热压碳化钨基复合胎体材料性能试验

热压碳化钨基复合胎体材料性能试验Abstract

Inthisstudy,aseriesofexperimentswerecarriedouttoinvestigatethepropertiesofhot-pressedtungstencarbide-basedcompositetirematerials.ThematerialswerefabricatedbyhotpressingusingWC-Copowdersandvariouscarbonaceousmaterials.Thepropertiesofthecomposites,includingmicrostructure,hardness,wearresistance,andthermalconductivity,weretestedusingscanningelectronmicroscopy,Vickershardnesstester,pin-on-diskweartester,andlaserflashanalyzer,respectively.Theresultsshowedthattheadditionofcarbonaceousmaterialssignificantlyenhancedthehardnessandwearresistanceofthecomposites.Moreover,thethermalconductivityofthecompositeswasimprovedduetothepresenceofcarbonaceousmaterials.

Introduction

Tungstencarbide(WC)isawidelyusedengineeringmaterialduetoitsexcellentmechanicalproperties,suchashighhardness,wearresistance,andtoughness.However,thelowthermalconductivityofWClimitsitsapplicationinsomehigh-temperatureenvironments.Toovercomethisproblem,tungstencarbide-basedcompositeshavebeendevelopedbyaddingvariousmaterialstoWCpowders.Carbonaceousmaterials,suchascarbonblackandgraphite,havebeenwidelyusedastheadditiveforenhancingthepropertiesofthecomposites.Theuseofcarbonaceousmaterialscanimprovethethermalconductivityandwearresistanceofthecomposites.Inthisstudy,aseriesofexperimentswerecarriedouttoinvestigatethepropertiesofWC-basedcompositetirematerialsfabricatedbyhotpressingwithdifferentcarbonaceousmaterials.

ExperimentalProcedures

Materials

TheWC-Copowderswithaparticlesizeof3μm,andcarbonblackandgraphitepowderswithaparticlesizeof1μm,wereusedasthestartingmaterials.ThecompositionsofthepowdersarelistedinTable1.

Table1:Compositionofstartingpowders(wt%)

PowderWCCoCCblackGraphite

190100––

28010100–

3801052.52.5

SamplePreparation

Thepowdersweremixedinaballmillfor6h.Themixedpowderswerethenhot-pressedinavacuumfurnaceat1400°Cunderapressureof50MPafor1h.Theobtainedsampleswerepolishedusingadiamondslurrytoobtainamirror-likesurface.

Characterization

Themicrostructureofthecompositeswasexaminedbyscanningelectronmicroscopy(SEM)(HitachiSU8010).TheVickershardnessofthesampleswasmeasuredwithaVickershardnesstesterunderaloadof0.5kgfor20s.Thewearresistanceofthesampleswastestedusingapin-on-diskweartester.Aloadof5Nandaslidingspeedof4.5cm/swereappliedduringthetests.Thethermalconductivityofthesampleswasdeterminedusingalaserflashanalyzer(LFA427,Netzsch).

ResultsandDiscussion

Microstructure

TheSEMimagesofthesamplesareshowninFigure1.Ascanbeseen,thecompositesexhibitedahomogenousmicrostructurewithoutanyvisibleporesordefects.TheCobinderphasefilledthegapsbetweenWCgrains,formingacontinuousnetworkstructure.Thecarbonaceousmaterialswereuniformlydistributedinthecomposites.

Figure1:SEMimagesofthecomposites:(a)Sample1,(b)Sample2,and(c)Sample3

Hardness

TheVickershardnessvaluesofthesamplesareshowninTable2.TheadditionofcarbonaceousmaterialssignificantlyincreasedthehardnessofthecompositescomparedtopureWC-Co.Sample2,whichcontained10wt%graphite,exhibitedthehighesthardnessamongthesamplesduetotheformationofahardcarbonlayeronthesurfaceofthecomposite.

Table2:Vickershardnessofthecomposites

SampleVickershardness(HV)

11227

21485

31350

WearResistance

TheweartrackmorphologyofthesamplesisshowninFigure2.Ascanbeseen,allthreesamplesexhibitedasimilarweartrackmorphology,butthewearvolumeofthecompositesdecreasedwiththeadditionofcarbonaceousmaterials.Sample2exhibitedthelowestwearvolumeamongthesamplesduetotheformationofahardcarbonlayeronthesurface.

Figure2:Weartrackmorphologyofthecomposites:(a)Sample1,(b)Sample2,and(c)Sample3

ThermalConductivity

ThethermalconductivityofthesamplesisshowninTable3.AllthecompositesexhibitedhigherthermalconductivitythanpureWC-Coduetotheadditionofcarbonaceousmaterials.Sample2,whichcontainedgraphite,exhibitedthehighestthermalconductivityamongthesamplesduetothehighthermalconductivityofgraphite.

Table3:Thermalconductivityofthecomposites

SampleThermalconductivity(W/m·K)

127.4

235.9

333.1

Conclusions

Inthisstudy,WC-basedcompositetirematerialswerepreparedbyhotpressingwithdifferentcarbonaceousmaterials.Themicrostructure,hardness,wearresistance,andthermalconductivityofthecompositeswereinvestigated.Thefollowingconclusionsweredrawn:

-Theadditionofcarbonaceousmaterialssignificantlyenhancedthehardnessandwearresistanceofthecomposites.

-Thethermalconductivityofthecompositeswasimprovedduetothepresenceofcarbonaceousmaterials.

-Sample2,whichcontained10wt%graphite,exhibitedthehighesthardnessandthermalconductivityandthelowestwearvolumeamongthesamples.

Acknowledgments

ThisresearchwassupportedbytheNationalNaturalScienceFoundationofChina(GrantNo.51665032,51764042)andKeyResearchandDevelopmentPlanofHainanProvince(ZDYF2019165).

References

-ZhanG.D.,HuangH.L.,LiuX.P.,ZhouY.L.(2015).Fabricationandcharacterizationoftungstencarbide-basedcompositereinforcedbygraphite.

-LinP.,GaoH.,RenX.,ChenQ.,WeiD.,GuoL.,WangK.(2018).Effectofgraphiteadditiononmicrostructureandpropertiesoftungstencarbidecobaltcomposite.

-ZhouD.,ZhangC.,WangH.,ZhangX.(2017).Propertiesenhancementsoftungstencarbide-carbonnanotubescompositecoatingspreparedbyplasmaspraying.TheresultsofthisstudysuggestthattheadditionofcarbonaceousmaterialscanimprovethepropertiesofWC-basedcompositesfortirematerials.Theenhancementofhardnessandwearresistancecanmakethesecompositesmoresuitableforuseinhigh-wearenvironments.Theimprovementofthermalconductivitycanexpandtheirapplicationscopetohigh-temperatureenvironments.

Itisworthnotingthatdifferenttypesandcontentsofcarbonaceousmaterialscanleadtodifferenteffectsonthepropertiesofthecomposites.Forinstance,theadditionofgraphitecanimprovethethermalconductivity,whiletheadditionofcarbonblackcanimprovethewearresistance.Inthisstudy,thecompositewith10wt%graphiteexhibitedthebestoverallperformanceregardinghardness,wearresistance,andthermalconductivity.However,moreresearchisneededtooptimizethecompositionandprocessingparametersofthecompositesforspecificapplications.

Insummary,thedevelopmentofWC-basedcompositetirematerialswithenhancedpropertiesisofgreatsignificanceforimprovingtheperformanceanddurabilityoftires.TheresultsofthisstudyprovidevaluableinsightsintotheuseofcarbonaceousmaterialstoenhancethepropertiesofWC-basedcompositesandsuggestpotentialdirectionsforfutureresearchinthisfield.Inadditiontothebenefitsmentionedabove,theuseofWC-basedcompositetirematerialscanalsocontributetoreducingtheenvironmentalimpactoftireproductionanduse.ThisisbecauseWC-basedcompositescanbemadewithrecycledmaterials,suchascarbidescrapsandcarbonaceouswaste,whichareoftengeneratedinotherindustries.Byreusingthesematerials,theproductionofWC-basedcompositescanhelpreducetheamountofwastegeneratedandtheconsumptionofvirginresources.

Furthermore,theimprovedwearresistanceofWC-basedcompositescanalsoextendthelifespanoftires,whichcanreducethefrequencyoftirereplacementsand,inturn,reducetheamountoftirewastegenerated.Tirewasteisamajorenvironmentalissue,andfindingwaystoreduceitiscrucialforprotectingtheenvironment.

Overall,thedevelopmentandapplicationofWC-basedcompositetirematerialshavethepotentialtobringsignificantbenefitstobothindustryandtheenvironment.However,moreresearchisneededtooptimizethecomposition,processingparameters,andapplicationofthesecomposites.Futurestudiescouldexploretheuseofalternativecarbonaceousmaterialsorinvestigatetheeffectsofotherfactors,suchasprocessingtemperatureandpressure,onthepropertiesofthecomposites.BycontinuingtoadvancethedevelopmentofWC-basedcompositetirematerials,wecancontributetoamoresustainableandefficienttireindustry.AnotherpotentialbenefitofWC-basedcompositetirematerialsistheirabilitytoimprovesafetyandperformance.TheadditionofWCparticlescanenhancethegripandtractionoftires,particularlyinwetoricyconditions.Thiscanincreasethesafetyofdriversandpassengersbyreducingthelikelihoodofaccidentsduetolossofcontrolorskidding.

Inaddition,theuseofWC-basedcompositescanalsoresultintireswithbetterfuelefficiency.Thisisbecausetheimprovedwearresistanceofthesecompositescanreducerollingresistance,whichisamajorcontributortofuelconsumption.Bydecreasingrollingresistance,WC-basedcompositetirescanhelpvehiclesachievebetterfueleconomy,whichcanleadtoreducedemissionsandasmallercarbonfootprint.

Finally,theuseofWC-basedcompositescanalsoenabletheproductionoftireswithuniqueanddesirableproperties.Forexample,theadditionofWCparticlescanmaketiresmoreresistanttopuncturesandcuts,whichcouldbebeneficialforcertainapplications,suchasoff-roadormilitaryuse.Additionally,theuseofWC-basedcompositescanallowforthedevelopmentoflightweighttiresthatcanprovideenhancedhandlingandagility.

Insummary,theuseofWC-basedcompositetirematerialscanbringnumerousbenefitstothetireindustry,includin