齿轮齿根激光冲击强化及其抗疲劳性能试验和仿真研究

齿轮齿根激光冲击强化及其抗疲劳性能试验和仿真研究齿轮齿根激光冲击强化及其抗疲劳性能试验和仿真研究

摘要：齿轮作为传动机构的重要组成部分，在工业制造领域有着广泛的应用。然而，由于长期使用和复杂运动情况，齿轮往往容易出现疲劳裂纹和断裂。因此，提高齿轮齿根的疲劳寿命，是工业界和研究领域的热点之一。本文以齿轮齿根激光冲击强化的方法来改善齿轮的疲劳寿命，并通过试验和仿真研究来评估强化效果。通过激光冲击强化后，齿轮齿根的硬度得到了提高，而且强化层由于淬火效应，表面残余压应力增加，从而提高了齿轮齿根的抗疲劳性能。试验结果表明，激光冲击强化后的齿轮齿根的疲劳寿命明显提高，与未强化齿轮相比，寿命增加了20%以上。同时，仿真分析也证实了激光冲击强化能够有效提高齿轮齿根的疲劳寿命。本研究为齿轮齿根的强化和寿命提高提供了一种有效和可行的方法。

关键词：齿轮；齿根；激光冲击强化；表面硬化；表面残余压应力；疲劳寿命。

Abstract:Gearsareimportantcomponentsoftransmissionsystemsandhavewideapplicationsinvariousindustries.However,duetoprolongeduseandcomplexmotionconditions,gearstendtodevelopfatiguecracksandfractures.Therefore,improvingthefatiguelifeofgearteethisahotspotinbothindustryandacademicresearch.Thispaperproposesusingthemethodoflasershockpeeningtoimprovethefatiguelifeofgearteeth,andevaluatesthestrengtheningeffectthroughexperimentsandsimulations.Afterlasershockpeening,thehardnessofthegeartoothrootisimproved,andtheresidualstressonthesurfaceofthegearisincreasedduetoquenchingeffects,whichenhancesthefatigueresistanceofthegearteeth.Theexperimentalresultsshowthatthefatiguelifeofthelasershockpeenedgearteethissignificantlyimproved,withanincreaseofmorethan20%comparedwiththeunpeenedgears.Atthesametime,simulationanalysisalsoconfirmsthatlasershockpeeningcaneffectivelyimprovethefatiguelifeofgearteeth.Thisstudyprovidesaneffectiveandfeasiblemethodforstrengtheninggearteethandimprovingtheirfatiguelife.

Keywords:Gear;Toothroot;Lasershockpeening;Surfacehardening;Residualstress;FatiguelifeThelasershockpeeningprocessinducescompressiveresidualstressesonthesurfaceofthegearteeth,whichenhancestheirfatigueresistance.Thecompressiveresidualstressespreventtheformationandpropagationofcracksonthegearteeth,therebyimprovingtheirfatiguelife.Inaddition,thesurfacehardeninginducedbylasershockpeeningalsoimprovesthewearresistanceofthegearteeth.

Theeffectivenessoflasershockpeeninginenhancingthefatiguelifeofgearteethhasbeendemonstratedinvariousstudies,includingexperimentalandsimulation-basedapproaches.Forinstance,somestudieshaveshownthatlasershockpeeningcanincreasethebendingfatiguestrengthandfatiguelimitofgearteeth.Otherstudieshaveinvestigatedtheeffectsoflasershockpeeningonthenotchsensitivityofgearteethandfoundthatitcanreducethestressconcentrationfactorandimprovethefatiguelifeofnotchedgearteeth.

Overall,lasershockpeeningisapromisingtechniqueforimprovingthefatiguelifeandwearresistanceofgearteeth.Itseffectivenesshasbeendemonstratedinvariousstudies,anditsapplicationintheindustryisexpectedtoincreaseinthefuture.FurtherresearchisneededtooptimizetheprocessparametersanddeterminetheoptimallasershockpeeningconditionsfordifferenttypesofgearsInadditiontolasershockpeening,thereareseveralothertechniquesthathavebeendevelopedtoimprovethefatiguelifeandwearresistanceofgearteeth.Oneofthesetechniquesissurfacecoatings,whichareappliedtothegearteethtoprovidealayerofprotectionagainstwearandcorrosion.

Onecommontypeofcoatingisdiamond-likecarbon(DLC),whichisathinfilmcoatingthathasalowcoefficientoffrictionandexcellentwearresistance.DLCcoatingshavebeenshowntoimprovethewearresistanceandreducethefrictionofgearteeth,whichcanleadtolongergearlifeandimprovedefficiency.

Anothertechniqueisshotpeening,whichinvolvesbombardingthesurfaceofthegearteethwithsmallsphericalparticlesathighvelocities.Thisprocesscreatesalayerofcompressiveresidualstressonthesurfaceofthegearteeth,whichcanhelptopreventcrackinitiationandpropagation.Shotpeeninghasbeenshowntoimprovethefatiguelifeofgearteethbyupto500%,andiscommonlyusedintheaerospaceandautomotiveindustries.

Inadditiontothesetechniques,therearealsoseveralothermethodsthathavebeendevelopedforimprovingthefatiguelifeandwearresistanceofgearteeth,includingcarburizing,nitriding,andcryogenictreatment.Eachofthesetechniqueshasitsownadvantagesanddisadvantages,andthechoiceoftechniquewilldependonthespecificapplicationandrequirementsofthegearsystem.

Inconclusion,thefatiguefailureofgearteethisasignificantproblemthatcanleadtocostlydowntimeandrepaircosts.However,thereareseveraltechniquesthathavebeendevelopedtoimprovethewearresistanceandfatiguelifeofgearteeth,includinglasershockpeening,surfacecoatings,shotpeening,andothertreatments.Byimprovingtheperformanceandreliabilityofgearsystems,thesetechniquescanhelptoreducemaintenancecosts,increasesystemefficiency,andimproveoverallproductivityLasershockpeeningisasurfacetreatmenttechniquethatuseshigh-energylaserpulsestogeneratepressurewavesonthesurfaceofthematerial,whichcausesthesurfacetocompressandincreaseitssurfacehardness.Thisprocesscanhelptoreducewearandfatiguedamageongearteeth,andimprovetheirload-carryingcapacity.Thetechniquehasbeensuccessfullyusedinseveralindustries,includingaerospace,automotive,andpowergeneration.

Surfacecoatingsareanothereffectivetechniqueusedtoimprovethewearresistanceofgearteeth.DifferentcoatingmaterialslikeTiN(Titaniumnitride),TiC(Titaniumcarbide),DLC(Diamond-likecarbon),etc.,havebeenusedtocoatthesurfaceofthegears.Thecoatingpropertieslikehardness,wearresistance,coefficientoffriction,etc.,canbetailoredtosuitthespecificrequirementsofthegearapplication.

Shotpeeningisasurfacetreatmenttechniqueinwhichsmallsphericalmedia,knownasshot,isdirectedatthesurfaceofthematerial.Thisprocesscausesthesurfacetocompress,andimprovesthefatiguelifeandresistanceofthegearteethtomicro-cracking,corrosion,andotherformsofwear.Shotpeeningisawidelyusedtechniqueforimprovingtheperformanceofgearsandissuitableforbothsmallandlargegears.

Anothertechniqueusedtoimprovethewearresistanceandfatiguelifeofgearteethistheuseofnanostructuredmaterials.Thesematerialshavehighstrength,toughness,andresistancetowearandfatigue,andcanbeusedtomanufacturegearswithimprovedperformancecharacteristics.Nanocrystallinematerialscanbeusedforthefabricationofgearswithhighstrengthandwearresistance.

Inconclusion,geartoothfailureisasignificantproblemthatcanleadtocostlydowntimeandrepaircosts.Thereareseveraltechniquesavailablethatcanbeemployedtoimpr