cc復(fù)合材料微觀結(jié)構(gòu)對其制動摩擦磨損性能的影響

摘要：C/C復(fù)合材料是一種新型的高性能材料，在高溫、高強(qiáng)

度、高剛度等方面表現(xiàn)出優(yōu)異的性能。本文研究了C/C復(fù)合

材料的微觀結(jié)構(gòu)對其制動摩擦磨損性能的影響。通過對材料的

纖維取向、纖維長度、纖維分布等微觀結(jié)構(gòu)因素進(jìn)行改變，研

究了其對制動摩擦磨損性能的影響。研究結(jié)果表明，C/C復(fù)合

材料的微觀結(jié)構(gòu)對其制動摩擦磨損性能具有顯著影響，纖維取

向越近似于切向，摩擦磨損性能越好；纖維長度過長或過短時(shí),

制動摩擦磨損性能均會受到影響；均勻分布的纖維能夠提高材

料的制動摩擦磨損性能。

關(guān)鍵詞：C/C復(fù)合材料；微觀結(jié)構(gòu)；制動摩擦磨損性能；纖維

取向；纖維長度；纖維分布

Introduction

C/Ccompositematerialisanewtypeofhigh-performance

material,whichhasexcellentpropertiessuchashightemperature

resistance,highstrength,andhighstiffness.Ithasbeenwidely

usedinthefieldsofaerospace,automotive,andmilitaryindustries.

ThefrictionandwearbehaviorofC/Ccompositematerialsisvery

importantfortheirpracticalapplications,especiallyinbraking

systems.Inthisstudy,theinfluenceofthemicrostructureofC/C

compositematerialonitsbrakingfrictionandwearbehaviorwas

investigated.

ExperimentalProcedures

C/Ccompositematerialswithdifferentmicrostructureswere

preparedbychangingthefiberorientation,fiberlength,andfiber

distribution.Thefibersusedwerecarbonfiberswithadiameterof

7|imandalengthof1-3mm.Thematrixusedwaspitch-based

carbon.Thefiberorientationwascontrolledbychangingtheangle

betweenthefibersandthepressingdirection.Thefiberlengthwas

controlledbycuttingthefiberstodifferentlengths.Thefiber

distributionwascontrolledbymixingthefiberswiththematrix

usingdifferentmethods.

Thefrictionandwearbehaviorofthematerialsweretestedusinga

pin-on-disctester.Thetestconditionswere:slidingspeedof1m/s,

slidingdistanceof1000m,andnormalloadof10N.Theworn

surfaceswereobservedusingascanningelectronniicroscope

(SEM)toanalyzethewearmechanism.

ResultsandDiscussions

Theinfluenceoffiberorientationonthebrakingfrictionandwear

behaviorofC/Ccompositematerialswasinvestigatedbychanging

theanglebetweenthefibersandthepressingdirection.Theresults

showedthatwhenthefiberorientationwasclosetotangential

direction,thebrakingfrictionandwearbehaviorwasthebest.The

reasonforthisisthatwhenthefibersareorientedtangentially,the

contactareabetweenthefibersandthefrictionsurfaceisthe

largest,whichleadstoahigherfrictionforceandbetterwear

resistance.

Theinfluenceoffiberlengthonthebrakingfrictionandwear

behaviorofC/Ccompositematerialswasalsoinvestigated.When

thefiberlengthwastoolongortooshort,thebrakingfrictionand

wearbehaviorwasaffected.Whenthefiberlengthwastoolong,it

wasdifficulttoobtainahomogeneousmixtureofthefibersandthe

matrix,whichledtoadecreaseinthemechanicalpropertiesofthe

material.Whenthefiberlengthwastooshort,thefibercontentin

thematerialwastoolow,whichledtoadecreaseinthemechanical

propertiesandwearresistance.

Theinfluenceoffiberdistributiononthebrakingfrictionandwear

behaviorofC/Ccompositematerialswasinvestigatedbychanging

themixingmethod.Theresultsshowedthatwhenthefiberswere

uniformlydistributedinthematrix,thebrakingfrictionandwear

behaviorwasthebest.Thisisbecausetheuniformdistributionof

fiberscaneffectivelyimprovetheinechanicalpropertiesandwear

resistanceoftheC/Ccompositematerial.

Conclusion

ThemicrostructureofC/Ccompositematerialhasasignificant

influenceonitsbrakingfrictionandwearbehavior.Theresults

showedthatthefiberorientation,fiberlength,andfiber

distributionareimportantfactorsaffectingtheperformanceofthe

material.Thebestbrakingfrictionandwearbehaviorwasobtained

whenthefiberswereorientedtangentially,thefiberlengthwas

moderate,andthefiberswereuniformlydistributedinthematrix.

Thisstudyprovidesatheoreticalbasisforimprovingthebraking

performanceofC/Ccompositematerials.Furtherresearchonthe

microstructureofC/Ccompositematerialsisneededtooptimize

theirbrakingfrictionandwearbehavior.Forexample,theeffectof

differenttypesofcarbonfibersandmatrixmaterialsonthe

microstructureandpropertiesofC/Ccompositematerialscanbe

investigated.Additionally,theinfluenceofthetemperatureand

humidityonthemicrostructureandpropertiesofC/Ccomposite

materialscanbestudied,sincethesefactorsmayaffectthe

performanceofthematerialsinpracticalapplications.

Furthermore,thewearmechanismofC/Ccompositematerials

underbrakingconditionsneedstobefurtherstudied.TheSEM

observationsofthewornsurfacescanprovideinformationabout

thewearmechanism,whichcanhelpindesigningmoreeffective

brakingsystems.Inaddition,computationalmodelscanbe

developedtosimulatethefrictionandwearbehaviorofC/C

compositematerials,whichcanprovidevaluableinsightsintothe

complexinteractionsbetweenthematerialsandthebrakingsystem.

Insummary,thestudyofthemicrostructureofC/Ccomposite

materialsanditsinfluenceontheirbrakingfrictionandwear

behaviorisofgreatimportanceforimprovingtheperformanceof

thesematerialsinpracticalapplications.Furtherresearchinthis

areacanhelptodevelopnewbrakematerialswithbetter

performanceanddurability.Anotherimportantareaforresearchis

thedevelopmentofnewmanufacturingtechniquesforC/C

compositematerials.ThecurrentmanufacturingmethodsforC/C

composites,suchaschemicalvaporinfiltrationandpyrolysis,have

limitationsintermsofcost,scalability,andreproducibility.

Therefore,thereisaneedtoexplorenewmanufacturingtechniques

thatcanovercometheselimitations.

Oneapproachistouseadditivemanufacturing,suchas3Dprinting,

tofabricateC/Ccompositeparts.Additivemanufacturingcan

enabletheproductionofcomplexgeometriesandreducewasteand

costscomparedtotraditionalmanufacturingmethods.However,

therearechallengesinoptimizingthemicrostructureand

propertiesofC/Ccompositematerialsusingadditive

manufacturing.

Finally,theperformanceofC/Ccompositematerialscouldalsobe

improvedbydevelopingadvancedcoatingsandsurfacetreatments.

Forexample,theapplicationofceramiccoatingscanenhancethe

wearresistanceandreducefrictionbetweenthebrakepadandthe

rotor.Additionally,surfacetreatmentssuchasplasmatreatment,

lasersurfacemodification,andionimplantationcanmodifythe

surfacepropertiesofC/Ccompositematerialstoimprovetheir

frictionandwearbehaviorunderbrakingconditions.

Inconclusion,theresearchonC/Ccompositematerialshasgreat

potentialtoimprovetheperformanceanddurabilityofbraking

systems.Technologicaladvancementsinmicrostructure

optimization,manufacturingtechniques,andsurfacetreatments

canleadtothedevelopmentofnewbrakematerialsthataremore

efficient,longer-lasting,andsafer.Furthermore,researchefforts

canalsobedirectedtowardsexploringtheuseofC/Ccomposites

inotherapplicationswherehigh-performancematerialsare

required.Forinstance,C/Ccompositeshaveshownpromising

resultsinaerospaceanddefenseindustriesastheyexhibithigh

strength,stiffness,andresistancetohightemperatures.Studying

thepropertiesandbehaviorofC/Ccompositesunderextreme

conditionscanleadtothedevelopmentofmorerobustmaterials

fortheseapplications.

Moreover,theuseofC/Ccompositesinenergystorageand

conversiondevices,suchasbatteriesandfuelcells,isalsoa

promisingareaofresearch.Thesematerialscanpotentially

improvethedurability,efficiency,andperformanceofsuch

devices.ExploringthelimitationsandopportunitiesofC/C

compositesinenergystorageandconversioncanpotentially

acceleratethedevelopmentofcleanenergytechnologies.

Finally,theenvironmentalimpactofC/Ccompositematerialscan

alsobeinvestigated.Theproductionofcarbonfibersandthe

manufacturingofC/Ccompositesrequirehighenergyinputs,

whichgeneratesignificantamountsofgreenhousegasemissions.

Researchinganddevelopingsustainablemanufacturingtechniques

andreducingtheenviroiinienlalfootprintofC/Ccompositescan

promotetheirwide-spreaduseinavarietyofindustrial

applications.

Insummary,theresearchanddevelopmentofC/Ccomposite

materialsholdenormouspotentialtoimproveandoptimizevarious

industrialapplications,includingbrakingsystems.Advancements

inmicrostructureoptimization,manufacturingtechniques,surface

treatments,andexploringtheuseofC/Ccompositesinother

applicationscanleadtotheproductionofdurable,efficient,and

sustainablehigh-performancematerials.Oneofthechallengesin

thedevelopmentofC/Ccompositesistheoptimizationoftheir

microstructure.Themicrostructureplaysacriticalrolein

determiningthemechanicalandthermalpropertiesofthese

materials.Researchersareexploringadvancedcharacterization

techniquestostudythemicrostructureofC/Ccompositesat

differentlengthscales,rangingfromthecarbonfibersurfacetothe

overallcompositestructure.Thisapproachcanleadtoa

fundamentalunderstandingofthestructure-propertyrelationships

ofC/Ccompositesandaidintheiroptimization.

AnotherstrategytoimprovetheperformanceofC/Ccompositesis

todevelopadvancedmanufacturingtechniques.Researchersare

exploringvariousmethodstofabricateC/Ccomposites,including

chemicalvaporinfiltration,liquidmetalinfiltration,andpyrolysis.

Bydevelopingadvancedmanufacturingtechniques,researchers

canproduceC/Ccompositeswithimprovedstructuralintegrity,

thermalstability,andsuperiormechanicalproperties.

SurfacetreatmentscanalsoimprovetheperformanceofC/C

composites.Surfacetrealnienls,suchascoalingsand

functionalization,canmodifythesurfacechemistryand

morphologyofC