材料科学概论.ppt

Introduction to Materials Science and EngineeringGuan Rui-fang1精选ppt2精选ppt材料与新技术革命材料与新技术革命3精选ppt4精选ppt5精选ppt6精选ppt7精选ppt材料与国防现代化材料与国防现代化8精选pptThis book is divided into four major sectionsI.The fundamentalsII.The structural materialsIII.The electronic and magnetic materialsIV.Materials in engineering designsciencematerialsengineering9精选pptNature of materials propertiesMicroscopic or submicroscopic structureEngineering design10精选pptChapter I Materials for Engineering1.1 Types of materials1.2 From structure to properties1.3 Selection of materials1.4 Materials science and engineering 11精选pptKey wordAlloy 5AlCi5AlCi Atomic-scale-architectureBrittle 5britl5britlCeramic si5rAmiksi5rAmikComposite 5kCmpEzit,-5kCmpEzit,-zaitzaitConcrete 5kCnkri:t5kCnkri:tConductorCrystalline 5kristElain5kristElain adj.Devitrified di:5vitrifaidi:5vitrifaiDuctility dQk5tilitidQk5tilitiElectronic and magnetic materialElement 5elimEnt5elimEntFiberglass 5faIbElB:s5faIbElB:s12精选pptGlassGlass-ceramicInsulatorMaterials science and engineeringMaterials selectionMetallicMicrocircuitry 5maIkrEJs:kIt5maIkrEJs:kItMicroscopic-scale architectureNoncrystallineNonmetallic 5nCnmi5tAlik5nCnmi5tAlikKey word13精选pptOxidePeriodicpiEri5CdikpiEri5Cdik tablePlasticPolyethylene 7pCli5eWili:n7pCli5eWili:nPolymerPropertyRefractorySemiconductorSilica硅石，硅石，SiO2Silicate硅酸盐硅酸盐Silicon硅元素硅元素SteelStructural materialwoodKey word14精选ppt1.1 Types of materials a.Metals metallic bond b.Ceramics(glass)ionic aI5RnIkaI5RnIk and covalent kEu5veilEntkEu5veilEnt bond c.Polymers covalent and Van der waals bond d.Composites e.semiconductorsWhat materials are available to me?Five categories15精选ppt16精选pptAMetals超塑性的,超塑性材料(制)的1.i.e.Latin，the written abbreviation for id est,也就是，即。读作：that is2.state-of-the-art技术发展水平，现代化的。3.superplastic.17精选pptCharacteristics(metallic 金属的，金属性的金属的，金属性的)It is strong and can be readily formed into practical shapes.Ductile 5dQktail5dQktail permanent deformabilitymetallic lusterelectric conductor Metals have no brittleness and are safe for many applications.Structural steel 18精选pptGasket5Askit垫圈,衬垫springwireValvevAlv19精选ppt20精选ppt21精选ppt22精选pptB Ceramics si5rAmiksAhomogeneousmixtureoftwoormoresubstances,whichmaybesolids,liquids,gases,oracombinationofthese.1.Refractory ri5frAktEriDifficulttomeltorwork;resistanttoheat.2.fracture toughness断裂韧度3.crystalline5kristElainBeing,relatingto,orcomposedofcrystalorcrystals.4.Devitrify di:5vitrifaiTocause(aglassymaterial)tobecomecrystallineandbrittle.5.solution23精选pptThe ceramics is derived from Greek word “keramic”which means an art of potter.Include :glass ;enamels i5nAmEli5nAmEl;refractories;cements;limes;plasters(plaster of Paris);cermets5sE:met5sE:met金属陶瓷金属陶瓷,含陶合金含陶合金;electronic ceramics;high and low tension electrical insulators;structural clay products;nuclear ceramics;whitewares;abrasives E5breisivE5breisiv.24精选pptThe Different Colors of Corundum kE5rQndEmkE5rQndEmkE5rQndEmkE5rQndEm RubySapphire5sAfaiE5sAfaiE25精选ppt Why shouldnt Al2O3 be chosen for certain applications where metallic aluminum has been used?1、Al2O3 have two advantages:first,chemicallystable;Aloxidizedsecond,highermeltingpoint(20200C)Al(6600C)refractoryuseinindustrialfurnaceconstruction26精选pptQuestions1.What materials are available to you in this book?2.What fundamental characteristics metals have?3.Please shade metallic elements in periodic table and give some examples of alloys.4.Please list two principal advantages of Al2O3 relative to metallic Al.5.Whats the most limiting property of ceramics.27精选pptThemostlimitingpropertyofceramicsbrittlenessRecentdevelopmentinceramictechnologyareexpandingtheutilityofceramicsforstructuralapplicationnotbyeliminatingtheirinherentbrittleness,butbyincreasingtheirstrengthtosufficientlyhighlevels(greaterthan700MPa)andincreasingtheirresistancetofracture.28精选ppt2、Al2O3MgOSiO2Si3N4Atleastonemetallicelement+oneoffivenonmetalelement(C,N,O,PandS)Carbide 5kB:baidNitride 5naitraidOxide5CksaidPhosphide 5fCsfaidSulphide.5sQlfaidOxideceramicsNonoxideceramics29精选ppt3、Onemetallicelementplusoneoffivenonmetallicelements(C,N,O,P,orS)30精选ppt4、Characteristics:refractoryhighhardnesshighstrengthhighbrittleness31精选ppt32精选ppt33精选pptThe similar structural feature of metals and ceramics:Crystalline:their constituent atoms are stacked together in a regular,repeating pattern.The distinction:ceramics can be made in a noncrystalline form.skI5mAtIk34精选pptSiO2(approximately 72%)Na2O CaOGlass:brittleness similar with crystalline ceramictransmit visible lightchemical inertness glasses are important engineering materials35精选pptGlass-ceramics is a third categoryLithium aluminosilicatesCertain glass compositions can be fully devitified by an appropriate thermal treatmentlow-thermal expansion coefficientscomplex formshigh mechanical strengthVitreous 5vItrIEsglassy stateSubsequentcrystallization36精选ppt37精选ppt38精选pptC Polymers(plastics)Exempli gratia.For example.1.ethylene A colorless,flammable gas,C2H4,derived from natural gas and petroleum and used as a source of many organic compounds,in welding 5weldiN焊接and cutting metals,and as an anesthetic 7Anis5Wetik麻醉剂.2.polyethylene A polymerized ethylene resin,used especially for containers,kitchenware,and tubing,or in the form of films and sheets for packaging.3.e.g.39精选ppt Any of numerous organic compounds,such as benzene and methane,that contain only carbon and hydrogen.4.Acrylics E5kriliks丙烯酸树脂5.Nylon 5nailEn Any of a family of high-strength,resilient synthetic polymers,the molecules of which contain the recurring amide group CONH.6.Hydrocarbon40精选ppt These man-made materials are a branch of organic chemistry.41精选ppt42精选ppt1.Poly+mer:mer in a polymer is a single hydrocarbon molecule such as ethylene(C2H4).long chain olecules:Polymers are long-chain molecules composed of many mers bond together.43精选ppt44精选ppt 1)no brittleness2.Characteristics:2)lower melting point3)high strength along its chain and low strength between its chains 4)lightweight low-cost5)higher chemical reactivity6)Man-made materials45精选pptSubstitution for traditional structural metals46精选pptQustions1.please illustrate two type of elements that composed ceramic compounds in periodic table.2.What are the major compositions of glass?why glasses are important engineering materials?3.Please list two categories and give some examples of ceramics according their compositions.4.Please list three categories and give some examples of ceramics according their atomic structrual feature.5.What are polymers?What are characteristics of polymers?Please give some examples of polymers.47精选ppt48精选pptSiO2(approximately 72%)Na2O CaOGlass:brittleness similar with crystalline ceramictransmit visible lightchemical inertness glasses are important engineering materials49精选pptAccording to their compositions,ceramics can be divided into two catogories.One is oxide ceramics such as aluminum oxide(Al2O3),magnesium oxide(MgO),and silica(SiO2),the other one is nonoxide ceramics,silicon nitride is an important nonoxide ceramic.50精选pptaccording to their atomic structual feature,there are three types of ceramics as crystalline ceramics,noncrystalline ceramics and the third category,glass-ceramics.Silicon nitride is one of crystalline ceramics,glass is a kind of noncrystalline ceramics and glass-ceramics is a relatively recent material,that is,certain glass compositions(such as lithium aluminosilicates)can be fully devitified by an appropriate thermal treatment.51精选ppt Polymers are long-chain molecules composed of many mers bond together.Polyethylene,acrylics and nylon are all typical polymers.Polymers are no brittleness,high strength along its chain and low strength between its chains,lightweight,low-cost,lower melting point and higher chemical reactivity compared with ceramics,at last polymers are man-made materials.52精选pptshell53精选pptwood54精选ppt55精选ppt56精选pptD Composite(fiber reinforce plastics)Possessing hereditaryhI5redItErI rank in a political system or social class derived from a feudalistic 9fjU:dElIstIk stage of a countrys development.Inactive or inert.1.Albeit C:l5bi:It page 12,line 5Even though;although;notwithstanding.2.Noble page 12,para.2,line 257精选pptCombination of individual materials from the previous categories.Characteristics:the best of both worlds It carry along the superior properties of each component,producing a product that is superior to either of the components separately.58精选pptExample:fiberglass,wood,concrete.59精选ppt60精选ppts61精选ppt Supplementary introduction Semiconductors A piece of equipment that produces a powerful narrow beam of light that can be used in medical operations,to cut metals,or to make patterns of light for entertainment.1.arsenide 5B:sEnaid砷化物 A compound of arsenic with a more electropositive element.2.laser62精选pptSophisticated page 13，line 6 from below sE5fistikeitid adj.1.诡辩的,久经世故的2.Very complex or complicated:非常复杂精密或尖端的最新最尖端的技术 the latest and most sophisticated technology.63精选ppt Semiconductors are relatively invisible compared with polymers,but have a comparable social impact.Semiconductors are the basis of modern electronics.64精选ppt65精选pptA relatively small group of elements and compounds has an important electrical property。three semiconducting elements (Si(silicon),Ge(germanium dVE:5meiniEmdVE:5meiniEm),Sn(tin).compounds:GaAs gallium5AliEm5AliEm arsenide,CdS cadmiumsulfide 5kAdmiEm5kAdmiEm 5sQlfaid5sQlfaid ceramics compound:ZnO Precise control of chemical purity allows precise control of electronic properties.66精选pptCharacteristics:semiconduction,in which they are neither good electrical conductors nor good electrical insulators 5insjuleitE5insjuleitE,instead,their ability to conduct electricity is intermediate 7intE5mi:djEt7intE5mi:djEt.67精选pptAtomic-scale-architectureCompositeDevitrifieddi:5vitrifaidi:5vitrifai 使不透明使不透明DuctilityElectronic and magnetic materialFiberglassMaterials selectionMicrocircuitry 5maIkrEJs:kIt5maIkrEJs:kIt电子电子微电路微电路Microscopic-scale architectureRefractoryStructural material68精选pptQustions1、Please define composites,and then demonstrate the characteristics of good composites by some examples.2、please enumerate(i5nju:mEreit v.列举)semiconducting elements and compounds.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ppt1.2 From structure to properties The unit of luminous flux flQks流量,通量 in the International System,equal to the amount of light given out through a solid angle by a source of one candela kAn5di:lE intensity radiating equally in all directions.1.hexagonal heksAEnElHavingsixsides.2.lumen5lju: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n.等价物,相等物Avenue 5Avinju:n.林荫道,大街,方法,途径,路Refraction ri5frAkFEnn.折光,折射Determination of the refractive characteristics of the eye.屈光度测定：对眼睛折射特性的测定73精选pptTranslucent trAnz5lju:sntadj.半透明的,透明的Opaque Eu5peikn.不透明物adj.不透明的,不传热的,迟钝的Transparent trAns5pZErEntadj.透明的,显然的,明晰的Densification 7densifi5keiFEn致密化74精选ppt To understand the properties of engineering materials it is necessary to understand their structure.75精选pptAtomic-scale architecture10000000 timesMicroscopic-scale architecture1000times76精选pptExample 1:Al,Mg Al alloys are ductile Mg alloys are brittle77精选ppt Al structure follows a cubic packing arrangement and Mg a hexagonal one.78精选ppt79精选ppt80精选pptExample 2:transparent ceramicsTraditional ceramics contained a substantial amount of residual porosity.The porosity leads to loss of visible light transmission.Only about 0.3%porosity can cause Al2O3 to be translucent,and 3%porosity can cause the material to be completely opaque.The elimination of porosity:adding a small amount of impurity.81精选pptTheeliminationofporosityresultedfromarelativelysimpleinventionthatinvolvedaddingasmallamountofimpurity(0.1wt%MgO),whichcausedthehigh-temperaturedensificationprocessfortheAl2O3powdertogotocompletion.82精选pptPoros microstructure in polycrystalline Al2O383精选pptFigure 1polycrystalline faceted sapphires and rubiesFigure3polisheddiscswithseveraldopants(thickness:0.8mm)84精选ppt85精选pptThe two examples just cited show typical and important demonstrations of how properties of engineering materials follow directly from structure.86精选pptQustions1.Aluminumandmagnesiumarebothmetal,whyaluminumisrelativelyductilewhilemagnesiumisrelativelybrittle?Pleaseexplainthedramaticeffectthatstructurehasonpropertiesontheatomicscale.2.whytraditionalceramicssuchasaluminumoxideareopaquewhereasrecentlyopticallytransparentaluminumoxideceramicsareproduced?Whatarethedifferencesbetweentheirmicroscopic-scalearchitectures?87精选ppt1.3 Selection of materials anyofagroupofverystronglightweight,syntheticfibersusedinmakingradialtires,bulletproofofvests,etc.1.etc.Latinthewrittenabbreviationforetcetera,usedafteralisttoshowthattherearemanyothersimilarthingsorpeoplethatyoucouldhaveadded.andsoforth,andsoon,andtheothers2.ASTMAmericanSocietyforTestingandMaterials.3.aramid88精选ppt Apolymercontainingrepeatedamidegroups,asinvariouskindsofnylon.4.Aromatic 7ArEu5mAtikOf,relatingto,orcontainingoneormoresix-carbonringscharacteristicofthebenzene5benzi:n,ben5zi:nseriesandrelatedorganicgroups.5.Polyamide89精选pptAppreciationE7pri:Fi5eiFEnn.Ajudgmentoropinion,especiallyafavorableone。评价：判断或意见，尤指有益的。2.Materialsselectionisthefinal,practicaldecisionintheengineeringdesignprocessandcandeterminethatdesignsultimatesuccessorfailure.3.solid-stateadj.使用电晶体的,不用真空管的4.indefinitein5definitadj.不确定的,语不定的(indefinitearticle)90精选ppt5.althoughsomestructuralceramicscanwithstandtheanticipatedserviceload,serviceload负载6.criterionkrai5tiEriEnn.(批评判断的)标准,准据,规范critical5kritikEladj.评论的,鉴定的,批评的,危急的,临界的91精选ppt7.Theaddedcostoffabricatingthesemoresophisticatedmaterialsystemsisjustifiedonlyifaspecialadvantageresults.fabricate5fAbrikeitvt.制作,构成,捏造,伪造,虚构JustifyTodemonstrateorprovetobejust,right,orvalid:论证或证明正当、正确或有效8.optimal5CptimEladj.最佳的,最理想的9.propertycomparisonkEm5pArisn10.junction5dVQNkFEnn.连接,接合,交叉点,汇合处92精选ppt10.spherical5sferikEladj.球的,球形的;cylindricalsI5lIndrIk(E)l圆柱的11.integral5intirEladj.Essentialornecessaryforcompleteness;constituent:必须的：构成整体所必须的；应有的93精选ppt12.Inthepastquartercentury,thetermthatha