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2007-2008学年第一学期末考试试题(A卷)课程名称:FUNDAMENTALSOFMATERIALSSCIENCEANDENGINEERING一、填空题(20分)[每空0.5分]1ThedisciplineofmaterialsscienceinvolvesIncontrast,materialsengineeringis.2金属材料的晶体结构主要包括:,,,.3物质中原子之间相互作用起源于原子核和电子间交互作用,根据电子围绕原子的分布方式,可以将这些作用力分为:,,,,.4高分子材料的基本结构包括:,,,.5Formingtechniquesofmetallicmaterialscommoninclude,,,and,.6Hardnessofmaterialsismeasuredaccordingthesemethods,,,.7POLYMERADDITIVESappliedinpolymermaterialscommonincludes,,,,and,.8根据材料磁化率,可以把材料的磁性大致分为五类,,,,.10Threedifferentformingmethodsareusedtofabricateglassproducts:,,and.11自由基聚合方法是指,聚合过程包括三步,,.12FORMINGTECHNIQUESFORPLASTICSincludes:,,and.二、问答题(40分)[每题8分]1Givetheelectronconfigurationsforthefollowingions:Fe2+,Cu+,Br-andS-2.2什么叫复合材料?复合材料的优点有哪些?3什么叫导电率?导电的机理是什么?聚合物导电率为什么比较低?4金属材料成型方法选择主要依赖于什么因素?试述聚合物成型加工特点与优势?5Brieflycitethemaindifferencesbetweenionic,covalent,andmetallicbonding?三、计算题(40分)[每题10分]1Thenumber-averagedegreeofpolymerizationofapolypropyleneis6789,Computethenumber-averagemolecularweight?2ZirconiumhasanHCPcrystalstructureandadensityof6.51g/cm3.Whatisthevolumeofitsunitcellincubicmeters?3Ann-typesemiconductorisknowntohaveanelectronconcentrationof3×1018m-3.iftheelectrondriftvelocityis100m/sinanelectricfieldof500V/m,calculatetheconductivityofthismaterial.4Themagnetizationwithinabarofsomemetalalloyis3.2×105A/matanHfieldof50A/m.Computethefollowing:(a)Themagneticsusceptibility.(b)Thepermeability.A卷答案一、填空题(20分)[每空0.5分]1investigatingtherelationshipsthatexistbetweenthestructuresandpropertiesofmaterials.Onthebasisofthesestructure–propertycorrelations,designingorengineeringthestructureofamaterialtoproduceapredeterminedsetofproperties.2体心立方(body-centeredcubic)、面心立方(face-centeredcubic)、密排六方(hexagonalclose-packed)。3离子键(ionicbond)、共价键(covalentbond)、金属键(metallicbond)、分子间作用力(vanderwaal)和氢键(hydrogenbond)。4线形结构(linear),支链结构(branched),交联结构(crosslink),网状结构(network)。5forging,rolling,extrusion,anddrawing。6ROCKWELL,BRINELL,VICKERS7fillermaterials(填充物),plasticizers(增塑剂),stabilizers(稳定剂),colorants(着色剂),andflameretardants(阻燃剂)8铁磁性(ferromagnetism),亚铁磁性(ferrimagnetism),顺磁性(paramagnetism),反铁磁性(diamagnetism)和抗铁磁性(antiferromagnetism)。9pressing,blowing,anddrawing10链引发(initiation),链增长(propagation)和链终止(termination)。11compression(模压),blow(吹塑),andinjectionmolding(注射).二、问答题(40分)[每题8分]1Solution:Fe2+:1s2s2p3s3p63d6-------2Cu+:1s2s2p3s3p63d10--------2Br-:1s2s2p3s3p63d104s24p6------2S-2:1s2s2p3s3p6------------------------22Solution:Acomposite,inthepresentcontext,isamultiphasematerialthatisartificiallymade,asopposedtoonethatoccursorformsnaturally.Inaddition,theconstituentphasesmustbechemicallydissimilarandseparatedbyadistinctinterface(2分).discussed;theseincludemultiphasemetalalloys,ceramics,andpolymers(1分).(1)Mostcompositeshavebeencreatedtoimprovecombinationsofmechanicalcharacteristicssuchasstiffness,toughness,andambientandhigh-temperaturestrength(1分)(2)example,aircraftengineersareincreasinglysearchingforstructuralmaterialsthathavelowdensities(1分)(3)betterpropertycombinationsarefashionedbythejudiciouscombinationoftwoormoredistinctmaterialssuchasoptical,electricalandmagneticmaterialsandsoon(2分)(4)Costofsomematerialsmaybereducedbyaddingfillermaterials(1分)复合材料是有高分子、无机非金属或金属等多相材料通过人工组合而成的新型材料(2分),其基本是有连续相与分散相组成(1分)。复合材料的优点:1.提高力学性能(1分)2.降低材料的密度(1分)3.获得可用的功能性材料,如耐高温,光电磁性材料(2分)4.降低成本(1分)3Solution:Sometimes,electricalconductivity_isusedtospecifytheelectricalcharacterofamaterial(1分).Itissimplythereciprocaloftheresistivity,andisindicativeoftheeasewithwhichamaterialiscapableofconductinganelectriccurrent(2分).Withinmostsolidmaterialsacurrentarisesfromtheflowofelectrons,whichistermedelectronicconduction(2分).Inaddition,forionicmaterialsanetmotionofchargedionsispossiblethatproducesacurrent;suchistermedionicconduction(1分).Mostpolymericmaterialsarepoorconductorsofelectricitybecauseoftheunavailabilityoflargenumbersoffreeelectronstoparticipateintheconductionprocess(1分).Themechanismofelectricalconductioninthesematerialsisnotwellunderstood,butitisfeltthatconductioninpolymersofhighpurityiselectronic(1分).电导率是衡量材料电导能力的表观物理量(1分),它定义为单位电位下流过的每立方厘米材料的电流I(A)(2分)。材料导电的原因是因为材料内部有可以移动的带电载流子(1分),因而材料的导电率大小是有载流子密度与载流子迁移率决定(1分),载流子可以是电子,也可以是正负离子(1分)。聚合物的结构特点决定了,纯聚合物内部没有可以自由移动的电子,也不具有可以移动的离子(1分),另外载流电子也难以在聚合物链之间移动,所以大多数聚合物导电率是比较低的(1分)。4要知识点:Themethodschosendependonseveralfactors;themostimportantarethepropertiesofthemetal(1分),thesizeandshapeofthefinishedpiece(1分),and,ofcourse,cost(1分).Quiteavarietyofdifferenttechniquesareemployedintheformingofpolymericmaterials.Fabricationofpolymericmaterialsnormallyoccursatelevatedtemperaturesandoftenbytheapplicationofpressure(1分).Moldingisthemostcommonmethodforformingplasticpolymers.Theseveralmoldingtechniquesusedincludecompression,transfer,blow,injection,andextrusionmolding(2分).Foreach,afinelypelletizedorgranulizedplasticisforced,atanelevatedtemperatureandbypressure,toflowinto,fill,andassumetheshapeofamoldcavity(2分).主要依赖于以下几个因素:1.金属的延展性(1分)2.金属制品的尺寸与形状(1分)3.成本(1分)聚合物成型是将各种形态的物料制成所需要形状制件的过程,成型方法很多,不仅具有铸造性,可焊性与切削加工性,还具有挤压,注射,压延,压制,中空吹塑,纺丝成型等方法。聚合物加工特性(2分)聚合物材料的熔融特性,聚合物材料大多数成型操作有热软化或熔融的聚合物的流
本文标题:材料学院专业外语试题
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