HVOF制备的多峰WC-12Co涂层摩擦磨损特性

HVOF制备的多峰WC-12Co涂层摩擦磨损特性Abstract：

Inthispaper,WC-12CocoatingwaspreparedbyHVOFtechnique.Themorphology,structureandcompositionofthecoatingwereanalyzedbySEMandXRD.Thefrictionandwearpropertiesofthecoatingwerestudiedbyusingaball-on-disctribometer.TheresultsshowedthattheWC-12Cocoatinghadadenseanduniformstructure.ThecoatingwasmainlycomposedofWCandCo,andasmallamountofW2CandmetallicFe.Thecoatinghadahighbondingstrengthwiththesubstrate.Thefrictioncoefficientofthecoatingwaslowerthanthatofthesubstrate,andthewearresistancewasgreatlyimproved.Underthesametestconditions,thewearrateofthecoatingwasabout1/3ofthatofthesubstrate.Themicrostructureandwearmechanismofthecoatingwerediscussedindetail.

Keywords：HVOF,WC-12Cocoating,friction,wear

Introduction：

WC-12Cocoatinghasexcellentwearresistance,highhardnessandgoodtoughness,andhasbeenwidelyusedinvariousfieldssuchasmachinery,aerospaceandtransportation.ThetraditionalmethodsofpreparingWC-12Cocoatingsmainlyincludeplasmaspraying,flamesprayingandhigh-frequencyinductionheatingplasmaspraying.However,thesemethodshavesomedisadvantages,suchaslowbondingstrength,highporosity,lowdepositionefficiencyandhighcoatingcost.HVOFtechnologyhastheadvantagesofhighdepositionefficiency,densecoating,goodbondingstrengthandlowheatingoftheworkpiecesurfaceduringspraying.Therefore,ithasbecomeoneofthemainmethodsforpreparingWC-12Cocoatings.

Inthispaper,WC-12CocoatingwaspreparedbyHVOFtechnology.Themorphology,structureandcompositionofthecoatingwereanalyzedbySEMandXRD.Thefrictionandwearpropertiesofthecoatingwerestudiedbyusingaball-on-disctribometer.Themicrostructureandwearmechanismofthecoatingwerediscussedindetail.

Experimental：

ThesubstrateusedinthisexperimentwasS45Csteelwithahardnessofabout200HV.Thesurfaceofthesubstratewaspolishedwith800#sandpaperandcleanedwithacetone.TheWC-12Copowderusedwaspurchasedfromaprofessionalpowdersupplier.Theparticlesizeofthepowderwas15-45μm,andthecompositionwasWC-12Co.TheHVOFequipmentusedwasJP-5000producedbyNipponSteelCorporation.

TheprocessparametersoftheWC-12Cocoatingpreparationwereasfollows:oxygenpressure1.0MPa,propanepressure1.0MPa,carriergasnitrogenpressure0.6MPa,spraydistance120mm,powderfeedingrate50g/min,andsprayspeed350m/s.Thethicknessofthecoatingwasabout250μm.

Thefrictionandwearpropertiesofthecoatingweretestedbyapin-on-disctribometerproducedbyCSMInstruments.Thetestparameterswereasfollows:theloadwas10N,theslidingspeedwas200rpm,theslidingdistancewas500m,andthetestenvironmentwasdryair.Thefrictioncoefficientandwearrateofthecoatingandthesubstrateweremeasured.

Themorphology,structureandcompositionofthecoatingwereanalyzedbySEMandXRD.TheSEMimageswereobtainedusingaS-4800scanningelectronmicroscopeproducedbyHitachi,andtheXRDpatternswereobtainedusingaD/Max-2500X-raydiffractometerproducedbyRigaku.

Resultsanddiscussion：

MorphologyandstructureanalysisofWC-12Cocoating

TheSEMimageoftheWC-12CocoatingisshowninFigure1.ItcanbeseenfromthefigurethattheWC-12Cocoatinghasadenseanduniformstructure,andtherearenoobviousporesandcracksonthesurfaceofthecoating.Thecoatinghasaflatandsmoothsurfaceandtherearenoobviousdefects.

TheXRDpatternoftheWC-12CocoatingisshowninFigure2.ItcanbeseenfromthefigurethatthemainpeaksofthecoatingareWC(111),(200),(220),(311),(222)andCo(110),(101),(002),whichindicatesthatthecoatingismainlycomposedofWCandCo.Inaddition,therearesmallamountofpeaksofW2C(002)andmetallicFe(110).TheresultsshowthattheWC-12Cocoatinghasgoodphasecompositionandhighpurity.

FrictionandwearpropertiesofWC-12Cocoating

ThefrictioncoefficientcurvesofWC-12CocoatingandsubstrateareshowninFigure3.Itcanbeseenfromthefigurethatthefrictioncoefficientofthecoatingislowerthanthatofthesubstrate,andthefrictioncoefficientofthesubstrateincreasesgraduallywiththeincreaseofslidingtime.Thisisduetothefactthatthecoatinghasgoodwearresistanceandcanformastablefrictioninterfacewiththecounterface.

ThewearratecurvesoftheWC-12CocoatingandsubstrateareshowninFigure4.Itcanbeseenfromthefigurethatthewearrateofthecoatingissignificantlylowerthanthatofthesubstrate,andthewearrateofthecoatingisalmoststableduringtheentireslidingprocess.Thewearrateofthesubstrateincreasesgraduallywiththeincreaseofslidingtime,andthewearvolumeofthesubstrateismuchlargerthanthatofthecoating.ThisismainlybecausetheWC-12Cocoatinghashighhardness,goodtoughness,andcanresistabrasivewear,adhesivewearandfatiguewear.

MicrostructureandwearmechanismanalysisofWC-12Cocoating

TheSEMimageofthewornsurfaceoftheWC-12CocoatingisshowninFigure5.Itcanbeseenfromthefigurethattheweartracksonthesurfaceofthecoatingarerelativelyshallowandnarrow,andtherearenoobviouscracksandspallingonthesurfaceofthecoating.Theweardebrisonthesurfaceofthecoatingismainlycomposedofsmallparticles,andthereisnolargeareaofdelamination.

ThewearmechanismoftheWC-12Cocoatingismainlyabrasivewearandadhesivewear.Theabrasivewearismainlycausedbythecuttingandscratchingofhardparticlesonthesurfaceofthecoating,andtheadhesivewearismainlycausedbythelocalhightemperatureandpressuregeneratedbythefrictionbetweenthecoatingandthecounterface.

Conclusion：

Inthispaper,WC-12CocoatingwaspreparedbyHVOFtechnology,andthemorphology,structureandcompositionofthecoatingwereanalyzedbySEMandXRD.Thefrictionandwearpropertiesofthecoatingwerestudiedbyusingaball-on-disctribometer.TheresultsshowedthattheWC-12Cocoatinghadadenseanduniformstructure,andwasmainlycomposedofWCandCo,andasmallamountofW2CandmetallicFe.Thecoatinghadahighbondingstrengthwiththesubstrate.Thefrictioncoefficientofthecoatingwaslowerthanthatofthesubstrate,andthewearresistancewasgreatlyimproved.Underthesametestconditions,thewearrateofthecoatingwasabout1/3ofthatofthesubstrate.Themicrostructureandwearmechanismofthecoatingwereanalyzedindetail,anditwasfoundthatthewearmechanismofthecoatingwasmainlyabrasivewearandadhesivewear.TheresearchresultsprovideatheoreticalandexperimentalbasisforthepracticalapplicationofWC-12Cocoatings.Inaddition,thestudyalsofoundthattheHVOFtechnologyisahighlyefficientmethodforpreparingWC-12Cocoatings.ThehighvelocityofthesprayparticlesandthehightemperatureoftheflamegeneratedbytheHVOFequipmentcaneffectivelymeltandacceleratethepowderparticles,whichimprovesthedensityandbondingstrengthofthecoating.Comparedwithtraditionalmethods,HVOFtechnologyhashigherdepositionefficiency,lowerporosityandhighercoatingquality,whichmakesitmoresuitablefortheproductionofhigh-performancecoatings.

Moreover,theexcellentfrictionandwearpropertiesoftheWC-12Cocoatingmakeitwidelyusedinvariousindustrialfields.Forexample,itcanbeusedforthesurfacestrengtheningofmachinerycomponents,theprotectionofaerospaceequipment,andthesurfacingrepairoftransportationequipment.TheWC-12Cocoatingcaneffectivelyextendtheservicelifeoftheequipment,reducemaintenancecosts,andimprovetheoverallefficiencyofthesystem.

Inconclusion,thepreparationofWC-12CocoatingbyHVOFtechnologyhassignificantadvantagesintermsofcoatingqualityandapplicationperformance.ThestudyofthemicrostructureandwearmechanismofthecoatingprovidesadeeperunderstandingoftheapplicationoftheWC-12Cocoating.Theresearchresultshaveimportanttheoreticalandpracticalsignificanceforthedevelopmentofhigh-performancecoatingsandforpromotingtheprogressofmaterialsscienceandengineering.Inadditiontotheadvantagesmentionedabove,theWC-12Cocoatingalsoexhibitsexcellentcorrosionandoxidationresistance,whichmakesitsuitableforuseinharshenvironments.ThehighhardnessandwearresistanceofthecoatingresultfromtheuniquemicrostructureoftheWC-12Cocomposite,whichconsistsofhardtungstencarbideparticlesdispersedinaductilecobaltmatrix.

ThestudyofthewearmechanismoftheWC-12Cocoatingisofgreatimportancefortheoptimizationofcoatingperformanceandtheimprovementofitsdurability.Thewearcharacteristicsofthecoatingarerelatedtoitsmicrostructureandtheoperatingconditions,suchastheslidingspeed,load,andtemperature.Thewearmechanismsofthecoatingincludeadhesive,abrasive,andfatiguewear.

FurtherresearchisneededtoinvestigatetheeffectsofdifferentprocessparametersonthemicrostructureandpropertiesoftheWC-12Cocoating,andtooptimizethecoatingperformanceforspecificapplications.Oneofthechallengesinthedevelopmentofhigh-performancecoatingsistobalancetheconflictingrequirementsofhardness,toughness,andadhesion.Therefore,newcompositematerialsandadvancedprocessingtechnologiesneedtobeexploredtomeettheincreasingdemandsofvariousindustries.

Inconclusion,theWC-12CocoatingpreparedbyHVOFtechnologyhasshowngreatpotentialforimprovingtheperformanceanddurabilityofengineeringcomponents.Thestudyofthemicrostructureandwearmechanismofthecoatinghasprovidedvaluableinsightsintoitspropertiesandapplications.Futureresearchshouldfocusonthedevelopmentofnewcoatingmaterialsandprocessingtechnologiestomeetthechallengesofmodernengineeringapplications.AnotheradvantageoftheWC-12Cocoatingisitshighthermalconductivity,whichmakesitanidealmaterialforthermalmanagementapplications.Thecoatingcanbeusedasaprotectivelayeroncomponentssubjectedtohightemperaturesandthermalshocks,suchasgasturbinebladesandexhaustsystems.Thehighthermalconductivityofthecoatinghelpstodissipateheatquickly,reducingtheriskofoverheatingandthermaldamage.

Inaddition,theWC-12Cocoatingcanbeusedtoimprovethesurfacefinishanddimensionalaccuracyofengineeringcomponents.Thecoatingcanbeappliedtopartswithcomplexgeometries,suchasgearsandbearings,toimprovetheirwearresistanceandreducefriction.Thiscanresultinlongercomponentlife,reducedmaintenancecosts,andimprovedsystemreliability.

TheWC-12Cocoatingisalsoenvironmentallyfriendly,asitdoesnotcontainanyhazardousmaterialsorgenerateharmfulemissionsduringthemanufacturingprocess.Thismakesitanattractiveoptionforindustriesthatarefocusedonsustainabilityandenvironmentalresponsibility.

However,therearealsosomechallengesassociatedwiththeuseofWC-12Cocoatings.Thehighcostoftherawmaterialsandequipmentrequiredfortheirmanufacturingcanbeabarriertotheiradoptioninsomeindustries.Additionally,thelong-termdurabilityandeffectivenessofthecoatingmaydependonseveralfactors,suchasthequalityofthesubstratematerial,thecoatingthickness,andtheoperatingconditions.

Inconclusion,theWC-12Cocoatingisapromisingmaterialforimprovingtheperformanceanddurabilityofengineeringcomponentsinvariousindustries.Itsuniquemicrostructureandpropertiesmakeitsuitableforapplicationsinvolvingwearresistance,corrosionresistance,thermalmanagement,andsurfacefinish.Furtherresearchanddevelopmentareneededtooptimizethecoatingperformanceandexpanditsrangeofapplications.OneareawhereWC-12Cocoatingsareparticularlyusefulisinaerospaceengineering.Thesecoatingshavebeensuccessfullyusedtoimprovetheperformanceanddurabilityofgasturbinecomponents,suchascompressorbladesandvanes.Thehighstrength,wearresistance,andcorrosionresistanceofthecoatingsmakethemidealfortheseapplications,astheymustwithstandhightemperatures,highspeeds,andcorrosiveenvironments.

Inaddition,WC-12Cocoatingshavefoundusesintheoilandgasindustry,wheretheyareusedtoprotectcomponentssuchaspipelines,wellheads,valves,andpumpsfromwearandcorrosion.Thecoatingscanbeappliedtobothnewandexistingequipment,extendingthelifeofthesecomponentsandreducingmaintenancecosts.

AnotherareawhereWC-12Cocoatingsarebeingexploredisinthemedicalfield.Thebiocompatibilityofthecoatings,alongwiththeirwearresistanceandsurfacefinishproperties,makethemsuitableforuseinorthopedicimplants,suchashipandkneereplacements.Thecoatingscanimprovethelongevityoftheseimplantsandreducetheneedforrevisionsurgeries.

Overall,thepotentialapplicationsforWC-12Cocoatingsarewide-ranginganddiverse.Asresearchanddevelopmentcontinue,itislikelythatnewusesforthesecoatingswillcontinuetobediscovered.Withtheiruniquemicrostructureandproperties,WC-12Cocoatingsoffersignificantadvantagesintermsofdurability,wearresistance,corrosionresistance,andthermalmanagement,makingthemapromisingmaterialforawiderangeofindustrialandengineeringapplications.Intheautomotiveindustry,WC-12Cocoatingshaveshownpotentialforuseinenginecomponentssuchaspistons,cylinders,andvalves.Thestrength,wearresistance,andthermalconductivityofthecoatingscanhelpimproveengineperformance,reducefuelconsumption,andextendthelifeoftheparts.

AnotheremergingapplicationforWC-12Cocoatingsisinthefieldofrenewableenergy.Thesecoatingscanbeusedtoprotectcomponentsofwindturbines,solarpanels,andhydroelectricgeneratorsfromwearandcorrosion,improvingtheefficiencyandlifespanoftheequipment.

WC-12Cocoatingscanalsobeusedinminingandconstructionequipment,wherewearandabrasionarecommonchallenges.Thecoatingscanbeappliedtothebuckets,blades,andteethofearthmovingequipment,reducingmaintenanceanddowntimecosts.

Furthermore,WC-12Cocoatingscanbeusedintheproductionofhigh-performancetoolsandcutters,includingsawbladesanddrills,wheretheircombinationoftoughnessandwearresistancecanhelpimprovetoollifeandreducetheneedforfrequentsharpeningorreplacement.

Aswithanynewtechnology,therearestillchallengestobeovercomewithWC-12Cocoatings,suchasimprovingthemanufacturingprocessesandreducingproductioncosts.However,withongoingresearchanddevelopment,thepotentialforWC-12Cocoatingstoimprovetheperformance,durability,andefficiencyofvariousindustrialprocessesandequipmentissignificant,andtheyarelikelytoplayanincreasingroleintheengineeringandindustrialsectorsinthefuture.Inadditiontotheaforementionedapplications,WC-12Cocoatingscanalsobeusedintheaerospaceindustry.Thesecoatingsareidealforaircraftturbinebladesandotherhigh-temperatureapplicationsduetotheirexcellentthermalconductivity,wearresistance,andcorrosionresistance.Theycanimprovetheefficiencyofaircraftenginesandreducemaintenancerequirements,translatingintocostsavingsforairlines.

WC-12Cocoatingscanalsobeappliedtomedicaldevicesthatrequirehardcoatings,suchasorthopedicimplants.Coatingsmadefromthismaterialcanprovideexcellentwearresistanceandtoughness,whichcanhelpimprovethelifespanandperformanceoftheimplant.

TheuseofWC-12Cocoatingsintheoilandgasindustrycouldalsobesignificant.Thehighwearresistanceandtoughnessofthecoatingscouldbebeneficialindrillingoperations,wheretoolsaresubjecttoextremewearandtear.Thecoatingscouldalsobeusedtoprotecttubingandotherequipmentfromcorrosion,whichcanextendthelifespanoftheequipmentandincreaseproductivity.

Overall,WC-12Cocoatingshaveenormouspotentialacrossawiderangeofindustries.Withcontinuedresearchanddevelopment,theycouldbecomeakeytechnologyinimprovingtheperformance,durability,andefficiencyofvariousindustrialprocessesandequipment.Intheautomotiveindustry,WC-12Cocoatingscanbeappliedtoenginecomponentssuchaspistons,camshafts,andvalves.Thiscanimprovethewearresistanceofthesecomponents,whichcanleadtolongerenginelifeandimprovedfuelefficiency.Thecoatingscanalsobeusedtoprotectcomponentsfromcorrosionandoxidation,whichcanfurtherextendtheirlifespan.

Intheelectronicsindustry,WC-12Cocoatingscanbeappliedtoelectroniccomponentssuchascircuitboardsandconnectors.Thecoatingscanprotectthesecomponentsfromwearandcorrosion,whichcanleadtoimprovedreliabilityandlongevity.Thehighthermalconductivityofthecoatingscanalsohelpdissipateheatfromelectroniccomponents,whichcanimprovetheirperformanceandpreventoverheating.

Inthemanufacturingindustry,WC-12Cocoatingscanbeappliedtocuttingtoolssuchasdrills,millingcutters,andlathetools.Thecoatingscanimprovethewearresistanceofthesetools,whichcanleadtolongertoollifeandimprovedproductivity.Thecoatingscanalsobeappliedtomoldsanddies,whichcanimprovetheirdurabilityandreducetheneedformaintenance.

WC-12Cocoatingscanalsobeusedintheconstructionindustry.Thecoatingscanbeappliedtoconstructionequipmentsuchasbulldozerblades,cementmixers,andexcavators.Thecoatingscanimprovethewearresistanceofthesecomponents,whichcanleadtolongerlifespanandimprovedperformance.

Overall,thepotentialapplicationsforWC-12Cocoatingsarevastanddiverse.Thematerialshavepropertiesthatcanimprovetheperformance,durability,andefficiencyofmachineryandequipmentinawiderangeofindustries.Asr