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word文檔可自由復(fù)制編輯ResearchprogressofcarbonfibercompositematerialAbstract:Basedontheintroductionofcarbonfiber,brieflydiscussesthestructure,characteristicsandclassificationofcarbonfiber,andemphaticallyintroducesthepropertiesofcarbonfibercompositematerials,classification,applicationandmoldingmethod,includinghandlay-upmolding,resintransfermolding,injectionmolding,Formingandpultrusionfiberwinding.Keywords:carbonfiber;compositematerial;classification;moldingIntroductionCarbonfiber(carbonfiber,referredtoasCF),isanewtypeoffibermaterialcontainingcarboncontentin95%above.Itnotonlyhastheintrinsiccharacteristicsofcarbonmaterials,aswellasprocessingtextilefiberissoft,isanewgenerationofreinforcedfiber.Withthetraditionalglassfiber(GF),Young'smodulusis3timesasmuch;itandtheKevlarfiber(KF-49),notonlytheyoung'smodulusisabout2times,butinsolubleinorganicsolvents,expansionofacid,alkali,corrosionresistance,riseabovethecommonherd.Carbonfiberisakindofhighperformancefiber,hashighspecificstrength,highspecificmodulus,hightemperatureresistance,chemicalcorrosionresistance,radiationresistance,fatigueresistance,creepresistance,conductive,heattransferandlowcoefficientofthermalexpansionandaseriesofexcellentpropertiesof[1].duetothematerialhashighstrength,highmodulus,hightemperatureresistance,fatigueresistance,conductivity,thermalconductivityandothercharacteristics,soitiswidelyusedincivilconstruction[2],aerospace,automotive,sportsandleisuregoods,energyandmedicalandhealthfields.Inaddition,carbonfiberhasbeenwidelyusedinelectroniccommunications,petroleumexploitation,infrastructureareassuchas[3],mainlyusedforthedischargeofshieldingmaterials[4],anti-staticmaterials,separationofuraniumcentrifugematerials,batteryelectrodes[5],alsohaveoutstandingperformanceinthebiochemicalprotective,ozoneremoval,foodetc.field.Thebearingloadofcarbonfibercanbeusedasastructuralmaterial,butalsoplayaroleasfunctionalmaterials.Asakindofhighperformancefiber,carbonfiberandcarbonmaterialshavebeenwidelyusedinmilitaryandcivilindustrialfields,fromaviation,aerospace,automotive,electronics,machinery,chemical,textileandothercivilindustrytosportsandleisureproductsetc..Therefore,thecarbonfiberisregardedasatypicalrepresentativeofnewindustrialmaterialsinthefieldoftheworld.1.Thestructure,characteristicsandclassificationofcarbonfiberCarbonfiberisakindofspecialfibercomposedofcarbon,thecarboncontentvarywiththetype,generallyinmorethan90%.Hissteelaccountedforlessthan1/4,evenlighterthanaluminum,morethan20timesthestrengthofiron.Comparedwithtitanium,steel,aluminumandothermetalmaterials,carbonfiberhashighstrength,highmodulus,lowdensity,linearexpansioncoefficientofsmall,inthephysicalproperties,canbecalledthekingofnewmaterials.Itisgenerallythesamecarbonmaterialhasthecharacteristics,suchashightemperatureresistance,frictionresistance,conductivity,thermalconductivityandcorrosionresistance,butaredifferentfromgeneralcarbonmaterial,itsappearancehasobviousanisotropy,soft,canbeprocessedintoavarietyoffabrics,alongthefiberaxisshowaveryhighstrength.[9]smallproportionofcarbonfiber,ithasahighspecificstrength.Therefore,thecarbonfibercanbe.[6]fieldusedinaircraftmanufacturing,militaryindustry,windpowerbladesandotherindustrialfields,suchasGOLFbatsportsleisureCarbonfiberstructuredependsonthestructureandthecarbonizationprocess,butnomatterwhatkindofmaterial,carbonfibercarbonatomsinaplanealwaysalongthefiberaxisparallelorientation.Foundbyx-rayandelectronmicroscopicstudyofthegraphitelatticestructure,therealstructureofcarbonfiberisnotideal,buttotheturbostraticstructure,asshowninFigure1-1.Abasicelementofthisstructureishexagonalcarbonlayerbylayercomposedoflattice,latticeplane.Intheplaneofthelayerofcarbonatomsinstrongcovalentbondconnected,thebondlengthis0.1421nm;intheplaneofthelayerareconnectedbyweakFanDehuaforces,layerspacingbetween0.336~0.344nm;fixedpositionofcarbonatomwithoutrulesbetweenlayerandlayer,thelayeredgeuneven.Inthebasisofcarbonatomsandtheinternalstructureofcompleteatomicleveledgeofgraphitelayersofdifferent.Thebasisofcarbonatomiclevelinternalgravityissymmetrical,bondenergyishigh,lowreactionactivityatthesurface;attheedgeofthecarbonatomforceasymmetry,withunpairedelectrons,activityisrelativelyhigh.[2]Fig.1-1carbonfiberStructureCarbonfibermainlyhavethefollowingcharacteristics:(1)smalldensity,lightweight,carbonfiberdensityis1.5-2g/cm3,whichinadditiontotheoriginalwirestructurerelated,mainlydependsonthecarbonizationtemperature.Afterhightemperature(3000℃)graphitization,densityofupto2.0g/cm3.(2)strength,highelasticmodulus,itsstrengthis4-5timeslargerthansteel,elasticrecoveryof100%;(3)asmallcoefficientofthermalexpansion,thermalconductivitydecreasedwithincreasingtemperature,resistancetocold,hot,evenfromthousandsofdegreesCelsiustemperaturesuddenlydroppedtonormaltemperaturewillnotburst;(4)thefrictioncoefficientissmall,andwithlubrication;(5)goodconductivity,25℃highmoduluscarbonfiberthantheresistanceof775Ω·cm,highstrengthcarbonfiberis1500Ω·cm;(6)hightemperatureandlowtemperatureisgood,no,notthesofteningmeltingat3000℃nonoxidizingatmosphere,atliquidnitrogentemperatureisstillverysoftalso,notbrittle;goodacidresistance,acidresistanceisinert,concentratedhydrochloricacid,phosphoricacid,sulfuricaciderosion.Inaddition,carbonfiberisalsoresistanttooil,antiradiation,antiradiation,absorptionoftoxicgasesandtheneutronanddecelerationfeatures.[7]Becauseoftherawmaterialanditspreparationmethod,carbonfiberscanbeclassifiedfromthefollowingtwoaspects:(1)Accordingtothemechanicalpropertiesofcarbonfiberscanbedividedintohighmodulus,highmodulusandhighstrengthandsuperhighstrength.(2)Accordingtothetypeofrawsilkcanbedividedintopolyacrylonitrilebasedcarbonfiber,cellulosebasedcarbonfibers,carbonfibers,rayonbasedcarbonfiber(FenQuanji)three.[8]Carbonfiberrawmaterialsmainlythroughpolymerization,spinning,afterpreoxidation,carbonizationandgraphitizationcanbeprepared.Polyacrylonitrilesolutionpolymerization,emulsionpolymerization,suspensionpolymerizationandbulkpolymerization,bywetspinningordryjetwetspinningofrawsilk.2.carbonfiberreinforcedcomposites2.1ThestructureandpropertiesofcarbonfiberreinforcedcompositematerialsFiberreinforcedcompositematerialismadeofcarbonfiberfabricreinforcedresincarbonorgraphite(includingLiQing)compositecarbonoftheformationofcarbonandchemicalvapordeposition,carboncarboncomposites.Itismadeofcarbonfiberorcarbonfiberfabricreinforcedwithresin,carbonorgraphiteasasubstrate.Thestrengthofthecompositeathightemperatures,hightemperaturestablemorphology,sublimationtemperaturehigh,ablationofdepression,withhighstrengthandhighrigidityisparalleltothedirectionofcrackpropagationcanbeenhanced,resistance,canshock,antiradiation.Characteristicsofcarboncompositeismainlymanifestedinthreeaspectsofmechanicalproperties,thermalphysicalpropertiesandthermalablationproperties.(1)andlowdensity(1.7g/cm3)inthestructureunderhightemperature,itisthelightestmaterial;hightemperaturestrength,in2200℃mayretainthestrengthatroomtemperature;havehigherfracturetoughness,fatigueresistanceandcreepresistance;andthetensilestrengthandelasticmodulusishigherthanthatofcarbonmaterials,fiberorientationsignificantlyaffectthestrengthofthematerial,thestresswhenthestress-straincurvepresents"fakeplasticeffect"thatislinearintheinitialloading,becamethebilinearrelation,afterunloadingreloading,curveislinearandcanachievetheloadleveloftheoriginal.(2)smallthermalexpansioncoefficient,heatcapacity,canstorealotofheat,lowthermalconductivity,thermalshockandthermalperformanceoffrictionandexcellent.(3)resistantpropertiesofablation,ablationperformanceinheateffect,becausethesurfaceofsolidmateriallosscausedbychemicalandmechanicalprocessofthephenomenon,throughtheablationsurfacematerialawayalotofheat,canpreventtheheatintothematerial,C-Cmaterialisakindofsublimation-radiationtypematerial.[10]2.2StudyprocessingmethodsandprocessingCarbonfiberreinforcedcompositematerialhasbeenclassifiedasthelong(continuous)andshortfiberstoprocessing,fromthetypical300~400meterstoseveralmillimetersintodifferentgrades.Inthepast10years,peoplehavebeenimprovedtodifferenttypesofcarbonfibercompositematerialpropertiesandprocessingmethods,fromtheshortfibermixtureinjectionprocessing,laminating,materialprocessingtothemoldingprocessofleachingfromthepre,andstrivetofindthebestprocessingasthematerialofthisexcellentperformanceMethod.2.2.1handlayupprocessThebiggestcharacteristicofhandlayupprocessismainlymanual,suitableformultivariety,smallbatchproduction,andisnotinfluencedbytheproductsizeandshapeconstraints.Butthismethodislowefficiency,poorworkingconditions,andlaborintensityisgreat;thequalityoftheproductsisnoteasytocontrol,poorstability,lowproductintensitythantheothermethods.AsshowninfigureFigure2-1handlayupprocessmap2.2.2resintransfermoldingRTMRTMisasuitablevariety,quantity,highqualitywithlowcosttechnologymaterials.Atpresent,inthedevelopedcountriesinthecompositesindustryalreadyby"production,consumption"into"personalized,high-grade,mediumyield"stage,resin,itisalsosuitablefor"personalized,high-grade,mediumyield"requirementsofthetransfermolding(RTM)process,thusobtainsthevigorousdevelopment.Asshowninfigure2-2:Figure2-2resintransfermoldingprocess2.2.3injectionmoldingprocessInjectionmoldingisthroughthesprayatomizationandshortcutfiberandresininjectiontothemoldsurface,therolling,curingmethodforcompositeparts.Itisfortheimprovementofhandlayupandcreateasemimechanizedmoldingtechnologydevelopment.Injectionmoldinghascertainrequirementsforrawmaterials.Suchasresinviscosityshouldbemoderate(0.3~0.8Pa?s),easytospray,removalofbubbles,wettingfiberandnoteasytodrainandwithoutelectrostaticetc..Productsoffibercontentcontrolin28%~33%,fiberlengthof25to50mm.Itsadvantageistheproductionefficiencythanhandpasteincreased2~4times,lowlaborintensity,realizebatchproductionwithlessequipmentinvestment,lowmaterialcost;productintegrity,theshapeandsizeofpartsisnotrestricted;adjustablewallthickness,ratiooffiberandresin.Themaindrawbackisthehighpollution,highresincontent,lowbearingcapacity.2.2.4injectionmoldingReactioninjectionmolding(RIM)andreinforcedreactioninjectionmolding(RRIMisthemaininjectionmoldingofthermoplasticplastics.Inrecentyearsthedevelopmentofnewinjectionmolding.ThebasicprincipleofRIMisthetworeactants(highlyreactiveliquidmonomeroroligomer)accuratemeasurement,highimpactbymixedfillingmold,mixtureinthemoldcavityrapidpolymerizationcuring.Itsoutstandingcharacteristicisthehighproductionefficiency,lowenergyconsumption.RRIMistheshortcutfiberorflakereinforcedmaterialenhancedRIM,whichisdevelopedonthebasisofRIM,addingreinforcingmaterialinthemonomer,reactionmonomerandreinforcingmaterialtothemoldcavitypreparationofcompositeproductsthroughthemixingheadinjection.2.2.5fiberwindingFilamentwindingisthefiberbundleimpregnatedresinor,inacertaintension,accordingtocertainrulesonamandrel,andthenintheproductmethodofheatingorroomtemperaturecuring.Themaincharacteristicsoffiberwinding,fibercankeepthecontinuity,partsaccordingtoproductlineforceaccordingtotheperformancerequirementsofdesigncanbeenhancedconfigurationstructurematerial,highefficiency,highproductstrength;continuous,mechanizedproduction,shortproductioncycle,lowlaborintensity;theproductdoesnotneedmechanicalprocessing,buttheequipmentcomplex,hightechnicaldifficulty,noteasytocontroltheprocessquality.2.2.6ThepultrusionPultrusionisaformingmethodforthecontinuousproductionoffixedprofiles.Asshowninthemainprocessissoakedwithresinfiberthroughacertaintypeoftheheatingofthediecontinuous,squeezeoutexcessresin,curinginthetractioncondition.Thebiggestcharacteristicofpultrudedcontinuousmolding,productlengthisnotlimited,themechanicalpropertiesespeciallythelongitudinaloutstandingmechanicalproperties,structureofhighefficiency,lowmanufacturingcost,highdegreeofautomation,productperformanceisstable,highproductionefficiency,highutilizationrateofrawmaterials,doesnotneedauxiliarymaterials.Itisanimportantmethodofhighperformanceandlowcostcompositemanufacturing,highfibervolumecontent.[10]asshowninfigure2-3:Figure2-3pultrusionprocess3.carbonfiberreinforcedcompositematerialsclassificationAlthoughthecarbonfibercanbeusedaloneplayacertainfunction,however,itisabrittlematerial,onlywillitandthematrixmaterialisfirmlycombinedtogether,canmakeuseoftheexcellentmechanicalproperties,andtobetterloadbearing.Therefore,thecarbonfiberismainlyinthecompositereinforced.Accordingtodifferentpurposesandcanchooseavarietyofmatrixmaterialandthecompositetocompositeeffectrequired.Carbonfibercanbeusedtoenhancetheresin,carbon,metalandceramic,andatpresent,themostwidelyusedatmostistheresinmatrixcompositematerials.3.1carbonfiberreinforcedceramicmatrixcompositesCeramichasexcellentcorrosionresistance,wearresistance,hightemperatureresistanceandchemicalstability,widelyusedinindustrialandcivilproducts.Itsweaknessisverysensitivetothecrack,airholeandinclusionsubtle.Carbonfiberreinforcedceramiccaneffectivelyimprovethetoughness,brittlefracturemorphologychangesofceramics,spreadrapidly,whilepreventingcracksintheceramicmatrixextension.Atpresent,morematuredomesticcarbonfiberreinforcedceramicmaterialsarecarbonfiberreinforcedsiliconcarbidematerials,becauseofitsexcellenthigh-temperaturemechanicalproperties,inhightemperatureservicewithouttheneedforadditionalinsulationmeasures,hasbeenwidelyusedinaeroengine,andrepeateduseofaerospaceandotherfields.Themainpreparationmethodsare:slurryinfiltrationandmixingprocess,chemicalsynthesisprocess(SOL-gelandpolymerprecursorprocess),meltinfiltrationprocess,insituchemicalreaction(CVD,CVIreactionsintering)etc..3.2carbon/CarbonCompositesCarbon/carboncompositematerialiscarbonfiberreinforcedcarbonmatrixcompositesforshort,isakindofadvancedcompositematerials.Itiscomposedofcarbonfiberorfabric,knittedfabricreinforcedcarbonmatrixcomposites.Carbon/carboncompositematerialmainlyconsistsofvariouskindsofcarbonfibers,carbon,resincarbonanddepositedcarbon.Thecompositematerialofentirelyartificialdesign,manufacturingoutofpurecarbonelementswithmanyexcellentproperties,buthastheadvantagesofhighstrength,highrigidity,dimensionalstability,oxidationresistanceandwearresistanceproperties,butalsohashigherfracturetoughnessandpseudoplastic.Especiallyintheconditionofhightemperature,highstrength,nomeltingdoesnotburn,onlyuniformablation.Thisisanymetalmaterialnottheirmatch.Itiswidelyappliedtothemissilewarhead,nozzleofsolidrocketengineandaircraftbrakediscsandotherhigh-techfields.Thepreparationprocessasshowninfigure3-1:3.3carbonfiberreinforcedmetalmatrixcompositesCarbonfiberreinforcedmetalmatrixcompositeswithcarbonfiberasreinforcedfibers,metalmatrixcompositematerial.Carbonfiberreinforcedmetalmatrixcompositescomparedwithmetalmaterial,hastheadvantagesofhighspecificstrengthandmodulus;comparedwithceramic,hightoughnessandimpactresistance,theuseofaluminummetalmatrix,magnesium,nickel,titaniumandtheiralloys,wherein,thecarbonfiberreinforcedaluminum,magnesiumcompositesmaturetechnology.Themaintechnicaldifficultiesinmanufacturingcarbonfiberreinforcedmetalmatrixcompositesissurfacecoatingofcarbonfiber,inordertopreventthedamageofcarbonfiberinthecompositeprocess,sothattheoverallpropertiesofthecompositesdecrease.Atpresent,inthepreparationofcarbonfiberreinforcedsurfacemetalmatrixcompositecarbonfibermodificationmainlybyvaporphasedepositionmethod,liquidsodium,butbecauseofitscomplexprocess,highcost,limitedtheapplicationofcarbonfiberreinforcedmetalmatrixcomposites.Themainpreparationmethodsare:solidphasemethod,liquidphasemethodandinsitucompositemethod.Solidphasemethodsmainlyincludepowdermetallurgy,solidhotpressing,hotisostaticpressingmethod;liquidmethodmainlyhasthevacuumpressureimpregnation,squeezecastingmethod;insitucompositemethodmainlyincludeseutecticalloydirectionalsolidification,directmetaloxidemethod,reactionformationmethod.3.4carbonfiberreinforcedresincompositeCarbonfiberreinforcedresinmatrixcomposites(CFRP)isoneofthemostadvancedcompositematerials.Ittakeslight,highstrength,hightemperatureresistance,corrosionresistance,excellentthermodynamicperformancewidelyusedasstructuralmaterialsandhightemperatureantiablationmaterials,otherfiberreinforcedcompositematerialsbytheincomparable.Carbonfiberreinforcedresinmatrixusedinresincompositematerialscanbedividedintotwocategories,onecategoryisathermosettingresin,anotherkindisthermoplasticresin.Thermosettingresinbyreactivelowmolecularweightprecollectiveorwithactivegroupsofhighmolecularweightpolymer;moldingprocess,crosslinking,polymerizationincuringagentorheateffect,theformationofinsolubleandinfusiblecrosslinkingtypestructure.Oftenusedincompositematerialswithepoxyresin,bismaleimideresin,polyimideresinandphenolicresin.Thethermoplasticresiniscomposedoflinearhighmolecularweightpolymer,undercertainconditions,dissolvedmelt,onlythephysicalchangesthatoccur.Commonlyusedpolyethylene,nylon,PTFEandpeeketc..Inthecarbonfiberreinforcedresinmatrixcomposites,carbonfiberreinforcedresinmatrixtotherole,andthecompositematerialmoldingforbearingforce,andthroughtheinterfaceloadtransferfromcarbonfiber,soitstechnicalperformance,carbonfibercompositematerialmoldingprocessandproductpricehasdirectinfluence.Compositecarbonfiberwillalsohaveanimpactontheperformanceofcompositematerials.[11]4.ApplicationofcarbonfiberandItsCompositesCarbonfiberanditscompositematerialhashighstrength,highmodulus,hightemperatureresistance,fatigueresistance,electricalconductivity,thermalconductivity,itiswidelyusedinthecivilconstruction,aerospace,automotive,sportsandleisuregoods,energyandmedicalandhealthfields.Inaddition,carbonfiberhasbeenwidelyusedinelectroniccommunications,petroleumexploitation,infrastructureandotherfields,mainlyusedforthedischargeofshieldingmaterials,anti-staticmaterials,separationofuraniumcentrifugematerials,batteryelectrodes,inbiochemicalprotective,exceptforozone,foodandotherfieldshaveacolorrepresentation.Compositematerialisformedbythecombinationofcarbonfiberandepoxyresininthefieldofaviation,duetoitssmallspecificgravity,goodrigidityandhighstrengthandbecomeakindofadvancedaerospacematerials.Becausethequalityofspacecraftreduces1kg.Itcanmaketherockettoreduce500kg.So,intheaerospaceindustrytoadopttheadvancedcompositematerials.Thereisaverticaltake-offandlandingaircraft,carbonfibercompositematerialsandthewholemachinequalityhaveaccountedfor1/4,accountingforthequalityof1/3.Accordingtoreports,thekeycomponentsof3rocketpropulsionAmericanshuttleandadvancedMXmissilelaunchtube,areusingadvancedcarbonfibercompositematerialmadeofcarbonfiberisakindofcarbonmaterial.Itisakindofstrengththansteel,aluminum,densityissmallthanthestainlesssteelisalsoresistanttocorrosion,hightemperatureresistance,heatresistantsteelandasconductivethancopper,thenewmaterialhasmanyvaluableelectrical,thermalandmechanicalproperties.Compositematerialsmadeofcarbonfiberandplasticsdonotonlytheplanelight,andlittlepowerconsumption.Largethrust,lownoise;carbonfiberelectroniccomputerdisk,canimprovethecomputerstoragecapacityandcomputingspeed;carbonfiberreinforcedplastictomakethesatelliteandtherocketandspacecraft,highmechanicalstrength,quality.Inthefieldofcivil,applicationofcarbonfiberreinforcedresinmatrixcompositematerialsisalsogrowing,suchasautomobileparts,windturb
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