外文翻译--影响工件表面质量的因素.doc

英文原文InfluencefactorsonthequalityoftheworkpiecesurfaceProcessingprocessonthesurfacequalityoftheinfluenceThevibrationoftheprocesssystemoftheinfluenceonthequalityofthesurfaceInmechanicalprocessingprocesstechnologysystemsometimesoccurvibration,thatis,inthecuttingedgetoolandworkpieceiscuttingsurfaceexceptonthenamebetweencuttingmotion,butalsocanappearacyclicalrelativemotion.Vibrationthatprocesssystembyformingmovementoftheinterferenceanddamage,makeprocessingsurfaceappearchattermarks,increasesthesurfaceroughnessvalue,worseningprocessingsurfacequality.Cuttergeometricalparameters,materialsandcuttingqualitytothesurfacequalityoftheinfluenceThecuttingtoolgeometricparametersonthesurfaceroughnessofthebiggestinfluenceisvicePianJiao,themainpointPianJiao,arcradius.Undercertainconditions,reducePianJiao,Lord,vicePianJiaopointarcradiuscanreducesurfaceroughness.Underthesameconditions,carbidecuttingtoolsprocessofsurfaceroughnessvaluelessthanhighspeedsteelpapercuttingknife,anddiamondandCBN)toolsandbetterthanhardalloy,butbecausethediamondandironfamilyaffinitymaterials,itshouldnotbeusedforprocessingironfamilymaterials.Inaddition,thecuttingtoolbeforeandaftertheface,cuttingknifebladeitselfdirectlyinfluencetheroughnessoftheprocessingtheroughnessofthesurface,therefore,improvethequalityofcuttingtool,cuttingtoolandface,cuttingknifebladeroughnessvalueshouldbelowerthantheroughnessofthe12levels.CuttingfluidtotheinfluenceonthequalityofthesurfaceCuttingfluidcoolingandlubricationeffectcanreducethecuttingprocessofinterfacefriction,reducethetemperatureofcuttingzone,thecuttingmetalsurfacelayerofplasticdeformationdegreedown,restrainthedevelopthethornandscalesproducedintheproductionofdifferentmaterialsforreasonablechoiceofcuttingfluidscanreducethesurfaceroughness.TheworkpiecematerialonthesurfacequalityoftheinfluenceTheworkpiecematerialnature；Processingplasticmaterials,thecuttingtoolsformetalextrusionproducedplasticdeformation,andthecuttingtoolandworkpieceforcedseparationofthetornscrapseffect,makethesurfaceroughnessvalueincrease.Theworkpiecematerialtenacitythebetter,metal,plasticdeformation,thebiggertheprocessingsurfaceisthemoretherough.Processingbrittlematerialinthechipbrokengranular,duetothecollapseinbrokenandendowsthemachinedsurfaceleftmanypittedsurfaceroughness.Generaltoughnesslargeplasticmaterials,processingafterlargesurfaceroughness,andtoughnessofsmallerplasticmaterials,processingtogetsmallerafterthesurfaceroughness.Forthesamekindofmaterial,thegreaterthegrainsizeoftheorganization,thelargerthesurfaceroughness.Therefore,inordertoreducethesurfaceroughness,oftenincuttingprocessingofmaterialbeforequenchingandtemperingoristhefireoftreatmenttoobtainhomogeneousfinegrainorganizationandhighhardness.CuttingconditiontheinfluenceonthequalityofthesurfaceAndcuttingconditionoftherelevantprocessfactors,includingcuttingdosages,coolinglubrication.Inlowspeedprocessingplasticmaterials,easytoproducethedevolopandscalesthorn,so,improvethecuttingspeed,canreducethedevolopandscalesthorn,decreasingpartalreadythesurfaceroughnessvalue；Forbrittlematerial,generalwontformthedevolopandscalesthorn,so,cuttingspeedonthesurfaceroughnessbasicallynoinfluence.Theincreasespeed,plasticdeformationalsoincreases,thesurfaceroughnessincreases,so,reducethespeedcanreducethesurfaceroughnessvalue,however,feedingreducedtocertainvalue,roughnesswontobviouslydecreased.Normalcuttingconditions,cuttingdepthonthesurfaceroughnesstheimpactisnotbig,therefore,mechanicalprocesscannotselectthetoosmallcuttingdepth.CuttingspeedonthesurfaceroughnessinfluenceGeneralattheearlychooselowspeedcuttingandfinishingchoosehighspeedcuttingcanreducethesurfaceroughness.Inthemediumspeedcuttingplasticmaterials,duetoeasytoproducethedevolop,andplasticdeformationisbigger,soafterprocessingpartssurfaceroughnessisbigger.Usuallybyloworhighspeedcuttingplasticmaterial,caneffectivelyavoidthedevolopofgeneration,thistoreducetableandroughnesshavepositiverole.OnthesurfacequalityofthegrindingeffectsTheinfluenceofthegrindingwheelgrindingwheelgranularitythethinner,perunitareagrainnumbergrinding,themoreofthegrindingsurfaceinfinescratchesthesurfaceroughnessissmall；Butiftoofinegranularity,processingtojamwheelitwillincreasethesurfaceroughness,alsoeasytoproducetherippleandcauseburns.Thehardnessofthegrindingwheelshouldbetherightsize,itshalfthelongerthebetterpassivationperiod；Thehardnessofthegrindingwheelistoohigh,grindingmillisnoteasytofalloffwhengrain,makeprocessingsurfaceisoffriction,extrusionactionintensifies,thusincreasingtheplasticdeformation,makingthesurfaceroughnessincreases,alsoeasycauseburns；Butthegrindingwheelistoosoft,gritstooeasytofalloff,canmakegrindingactionisreduced,leadingtothesurfaceroughnessincreases,sotoselecttherightgrindingwheelhardness.Grindingwheeldressingthehigherthequality,thesurfaceofthegrindingwheelcuttingtheblade,cuttingthenumberofallthemorethebetterofthebladecontoursex,grindingsurfaceroughnessandsmaller.Theinfluenceofthegrindingwheelspeedincreasedosage,unittimethroughtheprocessingofgrindingsurfacegrainnumberincrease,eachstargritsisgroundtoreducethicknessofthemetal,thesurfaceareaoftheresidualreduced；Andatthesametime,improvethegrindingwheelspeedcanalsoreducetheworkpiecematerialofplasticdeformation,thesecanmakeprocessingsurfaceroughnessvaluereduced.Reducethespeed,unittimethroughtheprocessingofgrindingsurfacegrainnumberincrease,thesurfaceroughnessdecreased；Butthelowspeed,workpieceandgrindingwheelcontacttimelong,tothequantityofheatoftheincreasing,oppositewillincreasetheroughness,mayalsoincreasesurfaceburn.Increasegrindingdepthandlongitudinalfeeding,theplasticdeformationincrease,willleadtothesurfaceroughnessvalueincrease.Radialfeedingincrease,thegrindingprocessgrindingforceandgrindingtemperaturewillincrease,grindingsurfaceplasticdeformationdegreeincrease,whichwillincreasethesurfaceroughness.Toguaranteethemachiningqualityinthepremiseofgrindingefficiencyincrease,willrequireahighersurfacethecoarsegrindingandfinegrindingseparately,coarsegrindingisusedwhenthebigradialdirectionfeeding,finegrindingtheradialfeedingthesmallerwhen,finallywithoutintotogrinding,togetthesurfaceroughnessofsurfaceisverysmall.Theworkpiecematerialtheworkpiecematerialofhardness,plasticandthermalconductivityonthesurfaceroughnessofbigeffect.Largeplasticsoftmaterialeasyjamgrindingwheel,thermalconductivitypoorheatresistantalloyeasyfortheabrasiveearlycaving,willleadtoincreasedgrindingsurfaceroughness.Inaddition,becausegrindingtothehightemperature,reasonableusecuttingfluidscanreducethegrindingoftemperature,reduceburns,canalsorushedtofalloffthegritsandscraps,avoidscratchworkpiece,soastoreducethesurfaceroughness.AffectthesurfaceofphysicalandmechanicalpropertiesoffactorsSurfacelayercoldhardening.Thecuttingedgesobtuseradiusincreased,andthesurfaceofmetaltheextrusionofenhanced,plasticdeformationintensifies,coldhardtostrengthen.Aftercuttingtoolknifesurfacewearincreases,theknifesurfaceandafterprocessedsurfacefrictionintensified,plasticdeformationincrease,coldhardtostrengthen.Cuttingspeedincrease,cuttingtoolandworkpieceroletimeisshortened,makeplasticdeformationexpandthedepthdecreases,andcoldhardlayerdepthdecreases.Aftercuttingspeedincrease,heatcuttinginthesurfacelayereffecttimealsoshortened,willmakecoldharddegreeincrease.Feedingincreases,cuttingforcealsoincreased,andthesurfaceofthemetalplasticdeformationintensifies,coldhardeffectisstrengthening.Theworkpiecematerialofplasticislargerandthecoldhardphenomenontheserious.Surfacelayermaterialmetallographiccompositionchange.Whencuttingtheheatwasprocessingsurfacetemperatureofphasechangeaftermorethantemperature,thesurfaceofthemetalmicrostructurewillchange.Grindingburnswhenasurfacetemperatureofphasechangetomillerstemperatureabove,metalsurfacemicrostructureoccurredchange,makethesurfaceofthemetalstrengthandhardnessofthelower,andwithresidualstressproduceappearevenmicroscopiccracks,thisphenomenoniscalledgrindingburns.Improvegrindingburnsgrindingheatcausedbygrindingwayistherootoftheburn,soimprovinggrindingburnsbytwoways:oneisasfaraspossibletoreducethegenerationofgrindingheat；2itisimprovedcoolingcondition,makeasfaraspossiblethequantityofheattoproducelessworkpiece.Thecorrectchoicegrindingwheelreasonablechoiceofcuttingdosagesimprovedcoolingconditions.Surfacelayerresidualstress.Produceresidualstressofreason:cuttinginprocessingthemetallayerandthesurfacewhentherewereplasticdeformationoccurs,thesurfaceofthemetaltohematocritincrease；Cuttingprocessing,cuttingareawillhavealotofheatcuttingproduce；Differentanalysisofmetallographicorganizationhasdifferentdensity,alsohavedifferentolumeisnecessarilyaffectedbythechangeofconnectedthematrixofthemetalbar,henceresidualstressproduce.Themainworksurfaceeventuallyprocesstothechoiceofmethods.Choosethemainpartsworksurfaceeventuallyprocessmethod,wemustconsiderthemainpartsofthespecificworksurfaceworkingconditionsandthepossibledamagetotheform.Inalternatingload,themachinepartsonthesurfaceofthelocalmicrocracks,becauseoftensilestressofactiontomakeprimarycrackexpanding,resultinginpartsfracture.Improvepartsfromtheviewpointoffatiguedamageresistance,thefinalprocessshouldchoosethesurfaceinthesurfaceproducesresidualstressprocessingmethod.Inthemachiningprocess,toolsonthesquashandfrictionmakemetalmaterialshappenplasticdeformation,causetheoriginalresidueareaofdistortionorgroovelinesdeepened,increasesthesurfaceroughness.Whenthemediumormediumlowcuttingspeedcuttingplasticmaterial,thesurfacebeforetheswordineasytoformahighhardnessofthedevolop,itcantaketheplaceofthecuttingtool,butstateveryunstable,thedevolopgeneration,growupandfalloffwillseriouslyaffectthemachinedsurfaceroughnessvalue.Inaddition,incuttingprocessduetothestrongscrapsandformerknifefrictionroleandtearphenomenon,butalsoinprocessingonthesurfacemayproducescalethorn,makeprocessingsurfaceroughnessincreases.GrindingsurfacelayeranalysisofmetallographicorganizationchangesandgrindingburnsMechanicalprocessingproducesintheprocessofheatcuttingprocessingsurfaceofworkpiecewillmaketheriseoftemperatureoftheviolently,whenthetemperaturemorethantheworkpiecematerialmetallographicorganizationchangesofthecriticaltemperature,metallographicorganizationchangewilloccur.Ingrindingprocessing,becausemostgritsbeforecuttingAngleisnegative,grindingtemperatureishigh,thequantityofheatofgenerationismuchhigherthancuttingcaloriesat,andgrindingheathave60to80%totheworkpiece,soverypronetothechangeofmetallographicorganization,makesthemetalsurfacehardnessandstrengthofdecline,produceresidualstressandevencausemicrocracks,thisphenomenoniscalledgrindingburns.Producegrindingburns,processingsurfaceoftenappearyellow,brown,purple,greenandburncolor,thisisgrindingsurfaceoxidationofhightemperatureininstantaneousfilmundercolor.Differentburnscolor,showsthatthesurfaceofdifferentlevelsbyburns.Grindinghardenedsteel,workpiecesurfacelayerduetotheroleoftheinstantaneousheat,itmayproducethefollowingthreemetallographicorganizationchanges:Ifgrindingsurfacelayertemperaturenotoverphasetransitiontemperature,butmorethanmartensitetransitiontemperature,thenmartensitewillchangetobecomelowhardnessof