外文翻譯--鍛造工藝不當(dāng)產(chǎn)生的缺陷.doc

Forgingcraftnotwhenproducesflaw1.Bigcrystalgrainhyperpyrexiaandthedistortiondegreeinsufficiency,ortheendhammersthehyperpyrexia,orthedistortiondegreefallsthehumancriticaldeformationrangetocause.Aluminumalloydistortiondegreeoversized,formsthetexture；Alsotheheat-resistingalloydistortiontemperatureexcessivelyislow,formswhenthemixdistortionorganizationpossiblycausesthethickcrystalgrain2.Thecrystalgrainisnon-uniformThecrystalgrainnon-uniformisreferstoforgingcertainspotsthecrystalgraintobespeciallythick,certainspotsareactuallysmall.Hasthecrystalgrainnon-uniformprimarycauseissemifinishedmaterialseachplacedistortioncausesthecrystalgrainstavedegreenon-uniformnotone,eitherthepartialregiondistortiondegreefallsthehumancriticaldeformationrange,eitherheat-resistingalloypartialworkhardening,eitherwhenquenchingheatingthepartialcrystalgrainisthick.High-temperaturesteelandheat-resistingalloytocrystalgrainnon-uniformspeciallysensitive.Thecrystalgrainnon-uniformwillcausetheforgingthelastingperformance,thewearyperformancetodropobviously.3.ChillingphenomenonWhendistortionbecausethetemperaturesomewhatloworthedistortionspeedtooisquick,aswellashammerstheafter-coolingexcessivelyquickly,possiblycausestheconditioningwhichtherecrystallizationcausesnottobeabletofollowthestrengtheningwhichthedistortioncauses(hardening),afterthuscausedthehotforgingtheforginginteriorstillthepartretentioncold-workorganization.Thiskindoforganizationsexistenceenhancedtheforgingintensityanddegreeofhardness,butreducedtheplasticityandtoughness.Theseriouschillingphenomenonpossiblycausestheforgingcrack,seesexample78,79,83,84.4.CrackThecrackisusuallywhenforginghasthebigtensilestress,theshearstressortheadditionaltensilestresscauses.Thecrackoccursthespotusuallyisbiggestinthesemifinishedmaterialsstress,thethicknessthinnestspot.Ifthesemifinishedmaterialssurfaceandtheinteriorhavethemicrocrack,orinthesemifinishedmaterialshavetheorganizationflaw,eitherhot-workingtemperaturenotwhencausesthematerialplasticitytoreduce,eitherdistortionspeedexcessivelyquickly,distortiondegreeoversized,surpassesthematerialpermissiontheplasticindicatorandsoon,theninremovesthick,pullsoutlong,thepunchholes,thebroaching,curvingandworkingproceduresandsooninextrusionallpossiblyproducesthecrack.5.ChapThechapispresentstheshallowturtleshapecrackintheforgingsurface.Intheforgingformingthetensionstresssurface(e.g.,fillhasnotprotrudedpartorcurvingpart)easiesttoproducethiskindofflaw.Causesthechapinternalcausepossiblyisvarious:RawmaterialgathersfusibleelementsandsoontheCu,Snexcessivelyaremany.Whenhightemperaturelongtimeheating,thesteelmaterialssurfacehasthecoppertoseparateoutthesurfacewhich,thesuperficialcrystalgrainthick,thedecarbonization,orpassesthroughheatsupmanytimes.Thefuelmeasuresincludingthesulfurexcessivelyhigh,hasthesulfurtoinfiltratethehumansteelmaterialssurface.6.EdgecrackTheedgecrackiswhenthedropforgingandthecuttingedgeproducesthecrackinaminutemodularsurfaceplace.Theedgecrackproducesthereasonpossiblyis:Indropforgingoperationbecausehitshardcausesthemetalintenseflowingtoproduceputsonthemusclephenomenon.Themagnesiumalloydieforgeditemcuttingedgetemperatureexcessivelyislow；Copperalloydieforgeditemcuttingedgehyperpyrexia.7.MinutemodularsurfacecrackTheminutemodularsurfacecrackreferstothecrackwhichproducesalongaforgingminutemodularsurface.Rawmaterialmixeswithnonmetallicmany,whendropforgingtodividesthemodularsurfaceflowingandthecentralismorthepiperemainingafterthedropforgingpushesthehumanedgeoftentheshapeingredientmodularsurfacecrack.8.FoldThefoldwasintheflowofmetalprocesshasoxidizedthesurfacelayermetalconvergedtoformtogether.Itmaybe(ormulti-stocks)themetalconvectionconvergenceformsbytwo；Alsomightbethemassiveflowingisclosetothepartrapidlybyametalthesurfacelayerstrapflowing,bothconvergencewillform；Alsomaybebecausethedistortionmetalhas,thebackflowcurvingforms；Alsomaybethepartialmetallocaldistortion,isoppressedothersinanotherpartofmetalstoform.Foldingandrawmaterialandsemifinishedmaterialsshape,molddesign,formedworkingprocedurearrangement,lubricationsituationandforgingactualoperationandsoonrelatedNotonlythefoldreducedthecomponentsloadbearingarea,whenworksbecauseherestressconcentrationoftenbecomesthewearysource9.PutsontheclassPutsontheclassisthestreamlinedistributestheimproperoneform.Isputtingonflowsthearea,hascertainangledistributionthestreamlinetoconvergeoriginallytoformtogetherputsontheclass,possiblyandcausestoputonflowstheareainsideandoutsidegrainsizedifferencetobedisparate.Putsonthereasonwhichtheclassproduceswiththefoldtobesimilar,isbytwometalsorstrap,butputsonflowsthepartwhichanothermetalaffluxesformthemetalstillwasawholeputsontheclasstocausetheforgingmechanicsperformancetoreduce,whenputsonespeciallyflowsthebeltbothsidescrystalgraindifferenceisdisparate,theperformancereducesobviously.10.TheforgingstreamlinedistributionisnotsuitableTheforgingstreamlinedistributionalongisnotrefersonforginglowtimehasstreamlinedisorderphenomenaandsoonstreamlinecut-off,backflow,turbulentflow.Ifthemolddesigndoesnotworkasortheforgingmethodchoiceisunreasonable,prefabricatedsemifinishedmaterialsstreamlinedisorder；Theworkerdoesnotoperatewhenandthemoldwearscausesthemetaltoproducethenon-uniformflowing,allmaycausetheforgingstreamlinedistributionnottobesuitable.Thestreamlinealongcannotcauseeachmechanicsperformancetoreduce,thereforeregardingtheimportantforging,allhastherequestwhichthestreamlinedistributes.11.ThecastingorganizationremainsThecastingorganizationremainsmainlyappearsinusestheingotcastingtomakethesemifinishedmaterialsintheforging.Thecastconditionorganizationmainlyremainsintheforgingdifficultdeformationrange.Forgingcomparedtoinsufficientandforgingmethodnotwhenistheprimarycausecastingorganizationwhichthecastingorganizationremainsproducesremainscancausetheforgingtheperformancedrop,attacksthetenacityandthewearyperformanceinparticularandsoon.12.CarbidesegregationranknotsymbolrequestThecarbidesegregationranksymbolrequestmainlydoesnotappearintheLaibodylabormoldingtoolsteel.Mainlyisintheforgingcarbidedistributesnon-uniform,assumesthegreatlymassivecentralismdistributionorassumesthenetteddistribution.Createsthiskindofflawtheprimarycauseisrawmaterialcarbidesegregationrankisbad,addsitchangeshammerswhenhammerscomparedtoinsufficientortheforgingmethodnotwhenhasthiskindofflawforging,whenheattreatmentquenchingeasypartialsuperheatandquenchesthecrack.Makesthecuttingtoolandthemoldusewheneasybreakingandsoon.13.BandedstructureThebandedstructureistheferriteandthepearlyte,theferriteandtheaustenite,theferriteandthebainiteaswellastheferriteandthemartensiteassumesthebelt-shapeddistributionintheforgingonekindoforganization,theyappearinAsiaaltogetherfoldinthesteel,theaustenitesteelandhalfmartensitesteel.Thiskindoforganization,iswhenwhichthebandedstructurewhichtwocoexistsinthesituationforgesdistortionproducestobeabletoreducethematerialthecrosswiseplasticindicator,speciallyresilience.Ofteniseasyinforgingeitherthecomponentsworkalongthelinesofferriteortwointersectionpointdehiscence.14.PartialbackfillinsufficiencyThepartialbackfillinsufficientmainlyoccursinthemusclerib,theconvexangle,thecorner,thefilletspot,thesizedoesnotconformtothepatternrequirement.Producesthereasonpossiblyis:Theforgingtemperatureislow,themetalfluidityisbad；Theequipmenttonnageinsufficientorthehammerstrengthisinsufficient；Thesystemmoldsthedesignnottobeunreasonable,thesemifinishedmaterialsvolumeorthesectionsizeareunqualified；Inthemoldchestcavitypilesuptheoxideskinortheweldedtogetherdistortionmetal.15.OwesthepressureOwesthepressuretoreferisverticalincreases,thereasontotheminutemodularsurfacedirectionsizewhichproducespossiblyisgenerally:Theforgingtemperatureislow.Theequipmenttonnageisinsufficient,hammerstrengthinsufficiencyorhammernumberoftimesinsufficient16.WrongmovesWrongmovesistheforgingisoppositealongtheminutemodularsurfaceupperhalfinthelowerparthasthedisplacement.Producesthereasonpossiblyis:Slide(hammerhead)andbetweenguiderailgapoversized；Theforgingdiedesignisunreasonable,lackseliminateswrongmovesthestrengthtocloseupanopeningortheguidepillar；Moldinstallmentnotgood17.ThespoolthreadiscurvingTheforgingspoolthreadiscurving,hastheerrorwiththeplanegeometryposition.Producesthereasonpossiblyis:Theforgingleaveswhenthemolddoesnotpayattention；Whencuttingedgethestressisuneven；Theforgingcoolswhenvariouspartoftemperaturedecreasespeednotone；Thecleaningupandtheheattreatmentimproper鍛造工藝不當(dāng)產(chǎn)生的缺陷1.大晶粒大晶粒通常是由于始鍛溫度過(guò)高和變形程度不足、或終鍛溫度過(guò)高、或變形程度落人臨界變形區(qū)引起的。鋁合金變形程度過(guò)大，形成織構(gòu)；高溫合金變形溫度過(guò)低，形成混合變形組織時(shí)也可能引起粗大晶粒2.晶粒不均勻晶粒不均勻是指鍛件某些部位的晶粒特別粗大，某些部位卻較小。產(chǎn)生晶粒不均勻的主要原因是坯料各處的變形不均勻使晶粒破碎程度不一，或局部區(qū)域的變形程度落人臨界變形區(qū)，或高溫合金局部加工硬化，或淬火加熱時(shí)局部晶粒粗大。耐熱鋼及高溫合金對(duì)晶粒不均勻特別敏感。晶粒不均勻?qū)⑹瑰懠某志眯阅?、疲勞性能明顯下降。3.冷硬現(xiàn)象變形時(shí)由于溫度偏低或變形速度太快，以及鍛后冷卻過(guò)快，均可能使再結(jié)晶引起的軟化跟不上變形引起的強(qiáng)化（硬化），從而使熱鍛后鍛件內(nèi)部仍部分保留冷變形組織。這種組織的存在提高了鍛件的強(qiáng)度和硬度，但降低了塑性和韌性。嚴(yán)重的冷硬現(xiàn)象可能引起鍛裂，