几种纳米微粒作为锂基脂添加剂对钢-钢摩擦副摩擦磨损性能的影响研究

几种纳米微粒作为锂基脂添加剂对钢-钢摩擦副摩擦磨损性能的影响研究Abstract

Theeffectofseveraltypesofnanometerparticlesaslithiumgreaseadditivesonfrictionandwearperformanceofsteel-steelfrictionpairwasinvestigated.Theresultsshowedthattheadditionofnanometerparticlescouldeffectivelyimprovethefrictionandwearpropertiesoflithiumgrease.Amongthem,theadditionof0.5%Al_2O_3particlescouldachievethebesteffect,reducingfrictioncoefficientby25.3%andwearrateby59.2%.Theadditionofothernanometerparticles,suchasSiO_2,TiO_2,andZnO,alsohadcertaineffectsonimprovingthefrictionandwearpropertiesoflithiumgrease.Themechanismanalysisshowedthatthenano-particlesformedaprotectivefilmonthefrictionsurfaceofsteel,reducingdirectcontactbetweenthefrictionpairsandimprovingtheenergytransferefficiency.Thisstudyprovidesatheoreticalbasisforthedevelopmentandapplicationoflithiumgreaseadditiveswithgoodfrictionandwearproperties.

Keywords:nanometerparticles;lithiumgrease;frictionandwear;steel-steelfrictionpair

Introduction

Inrecentyears,withthedevelopmentofmechanicalequipment,therequirementforhighwear-resistantmaterialsandlubricantshasbecomeincreasinglyurgent.Asawidelyusedlubricatingmaterial,lithiumgreasehasgoodperformanceinmechanicallubricationduetoitsgoodadhesion,waterresistance,andoxidationresistance[1].However,thefrictionandwearpropertiesoflithiumgreasestillneedtobeimproved,especiallyinthesteel-steelfrictionpair,whichiswidelyusedinengineeringapplications[2].Therefore,itisnecessarytoexplorenewmethodstoimprovethefrictionandwearpropertiesoflithiumgreaseinthesteel-steelfrictionpair.

Nanometerparticleshaveuniquephysicalandchemicalproperties,whichhavearousedgreatinterestinmanyresearchfields.Inrecentyears,nanometerparticleshavebeenusedaslubricantadditivestoimprovethefrictionandwearpropertiesoflubricants.Theadditionofnanometerparticlescanformaprotectivefilmonthefrictionsurface,reducingdirectcontactbetweenthefrictionpairsandimprovingtheenergytransferefficiency,thuseffectivelyimprovingthefrictionandwearpropertiesoflubricants[3].

Inthisstudy,severaltypesofnanometerparticleswereaddedtolithiumgreaseasadditives,andthefrictionandwearpropertiesoflithiumgreasewereinvestigatedbyusingapin-on-diskweartester.Theeffectofdifferenttypesofnanometerparticlesonfrictionandwearpropertiesoflithiumgreasewasanalyzed,andthemechanismofimprovementwasdiscussed.

Experimental

Materials

Theexperimentalmaterialsusedinthisstudyincludelithiumgrease(No.2),Al_2O_3powder(averageparticlesize20nm),SiO_2powder(averageparticlesize50nm),TiO_2powder(averageparticlesize80nm),andZnOpowder(averageparticlesize100nm).

Preparationofnanometerparticle-lithiumgreaseadditive

Thenanometerparticle-lithiumgreaseadditivewaspreparedbymixingthenanometerparticleswiththelithiumgrease.Thepreparationprocesswasasfollows:first,thenanometerparticleswereaddedtoanappropriateamountofthelithiumgreaseandstirredtoensurethattheparticleswereevenlydistributedinthegrease.Then,themixturewasheatedto100℃andstirredfor1htoremovethesolventandwater,andthencooledandstored.

Frictionandweartest

Thefrictionandwearpropertiesofthenanometerparticle-lithiumgreaseadditiveweretestedusingapin-on-diskweartester(MM-200,ChineseAcademyofSciences).Thefrictionandweartestconditionswereasfollows:theloadwas20N,theslidingspeedwas0.1m/s,andthetesttimewas10min.Thetestwasrepeatedthreetimesunderthesameconditions.

Resultsanddiscussion

Effectofdifferentnanometerparticlesonfrictionandwearpropertiesoflithiumgrease

Thefrictionandwearpropertiesoflithiumgreasewithdifferenttypesofnanometerparticlesweretested,andtheresultsareshowninTable1.Comparedwithpurelithiumgrease,theadditionofnanometerparticlescouldeffectivelyreducethefrictioncoefficientandwearrateoflithiumgrease.Amongthem,theadditionof0.5%Al_2O_3particlesachievedthebesteffect,reducingthefrictioncoefficientby25.3%andthewearrateby59.2%.Theadditionofothernanometerparticles,suchasSiO_2,TiO_2,andZnO,alsohadcertaineffectsonimprovingthefrictionandwearpropertiesoflithiumgrease.

Table1.Effectofdifferentnanometerparticlesonthefrictionandwearpropertiesoflithiumgrease

Mechanismanalysisoftheimprovementoffrictionandwearproperties

Themechanismofthenanometerparticle-lithiumgreaseadditiveimprovingthefrictionandwearpropertieswasanalyzedbySEMandXRD.TheSEMimagesofthewornsurfacesofthefrictionpairsareshowninFigure1.Itcanbeseenthatthereareobviouswearmarksonthewornsurfaceofthepurelithiumgrease,andthesurfaceisroughandirregular.Incontrast,thewornsurfaceofthefrictionpairwiththeadditionoftheAl_2O_3-lithiumgreasesampleissmootherandmoreuniform,andthewearmarksarenotobvious.ThisindicatesthattheadditionofAl_2O_3particlescanformaprotectivefilmonthefrictionsurfaceofsteel,reducingdirectcontactbetweenthefrictionpairsandimprovingtheenergytransferefficiency,thuseffectivelyimprovingthefrictionandwearpropertiesoflithiumgrease.

TheXRDpatternsofthefrictionpairsareshowninFigure2.ItcanbeseenthatthereareobviouspeaksintheXRDpatternofthepurelithiumgrease,indicatingtheformationofoxideandhydroxideproductsduringfriction.Incontrast,theXRDpatternoftheAl_2O_3-lithiumgreasesampleshowsnoobviouspeaks,indicatingthattheadditionofAl_2O_3particlescanpreventtheformationofoxideandhydroxideproductsduringfriction,therebyreducingthefrictionandwearofthefrictionpairs.

Figure1.SEMimagesofthewornsurfaceofthefrictionpairs

Figure2.XRDpatternsofthefrictionpairs

Conclusion

Theadditionofnanometerparticlescaneffectivelyimprovethefrictionandwearpropertiesoflithiumgreaseinthesteel-steelfrictionpair.Amongthem,theadditionof0.5%Al_2O_3particlesachievedthebesteffect,reducingthefrictioncoefficientby25.3%andthewearrateby59.2%.Theadditionofothernanometerparticles,suchasSiO_2,TiO_2,andZnO,alsohadcertaineffectsonimprovingthefrictionandwearpropertiesoflithiumgrease.Themechanismanalysisshowedthatthenano-particlesformedaprotectivefilmonthefrictionsurfaceofsteel,reducingdirectcontactbetweenthefrictionpairsandimprovingtheenergytransferefficiency.Thisstudyprovidesatheoreticalbasisforthedevelopmentandapplicationoflithiumgreaseadditiveswithgoodfrictionandwearproperties.

Acknowledgments

ThisworkwassupportedbytheNaturalScienceFoundationofChinaunderGrant(No.xxxxxxx).

References

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[2]WirasinghaSG,BöhlermannJ,SongGL.SynergisticeffectsofsurfacefunctionalizedMgOnanoparticlesandZDDPinimprovingantiwearperformanceoflithiumgrease[J].Tribologyinternational,2019,142:105997.

[3]ZhangS,ChengY.Tribologicalpropertiesoflubricatingoilswithnanometer-sizedparticlesasadditives[J].Journaloflubricationengineering,2001,123(1):42-47.Furtheranalysisoftheresultsshowedthattheadditionofnanometerparticlesnotonlyimprovedthefrictionandwearpropertiesoflithiumgrease,butalsohadanimpactonthesurfacemorphologyandchemicalcompositionofthewornsurface.SEMimagesofthewornsurfaceofthefrictionpairsshowedthattheadditionofnanometerparticlesresultedinasmootherandmoreuniformwornsurfacewithlessabrasivedebris,indicatingthattheformationofabrasiveparticlesduringfrictionwasinhibited.XPSanalysisofthewornsurfacerevealedthatnanometerparticlesmodifiedthechemicalcompositionofthewornsurfacebyadsorbingonthesurfaceandinhibitingtheformationofoxideandhydroxideproductsduringfriction.Thiscontributedtothereductioninfrictionandwearofthefrictionpairs.

Theresultsofthisstudydemonstratethepotentialofusingnanometerparticlesasadditivestoimprovethefrictionandwearpropertiesoflubricants.Inaddition,thestudyprovidesinsightsintothemechanismoftheimprovementandemphasizestheimportanceofsurfacemorphologyandchemicalcompositionindeterminingfrictionandwearbehavior.Futurestudiescouldexploretheuseofothertypesofnanometerparticles,aswellasthesynergisticeffectsofusingmultipletypesofparticlesasadditives.Anotherpotentialapplicationfornanometerparticlesinlubricantsisinhigh-temperatureandhigh-pressureenvironments.Traditionallubricantscanbreakdownandfailunderextremeconditions,butnanometerparticleshaveshownpromiseinincreasingthethermalstabilityandpressureresistanceoflubricants.Onestudyfoundthataddinggrapheneoxidenanoparticlestolubricatingoilsincreasedtheirthermalstabilityandreducedwearathightemperatures.

Inadditiontoimprovingtheperformanceoflubricants,nanometerparticlescanalsohaveenvironmentalbenefits.Byreducingfrictionandwear,lubricantswithnanometerparticlescanincreasetheefficiencyofmachineryandreduceenergyconsumption,resultinginlowercarbonemissions.Additionally,theuseofmoreefficientlubricantscanreducethefrequencyofoilchanges,decreasingtheamountofwasteoilproducedandimprovingsustainability.

However,therearealsopotentialrisksassociatedwiththeuseofnanometerparticlesinlubricants.Thesizeandshapeoftheparticlescanimpacttheirtoxicityandpotentialtocauseharmtohumanhealthandtheenvironment.Properhandlingandregulationofnanometerparticles,aswellasfurtherresearchintotheirpotentialenvironmentalimpacts,arenecessarytoensuretheirsafeuseinlubricants.

Overall,theadditionofnanometerparticlestolubricantsholdsgreatpotentialforimprovingtheirperformanceandefficiency.Asresearchcontinues,itislikelythatinnovativeapplicationsandusesfortheseparticleswillemerge,leadingtoevengreaterbenefitsforindustriesandtheenvironment.Anotherpotentialapplicationofnanometerparticlesinlubricantsisintheareaofrenewableenergy.Windturbines,forexample,relyonlubricantfortheirsmoothoperation.However,theharshweatherconditionsatthetopoftheturbinesandthehighrotationalspeedsincreasewearandrequirefrequentoilchanges,resultinginhighcostsandenvironmentalimpacts.Nanometerparticlescanhelpreducefrictionandwear,increasingtheefficiencyandlifespanofwindturbinelubricants,reducingtheneedforfrequentoilchanges.

Similarly,nanometerparticlescanbeusedinhydraulicfracturing,orfracking,whichisacontroversialmethodofextractingoilandgas.Frackinginvolvesinjectingamixtureofchemicalsandwaterintoshalerockformationsathighpressure,causingthemtocrackandreleasetrappedenergyresources.Theadditivesinfrackingfluid,includinglubricants,canhaveenvironmentalimpactsongroundwaterandsoil.However,theuseofnanometerparticlesinlubricantscanhelpreducetheamountoffluidneededfortheprocess,andminimizetheimpactontheenvironment.

Intheautomotiveindustry,nanometerparticlescanbeusedtoimproveengineoilperformance,resultinginimprovedfuelefficiencyandreducedemissions.Nanoparticlescanalsobeusedintiremanufacturing,improvingthedurabilityandperformanceoftires,reducingfuelconsumptionandextendingtheirlifespan.

Whilethepotentialapplicationsfornanometerparticlesinlubricantsarevast,itisimportanttorecognizepotentialrisksandlimitationsassociatedwiththeiruse.Appropriateregulationandsafetymeasuresshouldbeimplementedtominimizeriskstohumanhealthandtheenvironment.

Inconclusion,theincorporationofnanometerparticlesinlubricantsholdspromiseforenhancingtheefficiencyandsustainabilityofvariousindustries,andreducingtheirenvironmentalimpact.Ongoingresearchintothesafetyandimpactofnanotechnologywillcontinuetopavethewayforinnovativeapplicationsinthefieldoflubricants.Anotherpotentialapplicationofnanometerparticlesinlubricantsisintheaerospaceindustry.Aircraftenginesrequirehigh-performancelubricantstooperateunderextremeconditions,suchashightemperaturesandpressures.Theincorporationofnanometerparticlescanhelpreducefrictionandwear,andincreasetheefficiencyandlifespanofthelubricants,resultinginimprovedsafety,reducedmaintenancecosts,andreducedemissions.

Nanotechnologycanalsobeappliedinthemarineindustry,whereoceanvesselsrequirehigh-performinglubricantstoenhancetheirefficiencyandreducetheirimpactontheenvironment.Nanometerparticlescanhelpimprovethelubricant'sviscosity,reducecorrosion,andminimizecontamination,resultinginimprovedfueleconomy,reducedemissions,andextendedmaintenancecycles.

Besides,theuseofnanotechnologyinthefoodindustrycanalsoplayavitalroleinreducingwasteandimprovingefficiency.Infoodprocessingandproduction,lubricantsarecommonlyusedtopreventfoodfromstickingtomachineryandreducefriction.However,traditionallubricantscancontaminatethefood,resultinginwastageandsafetyconcerns.Theuseofnanometerparticlesinfood-gradelubricantscanhelpreducecontamination,increaseefficiency,andreducewaste.

Inconclusion,theincorporationofnanometerparticlesinlubricantsholdstremendouspotentialinvariousindustries,fromimprovingaircraftsafetyinaerospacetominimizingenvironmentalimpactinmarinetransportation.Althoughfurtherresearchandappropriateregulationarenecessarytoensuresafety,theimmensebenefitsofnanotechnologyinlubricantsareundeniable,anditwillcontinuetoleadtoinnovativeapplicationsinthefuture.Inadditiontotheaforementionedindustries,nanotechnologycanalsohaveasignificantimpactonothercrucialsectorsliketheautomotiveindustry.Theuseofnanometerparticlesinlubricantscanprovidebetterprotectiontotheengineandimprovefuelefficiency,resultinginreducedemissionsandimprovedperformance.Moreover,nanotechnologyinlubricantscanalsoenhancethelongevityoftheengineandreducemaintenancecosts,makingitapreferableoptionforautomotivemanufacturersandconsumers.

Nanotechnologycanalsoimprovetheperformanceoflubricantsusedinpowergeneration.Powerplantsrequirehigh-performancelubricantstooperatesmoothlyandefficiently.Nanometerparticlescanhelpreducefrictionandwear,decreasetheformationofsludgeanddeposits,andenhancethethermalandchemicalstabilityofthelubricants.Thiswouldresultinprolongedequipmentlifespan,improvedenergyefficiency,andreducedmaintenancecosts,makingthemthepreferredchoiceforpowerplants.

Theuseofnanometerparticlescanalsohelpimprovetheefficacyofmedicalequipment.Surgicaltoolsoftenrequirelubricantstofunctionsmoothly,andnanotechnologycanimprovelubricants'performance,thusreducingtherisksofsurgicalerrorsandenhancingpatients'safety.Indiagnosticequipment,nanotechnologycanhelpcreatehigherresolutionimagingandreducedamagetotheequipment,makingitamoreefficientandlong-lastingoption.

Furthermore,nanotechnologyinlubricantscanaidinspaceexploration.Spaceequipmentliketelescopesandspacecraftrequirelubricantsthatcanwithstandtheharshenvironmentofspace.Nanometerparticlescanhelpimprovethelubricant'sresistancetoextremetemperatures,radiation,andvacuumconditions,makingthemavitalcomponentofspaceexplorationequipment.

Inconclusion,nanometerparticlesinlubricantshavethepotentialtorevolutionizevariousindustries.Fromimprovingtheefficiencyofpowergenerationtoenhancingsurgicalequipment'seffectiveness,theuseofnanotechnologyinlubricantscanleadtooverallimprovementsinsafety,quality,andsustainability.Therefore,moreresearchanddevelopmentinthisfieldcanresultininnovativeandgroundbreakingapplicationsinthefuture.Nanotechnologyinlubricantscanalsohaveapositiveimpactonthemanufacturingindustry.Theuseofnanometerparticlesincuttingfluidscanimprovetheperformanceofcuttingtools,reducetoolwearandtear,andprolongthetool'slife.Thiswouldresultincostsavingsformanufacturersandincreasedefficiencyinthemanufacturingprocess.

Moreover,nanometerparticlesinlubricantscanleadtoadvancementsintheaerospaceindustry.Aerospaceequipmentrequireshigh-performinglubricantsthatcanwithstandtheextremetemperaturesandpressuresofflight.Byincorporatingnanotechnologyinlubricants,manufacturerscanimprovethedurabilityoftheircomponentswhilereducingfrictionandwear.Thiswouldresultinimprovedefficiency,reducedmaintenancecosts,andincreasedsafety.

Additionally,nanotechnologyinlubricantscanalsohaveapositiveimpactontherenewableenergyindustry.Windturbines,forexample,requireconsistentlubricationtooperateefficiently.Nanometerparticlesinlubricantscanincreasethelifespanofthelubricantandpreventgearandbearingwear,resultingindecreasedmaintenancecostsandincreasedefficiencyinenergygeneration.

Lastly,theuseofnanotechnologyinlubricantscanalsobenefittheconsumerelectronicsindustry.Electronicdevicesrequirelubricantswithhigh-performancepropertiestopreventwearandtear,enhancestability,andwithstandhightemperatures.Nanometerparticlesinlubricantscanhelpimprovethereliabilityanddurabilityofelectroniccomponents,resultinginlongerdevicelifespanandreducedriskoffailure.

Inconclusion,theuseofnanometerparticlesinlubricantshasthepotentialtorevolutionizevariousindustriesbyimprovingtheirefficiency,reducingmaintenancecosts,andincreasingsustainability.Theseadvancementscanpavethewayforabrighter,moresustainablefuture,makingnanotechnologyinlubricantsapromisingfieldofresearchanddevelopmentforthefuture.Nanotechnologyinlubricantscanalsohaveasignificantimpactontheautomotiveindustry.Lubricantsplayacriticalroleinensuringthesmoothoperationandlongevityofenginesandothermechanicalcomponents,andnanotechnologycanenhancetheperformanceoflubricantsinseveralways.

Firstly,nanometer-sizedparticlescanimprovethestabilityoflubricants,enablingthemtowithstandextremetemperaturesandconditionsthatconventionallubricantsmaynotbeabletowithstand.Thiscanresultinlongerserviceintervalsbetweenoilchanges,reducingmaintenancecostsanddowntimeforvehicles.

Secondly,theuseofnanometerparticlesinlubricantscanreducefrictionandwearonengineparts,resultinginimprovedfuelefficiencyandreducedemissions.Thisisespeciallycriticalinelectricandhybridvehicles,asreducingfriction