whatarethedifferencesbetweentheirmicroscopic scalearchitectures 87 1 3Selectionofmaterials anyofagroupofverystronglightweight syntheticfibersusedinmakingradialtires bulletproofofvests etc 1 etc Latinthewrittenabbreviationforetcetera usedafteralisttoshowthattherearemanyothersimilarthingsorpeoplethatyoucouldhaveadded andsoforth andsoon andtheothers 2 ASTM AmericanSocietyforTestingandMaterials 3 aramid 88 Apolymercontainingrepeatedamidegroups asinvariouskindsofnylon 4 Aromatic 7ArEu5mAtik Of relatingto orcontainingoneormoresix carbonringscharacteristicofthebenzene 5benzi n ben5zi n seriesandrelatedorganicgroups 5 Polyamide 89 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 90 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 91 7 Theaddedcostoffabricatingthesemoresophisticatedmaterialsystemsisjustifiedonlyifaspecialadvantageresults fabricate 5fA