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1、为了适应公司新战略的发展,保障停车场安保新项目的正常、顺利开展,特制定安保从业人员的业务技能及个人素质的培训计划北京化工大学,材料导论,名词解释Module77-1Understandthefollowingterms:(a)composites;(b)nanocomposites;(纳米复合材料)(c)environmentalcomposites.(a)ausefulcomplexsolidmaterialcomposedoftwoormorematerialsthatarecombinedonamacroscopicscalebyphysicalmeansanddonotlosethei
2、ridentity.(b)anewsubset(子集)ofCMC,MMCorPMC,arecompositeswithasubstratethatisreinforcedwithnanometersizeparticlesthatenhancethesubstratesphysicalproperties.(c)acompositeconsistingof80%advancedpolymerand20%aluminum,developedforautomotiveapplication,andeasilyrecycledandaremadeusinglowenergyandacleanmanu
3、facturingsystem.7-5WhatdotheabbreviationsCMC,PMCandMMCstandfor,respectively?MMC:Metallicmatrixcomposites金属基复合材料PMC:Polymermatrixcomposites聚合物基复合材料CMC:Ceramicmatrixcomposites陶瓷基复合材料7-6Definethefollowingterms:(a)fiber-reinforcedcomposite;(b)fiber;(c)whisker;(d)continuousfiber(连续纤维);(e)discontinuousfib
4、er;(f)criticallengthofafiber(a)amaterialssystemmadeprimarilyofvaryingamountsofaparticularfiberreinforcementembeddedinaprotectivematerialcalledamatrix;acouplingagentisappliedtothefibertoimprovetheadhesionofthefibertothematrixmaterial.(b)thebasicindividualfilament(个别纤维)ofrawmaterialfromwhichthreadsorf
5、abrics(线程或面料)aremade.(c)areformedfromextremelythinsinglecrystals(单晶)ofhighperfection(完善)withalargelength-to-diameterratioforreinforcingcompositematerials.(d)areessentiallyinfiniteinlengthandextendcontinuouslythroughoutthematrixinacompositematerial.(e)arenotlessthan3mminlengthandtendtoorientthemselve
6、sinthedirectionofresinflowasacompositematerialisprocessed.(f)Thelengthlimitforafibertohaveaload-carryingandreinforcingabilities(P332)7-8Listthefunctionsofamatrixandacouplingagentinacomposite.Thefunctionsofamatrixaretosupportandprotectthefibers,theprincipalload-carryingagent,andtoprovideameansofdistr
7、ibutingtheloadamongandbetweenthefiberswithoutitselffracturing.基体未破坏可分散均匀受力Acouplingagentprovidesaflexiblelayerattheinterfacebetweenfiberandmatrixthatwillimprovetheiradhesionandreducethenumberofvoidstrappedinthematerial.7-12Whenspeakingofinterfaceandinterphase,whichtermrepresentsthelargerareaorvolume
8、inacompositematerial?Recallthedifferencebetweenthetwotermsinterfaceandinterphase.Interphase界面相Interfaceisasurfacethatformsacommonareaorboundarysimilarinmanyrespectstograinboundariesbetweenanytwoconstituents(成分)inamonolithic(单片)material.Interphasesistheregionformedbetweentwointerfaces.Itisthereforead
9、istinctphaseinitselfwithitsownidentity(特性),formingaregioncontiguoustotwophases.7-13Sketchatypicalfiber-reinforcedcompositeandlabelthefollowing:matrix,reinforcingfiber,interface,Afiber-reinforcedcompositeisamaterialssystemmadeprimarilyofvaryingamountsofaparticularfiberreinforcementembeddedinaprotecti
10、vematerialcalledamatrix,acouplingagentisappliedtothefibertoimprovetheadhesionofthefibertothematrixmaterial.7-14Understandthedefinitionsoftheterms:(a)preimpregnation预浸渍;(b)prepreg预浸料;(c)preforms;(d)lamina;(e)laminate;(f)bulkmoldingcompound(BMCs)块状模塑料;(g)sheetmoldingcompounds(SMCs).(a)Fibercanbesatura
11、tedwithresinousmaterialthroughaprocesscalledpreimpregnation;(b)Thepreimpregnatedfibersarecalledprepregs;(c)Preformsarecustom-shaped定制成型,resin-bondedmats树脂结合剂垫forreinforcementofmoldedpartswithcomplexshapes.Inotherwords,apreformisabundle纤维束offibershavingthedesiredvolumeandarchitecture量和结构tofillamoldca
12、vity模具型腔foraone-shotmolding注射成型;(d)aflatarrangementofunidirectionalfibersorwovenfibersinamatrix平面布置的单向纤维或无纺布纤维基体;(e)astackoflaminawithvariousorientationsinthelamina;(f)apremixedmaterialofshortfiberspreimpregnatedwithresinandvariousadditives预混材料的短纤维预浸树脂及各种添加剂(g)sheetmoldingcompoundsareimpregnated,con
13、tinuoussheetsofcompositematerial.片状模塑料浸渍,复合材料的连续的片7-16Nametwotypesofglassfiber.Comparethemintermsoftheircompositions,propertiesandapplications.E-glass无碱玻璃纤维S-glass高强玻璃纤维E-glassiscomposedof55%silica,20%calciumoxide,15%aluminumoxide,and10%boronoxide.Itisthestandardgradeofglassusedinfiberglassandhasate
14、nsilestrengthofaboutGpaandhighresistivity.Fiberdiametersrangebetween3and20的二氧化硅,氧化钙20,15的三氧化二铝,10氧化硼无碱玻璃纤维组成。它是在玻璃纤维用玻璃的标准等级,并拥有约GPa和高电阻率的拉伸强度。纤维直径介于3至20微米S-glasswasdevelopedforhigh-tensile-strengthapplicationsintheaerospaceindustry.Itisaboutone-thirdstrongerthanE-glassandiscomposedof65%silicondioxi
15、de,25%aluminumoxide,and10%magnesiumoxide.拉伸强度高,在航空航天工业应用开发的S-玻璃。这是约三分之一比E玻璃和二氧化硅65,25的三氧化二铝,氧化镁10组成。7-17Whatisthestructureofaboronfiber?Whatistheproblemwhenboronfibersareusedasreinforcementinanaluminummatrix?Listoneapproachtoovercomethisproblem.课件Problemswithchemicalreactionsbetweenboronandothermeta
16、lscontinuetobeasourceofconcerntomaterialstechnologists.OneapproachtothisproblemwasthecoatingoftheBORSICfiberwithsiliconcarbide,whichprovidesafiberthatismorecompatiblewithmetal-matrixmaterials,particularlyathighoperatingtemperatures.7-18Comparecarbonandgraphitefibersintermsofmodulus,carboncontentandpyrolyzingtemperature.Whichfibermaterialha