Die-Casting-Defects

压铸缺陷产生原因及解决方法DieCastingDefects–CausesandSolutions第一章表面缺陷ChapterOneSurfaceDefects--Thosedefectscommonlycalledcoldflowornon-fills.表面缺陷：冷纹、冷隔、激冷层、未充满、涡流纹等Surfacedefects:Coldflow,coldlap,chill,non-chill,swirls,etc.产生原因：金属液流前端温度太低，搭接在一起。MAINCAUSE：Metalisfrozenwhentwometalfrontsjoin.改善措施：Solutions:1.提高模具温度Increasemoldtemperature2.减少充型时间Shortenfeedingtime3.改变填充模式（内浇口）Changefeedingway（gate）4.核查降低金属液温度的原因Inspectwhatloweredthemetalmeltstemperature5.核查压射后期压力过低的原因Inspectwhatloweredtheinjectionpressureatthelatterphase6.储压器预置压力过低或者过高Thepressureoftheaccumulatorwassettoolowortohigh7.料饼太薄Materialcakesaretoothin8.飞边严重Severeflash第二章多层皮ChapterTwoLaminations--Defectsfromlayersofmetalformingduringtheprocess.多层皮：铸件表面或者内部有明显的多层金属皮Laminations：Layersofmetalinsideoroutsideofcasting产生原因：金属液流动不当等。MAINCAUSE：Metalmeltsflowsimproperlyduringtheprocess.改善措施：Solutions：1.检查压铸参数Inspecttheparameterofthediecastingmachine2.运用合适的金属流动模式—避免长距离的金属液流动，确保金属液不在离内浇口很远处汇合。Usetherightmetalflowingways,trytoavoidlongdistancemetalflowing,andmakesurethatthemetalmeltsdoesn’tjointoofarawayfromthegate.3.调节合适的模具温度，使问题区域的模具温度均匀，最好温度稍高。Adjustthetemperatureofthemold;makesurethatthetemperatureofthetargetareaiswell-distributedorhigherthanitshouldbe.4.合适的增压过程，增压过程要平稳Stabilizetheprocessofthepressureincreasing5.模具不应该变形（模具可能在增压挠曲—核查模具是否有足够的支撑）Makesurethattheshapeofthemolddoesn’tchangewiththeincreasingofthepressure;inspectifthemoldisstrongenoughtokeepitsshapewiththeincreasingofthepressure.第三章气孔ChapterthreeGasPorosity--Internalporosityfromtrappedgasofvariouskinds.缺陷：气孔Gasporosity产生原因：在充型的过程中气体卷入金属液流而形成的。MAINCAUSE:Inthefeedingprocess,gasporosityisformedfromthegasdrawnintothemetalmeltsflow.改善措施：Solutions:1.气体来自于卷入空气、水蒸气或者模具润滑剂产生的气体-核查卷入气体的来源。Inspectthewayshowgasisdrawnintothemetalmeltsfloworinspectwhetherthegasisfromtheair,thesteam,themoldlubricantetc.2.核查内浇道以保证金属液平稳流动。Inspectthegatetomakesurethesteadyflowofmetalmelts.3.检查排气孔。Inspecttheexhaustvent.4.保证真空系统正常工作。Assuretheproperfunctioningofvacuumsystem5.核查来自于润滑剂的气体。Inspectthegasfromthemoldlubricant.6.核查水汽（模具上的水）Inspectthewatervapor,especiallythewaterinthemold.第四章气泡ChapterfourBlisters--Surfacemanifestationoftrappedgas.缺陷：气泡（Blisters）产生原因：在充型的过程中卷入金属液的气体在铸件表皮下形成的泡。MAINCAUSE:Inthefeedingprocess,blistersareformedfrom改善措施：MAINCAUSE:1.气泡是气孔的另外一种表现形式，因此，针对气孔的改善措施同样也使用与气泡。如：减少卷入空气或改善排气和真空系统问题。Blisterisjustanotherformofgasporosity.Therefore,itssolutionsaresimilartothoseofgasporosity.Forexample,wecandecreasethegasfromtheairorbettertheexhaustventandvacuumsystem.2.解决气泡问题最根本方法时解决气孔问题，然而，作为一种暂时性的解决方法，可通过喷雾冷却产生气泡的部位。Theessentialsolutionistosolvetheshrinkageporosityproblem.However,asatemporarysolution,wecancooldownthetargetareabymistspray.3.取出铸件后立刻猝水冷却（这种方式可以提高铸件表面强度从而阻止气泡形成）。Cooldownthecastingsimmediatelyaftertakingout,whichcanimprovetheintensityofthecastingsurfaceandpreventblisters.4.降低金属液温度（但应注意是否产生其他问题）Lowerthemetalmeltstemperatureandpayattentiontheothersproblemsitwillproduce.第五章流体间隙Chapter5FlowPorosity--Surfaceorinternalporosityfrompoorpressureconditions流体间隙Flowporosity产生原因MAINCAUSE金属液流动过慢，温度过低或者流动模式不当，在凝固的金属液流之间产生间隙（孔洞）。Surfaceorinternalporositycausedbypoorflowingconditionsorlowtemperaturesofthemetalmelts.改善措施Solutions1.流体间隙是一种金属液流动产生的缺陷，所以前面提到的解决表面缺陷的改善措施也适用于改善流体间隙的缺陷Flowporosityisadefectthatcausedbypoorflowingconditionsofthemetalmelts.Sothesolutionsforthesurfacedefectscanalsobeappliedtosolveflowporosity.2.金属液之间的间隙可能出现在铸件的表面（空穴），也可能存在于铸件的内部（孔洞），稳定熔炉操作（降低炉温的波动，最大波动应该小于+/-5.6°C），采用修正后的金属温度Thegapsoccurredduringtheprocessofdiecastingcanbeonthesurfaceofthecasting,whicharecalledcavitations,orinsideofthecasting,whicharecalledholes.Stabilizethetemperatureofthefurnace,keeptherighttemperatureandkeepthetolerancetobewithin+/-5.6°C.3.稳定模具温度，采取较高的模具温度（大于204.4°C）Stabilizethetemperatureofthemold,andusearelativelyhighertemperature(higherthan204.4°C)forthemold.4.检查并修正金属液压力Inspectandadjustthepressureofthemetalmelts.第六章缩松、缩孔ChaptersixShrinkPorosity--Porosityfromthevolumechangeasthemetalchangesstate.缺陷：缩松Shrinkageporosity产生原因：铸造材料凝固时会产生体积收缩，这种固体和液体之间的体积差异会在热节处形成空腔（缩松或缩孔）。MAINCAUSE:Duringthesolidificationofcastingmaterial,thevolumeofcastingwillshrink,whichformthecavityorshrinkageporosityunderthevolumedifferencebetweensolidityandliquid.改善措施：Solutions:1.在凝固时对半固态金属（在缩松产生的位置）增加压力。Increasethepressureofsemi-solidmetal,especiallytheareawheretheshrinkageporosityhappens.2.核查压力问题，如金属液静压力、检查增压设置等等。Inspectthestaticpressure,thepressureboostsettingetc.3.为缩松处提供额外的金属液。Provideextrametalmeltsinthetargetarea.4.料饼太薄或者尺寸变化太大。Toothinmaterialcakeoritssizevariesfrequently.5.检查产生缩松的部位与周围部位之间的温度差。Inspectthetemperaturedifferencebetweentheshrinkageareaandotherareas.6.降低压射时的金属液温度对改善缩松有帮助，但要注意是否会引起其他问题。Decreasethemetalmeltstemperatureduringpressureinjection.It’shelpfulforshrinkageporositysolution,butpayattentionwhetheritwillleadtootherproblems.7.检查合金成分。Inspectthealloycomponent.8.检查金属液温度波动（检查是否有剧烈的温度波动，金属液温度必须稳定）。Inspectthetemperaturefluctuationofmetalmelts.Checkupwhetherdrastictemperaturefluctuationexitsandthekeepsteadyofthemetalmeltstemperature.第七章缩陷Chapter7ShrinkPorosity--Porosityfromth