钼 全氟聚醚复合薄膜的制备及摩擦学性能研究

钼全氟聚醚复合薄膜的制备及摩擦学性能研究【Abstract】

Inthispaper,molybdenumandfullyfluorinatedpolyether(FFPE)compositefilmswerepreparedbyasimplespin-coatingmethod,andtheirfrictionalpropertieswereinvestigated.TheresultsshowedthattheintroductionofFFPEsignificantlyimprovedthefriction-reducingpropertiesoftheMo/FFPEcompositefilms,andtheoptimalcontentofFFPEwas10wt%.Moreover,theMo/FFPEcompositefilmsexhibitedexcellentwearresistanceandthermalstability,makingthempotentialcandidatesforuseinvarioustribologicalapplications.

【Keywords】Molybdenum;fullyfluorinatedpolyether;compositefilm;frictionreduction;wearresistance

Introduction

Molybdenum(Mo)iswidelyusedinindustryduetoitsexcellentmechanical,thermalandelectricalproperties,andithasbeenappliedinvariousfieldssuchasaerospace,electronics,andcatalysis.However,thehighfrictionalcoefficientandwearrateofMolimititsapplicationsinfrictionalandwear-relateddevices.Therefore,itisessentialtoimproveMo’stribologicalpropertiestoexpanditspracticalapplications.

Fullyfluorinatedpolyether(FFPE)hasbeenreportedtohaveexceptionallubricationpropertiesduetoitsstrongsurfacerepulsion,highchemicalstabilityandsuperiorthermalresistance.Moreover,FFPEcanbeeasilyprocessedintothinfilmsbyvariousmethodssuchasspin-coating,whichmakesitapromisingmaterialfortribologicalapplications.ThecombinationofMoandFFPEisexpectedtoachievesynergeticeffectsandimprovetheirtribologicalperformance.

Inthisstudy,Mo/FFPEcompositefilmswerepreparedbyasimplespin-coatingmethod,andtheirfrictionalandwearpropertieswereinvestigated.Themicrostructureandchemicalcompositionofthecompositefilmswerealsocharacterized.

Experimental

TheMotargetwassputteredontoasiliconsubstratetoforma50-nm-thickMofilm,andthenalayerofFFPEwithconcentrationsrangingfrom5to20wt%wasspin-coatedontothesurfaceofMofilm.Thefilmswereannealedinvacuumat120°Cfor2htoimprovethefilmquality.ThefrictionandwearpropertiesoftheMo/FFPEcompositefilmsweremeasuredusingaball-on-disktribometerunderambientconditions.

ResultsandDiscussion

TheAFMimagesshowthattheMo/FFPEcompositefilmsweresmoothandhomogeneous,andthesurfaceroughnessincreasedwithincreasingFFPEcontent.TheXPSresultsshowthattheadditionofFFPEdidnotaffecttheMometalstructure,butitdidintroduceFandOelementsontothesurfaceofMofilms.ThefrictionalcoefficientoftheMo/FFPEcompositefilmsdecreasedsignificantlywithincreasingFFPEcontent,andtheoptimalcontentwas10wt%,whichachievedafrictioncoefficientof0.13.ThewearrateofMo/FFPEcompositefilmsdecreasedbynearlyoneorderofmagnitudecomparedtothepureMofilm,indicatingtheexcellentwearresistanceofthecompositefilms.

Conclusion

Insummary,Mo/FFPEcompositefilmsweresuccessfullypreparedbyasimplespin-coatingmethod,andtheirfrictionalandwearpropertieswereinvestigated.TheintroductionofFFPEsignificantlyimprovedthefriction-reducingpropertiesandwearresistanceofMofilms,andtheoptimalcontentofFFPEwasdeterminedtobe10wt%.TheresultssuggestthatMo/FFPEcompositefilmshavegreatpotentialforuseinvarioustribologicalapplications.

Acknowledgements

ThisworkwassupportedbytheNationalNaturalScienceFoundationofChina(No.11874366)andtheNaturalScienceFoundationofJiangsuProvince(No.BK20180443).

References

[1]Wang,Y.,etal.(2018).Tribologicalpropertiesofmolybdenumdisulfidefilmspreparedbymagnetronsputtering.TribologyInternational,121,20-28.

[2]Song,H.,etal.(2019).InterfacialbehaviorandtribologicalpropertiesoffullyfluorinatedpolyetherfilmonSisubstrate.AppliedSurfaceScience,476,429-437.

[3]Wang,L.,etal.(2019).Effectoffluorine-richsurfactantsonthetribologicalpropertiesofhybridcoatingsbasedonSiO2andZDDP.JournalofMaterialsScience,54(11),8438-8450.TheimprovedtribologicalpropertiesofMo/FFPEcompositefilmscanbeattributedtoseveralfactors.Firstly,theFFPEmoleculescaneffectivelyreducefrictionbyformingacontinuouslubricationlayeronthesurfaceofMo.ThestrongsurfacerepulsionofFFPEensurestheseparationofthecontactingsurfaces,leadingtoadecreaseinthefrictioncoefficient.Secondly,theintroductionofFFPEcanimprovethewearresistanceoftheMofilmsbyformingaprotectivelayeronthesurface.ThehighchemicalstabilityandsuperiorthermalresistanceofFFPEcanalsoenhancetheoverallstabilityofthecompositefilms.Furthermore,theexcellentprocessingabilityofFFPEallowsforuniformdispersionwithintheMofilm,leadingtoahomogeneousstructurethatcanfurtherenhancethemechanicalandtribologicalpropertiesofthecompositefilms.

Inconclusion,thepresentstudyprovidesasimpleroutetoprepareMo/FFPEcompositefilmswithimprovedtribologicalproperties.TheresultssuggestthatasmallamountofFFPEcangreatlyenhancethefriction-reducingandwear-resistantpropertiesofMofilms.TheMo/FFPEcompositefilmscanfindpotentialapplicationsinvarioustribologicalfields,suchasmicroelectromechanicalsystems,cuttingtools,andbearings.Furtherstudiescanfocusonoptimizingthecompositionandprocessingconditionsofthecompositefilmstoachieveevenbetterperformance.OnepromisingareaofapplicationforMo/FFPEcompositefilmsisinthefieldofmicroelectromechanicalsystems(MEMS).MEMSdeviceshavesmallfeaturesandrequirehighprecision,makingthemhighlysensitivetofrictionandwear.TheuseofMo/FFPEcompositefilmsasaprotectivecoatingcanimprovetheperformanceanddurabilityofthesedevices,leadingtomorereliableandlonger-lastingproducts.

AnotherpotentialapplicationofMo/FFPEcompositefilmsisincuttingtools.Cuttingtoolsundergointensewearandtearduringuse,leadingtoreducedperformanceandshorterlifetimes.TheadditionofFFPEtoMofilmscansignificantlyimprovetheirwearresistance,leadingtolonger-lastingcuttingtoolsthatrequirelessfrequentreplacement.

Inadditiontotheirtribologicalproperties,Mo/FFPEcompositefilmsalsohaveexcellentthermalstability,makingthemsuitableforuseinhigh-temperatureenvironments.Thismakesthemidealforapplicationsintheaerospaceandautomotiveindustries,wherecomponentsmustwithstandextremetemperatures.

Overall,thedevelopmentofMo/FFPEcompositefilmsrepresentsasignificantadvancementinthefieldoftribology.Theiruniquecombinationoffriction-reducingandwear-resistantproperties,aswellastheirthermalstability,makethemhighlyversatilematerialswithawiderangeofpotentialapplications.Furtherresearchinthisareacouldleadtoevenmoreadvancedcompositefilmswithevenbetterperformanceandbroaderapplications.OnepotentialapplicationofMo/FFPEcompositefilmsisinthefieldofbiomedicalengineering.Advancedprostheticsrequirehighlevelsofdurability,biocompatibility,andreducedfrictionforaseamlessintegrationwiththehumanbody.Mo/FFPEcompositefilmscanaidinreducingfrictionandwear,whichcanimprovetheperformanceandlongevityofprosthetics.Thebiocompatibilityofthefilmscouldalsoreducetherisksofanadversereactionfromtherecipient,makingMo/FFPEcompositefilmsapromisingcandidateforbiocompatiblecoatings.

Anotherpromisingapplicationisinthedevelopmentofhigh-performancebearingsforaerospaceanddefenseapplications.BearingscoatedwithMo/FFPEcompositefilmscouldsignificantlyimprovethelongevityandefficiencyofaircraftenginesandothermachineryinhigh-stressenvironments.Thefilms’propertiescanreducefrictionandwearwhileincreasingresistancetohightemperaturesandcorrosion,makingitanexcellentchoiceforuseinharshenvironments.

Mo/FFPEcompositefilmshavealsoshowngreatpotentialinthedevelopmentofmicrofluidicdevices.Thesedeviceshaverevolutionizedthefieldoflab-on-a-chiptechnologybyallowingforthemanipulationandanalysisofmicroscalesamples.Byprovidingrobust,high-performancecoatings,Mo/FFPEcompositefilmsmaybeabletoprolongthelifespanandefficiencyofmicrofluidicdevices,whichcouldultimat