e[]usedacoolingsystemtocontroltheoveralltemperatureofthedie,inordertoobtainanoptimalheattransmissioncharacteristic,andreducetheoccurrenceofhardpointphenomenainthecastpiece,therebyimprovingthequalityofthepiece.Jongetal.[]developedamathematicalEq.fortheflowandsolidificationofmoltenmetalduringhigh-pressurediecasting,inordertoanalysethetemperatureconditionsandsolidificationstrainofdie-castcomponentsinfer,sothedesignerisunabletoevaluateandhandlethedeformationresultingfrommaterialandthermalexpansionandshrinkageofthedie.Theparametersofdifferentcoolingsystemscancauselargetemperaturegradients,anddifferentdeformations.AlthoughFEMsoftwareiscapableofanalysingthefillingflowandcoolingconditionsofpressure-injectedmetalandtheheatstress,heatstrainandtemperaturedistributionconditionsofadie-castingdieundervariouscoolingsystems,theestablishmentofananalyticmodelisverydifficult,especiallyforDfree-formgeometry.Besidesunderstandingtherequirementsofmulti-cavitydies,andthemetalflowandsolidificationprocess,thedesignershouldbefullyacquaintantedwiththebasicfiniteelementsoftware.Integrationcanbeachievedandcansavealotofmoneyandtimeonlyifacompleteunderstandingoftheprocessofdiemanufacturingisavailableandeliminatetheannoyancecausedbymovingofpersonnel.Initially,considerthedesignoftheventgateandoverflowgateintheprocessofinjectionandflowtofillthediecavityduringcoldroomdie-castingasinvestigatedbysimulationbyGarber[].Whenmetalcastingusingaplungerintoacavity,heconsideredthechangeoccurringinthemetal,andthereplacementoftheairinthecavitybymoltenmetal.Subsequently,Garber[,]showedthattoolargeortoosmallaplungerspeedwillaffectthecastquality.GroeneveltandKaiser[]studiedanddiscussedtheinfluenceofthespeedofinjectionofthemoltenmetalintothecavity,andflowdistanceandcavitytemperatureonthequalityofproductaftercasting.Accordingtotheexperiment,thedistanceofmoltenmetalflowincreaseslinearlyasthedie-castingspeedincreases,asdoesthedietemperature.Therangeoftemperatureisapproximately–C.Otherstudies[,]proposedtheimportanceofinitialtemperature(pre-heattemperature)ofthedie,andpointedoutthattoolowapre-heattemperaturewouldtendtocausefailureinfillingupthecavityinsidethediebythedie-castingliquid,andresultinformationfailure.Ahighertemperaturemayincreasethecoolingtimeandreduceproductivity.Truelove[]usedacoolingsystemtocontroltheoveralltemperatureofthedie,inordertoobtainanoptimalheattransmissioncharacteristic,andreducetheoccurrenceofhardpointphenomenainthecastpiece,therebyimprovingthequalityofthepiece.Jongetal.[]developedamathematicalEq.fortheflowandsolidificationofmoltenmetalduringhigh-pressurediecasting,inordertoanalysethetemperatureconditionsandsolidificationstrainofdie-castcomponentsin流经距离和腔内产品铸件上表面温度。根据压铸件不同浇注初始温度实验可得太低预先加热温度可能引起铸塑料液堵塞流道，从而发生故障。但较高温度可能增加冷却时间和减少生产能力。Truelove使用一个冷却系统控制压铸过程整个温度，目是获得一最佳传热特征，减少压铸件热节问题发生，从而改善铸件质量。Jong和一些人发明了一个用于熔融金属在高气压压铸期间流动和凝固数学方程，以便分析型腔内压铸元件温度情况和冷却应力。kenichiro和一些人使用有限元法分析和设计压铸模；结果不仅改善精度，但被考虑因素还有许多，如压模铸件压力、浇铸液体流动速度、粘性和材料随温度和相变化机械特性。使用CAD\CAE故障软件对压出板系统设计过程研究，目是减少压模设计过程中人为误差。它使用CAD软件创造一个形式自由模型、使用有限元软件分析压铸过程情况。它模拟压铸件和在不同参数（冷却线长度R、开槽中心距L、孔道直径D）下铸件变形温度分布，如图所示。它使用一个推断系统建立了关系图，冷却通道和自由形态压出板之间关系，变形和冷却系统参数模型之间关系。根据推断模拟方法，它能描绘输入和输出变量之间复杂和不确定关系。一旦推断系统构造出输入和输出压力铸造参数关系，一个合理带有性能指标优选法能探索出最佳铸造参数。在这里，一个模拟退火测深优化方法被采用。这个模拟退火算法是通过模拟退火过程来减少性能指标。它已经被成功地应用到压铸模具设计中等。这个基础理论可以被广泛地应用。.压铸流动理论在压铸过程中大约时间花费在冷却过程中。压模铸件变形是由于浇铸过程中不均匀温度分布引起，它影响铸件质量。冷却系统设计者不得不考虑整体循环和计算压铸过程中不同阶段变形。铸造过程分析包括三主要阶段：第一，浇铸过程必须保证浇铸充满型腔。主要压模铸件流动方程被分成五阶段。在填充阶段，模槽在高压下充满浇铸塑性流体。.建立冷却系统和压铸模具变形之间关系高气压注射铝合金压铸铸造压力大约是–Mpa；通常注射压力随时间而变。为了研究铸造过程压力影响，Dochler和Borton使用阴极射线示波器和照相机分析铸造过程中气压变化，那就是说高压充填、冷却和顶出。压铸模具设计包括流道、均匀型腔布置、分析压铸模具寿命（残余应力）、冷却系统等等。这个研究结果目是找到适合铸造任何工件压铸模具最佳冷却系统。假定铸造条件是：压铸压力Mpa、浇注速度.m/s、压铸循环时间s每次、预先加热温度oC、注射温度oC。对流入型腔液体基本假定：、三维流动；、牛顿流体；、层流；、不可压缩流体；、流体在垂直和水平方向无流速差别。根据在零件面闭合截面不同冷却参数，有个设计数据用于模拟压铸过程。根据三维流动模型模型流动分析，基本布局是一个自由形态表面。压铸模具表面温度被预先加热到一定温度(度)，熔融金属温度被控制在度。注射口温度特别需要维持在度。模具温度是度、冷却水温度是度、其它温度在填充时需要即时使用有限元分析控制，如图和所示。因为获得其临界温度条件需进行分析，变形分析使用三维流动和非线性条件对实体模型进行分析。各节点配置温度作为初始条件被输入。使注射口边界约束。条件充当三维热应变条件。机械性能随温度变化而变。它是从非线性稳定阶段分析中获得。上面讨论型腔流动分析结果用应变分析阶段执行显示在表格上。铸造过程中参数是很复杂和难以控制。在各参数和指标函数之间关系很难明确决定。用于实际压铸条件实验方法和统计法是不同。在实际运用中有很多地限制。研究使用一个神经网络去学习和培养一个系统，它用于压铸件变形和铸造过程中变形，使用这个神经网络完成各参数进一步地分析。图、温度梯度图变形分布同样地，输入参数关系建立（冷却系统参数：R,冷却线距离:D,孔道直径:L,开槽中心距）和在铸造过程期间输出参数（变形）被显示在附录上。建设一个完整推断系统，第一个必要条件是建立数据库。由输入和输出产生信息必须足够多。因而推断网络训练导流因素（冷却系统参数）应该完美和制造没有缺点产品。表格阐明了从三维模型流动分析获得压铸件冷却系统参数和极限变形。根据压铸模型发展，三层推断系统能自动地综合处理，它由冷却系统参数和铸件结果（变形）组成。不同控制参数被用于这个系统，它能够预先模拟压铸模型在不同控制参数下面变形。全部多项式方程被登记在附录（PSE=.X_）。表格比较这些出错预测模型和模拟情况。这模拟情况是从因为建立这个模型进行压铸模拟试验而设置个装置中得到这个数据集被用来检定这模型建立合理性。我们看得见来源于表故障大约，则可以得到建立这模型目。fer,sothedesignerisunabletoevaluateandhandlethedeformationresultingfrommaterialandthermalexpansionandshrinkageofthedie.Theparametersofdifferentcoolingsystemscancauselargetemperaturegradients,anddifferentdeformations.AlthoughFEMsoftwareiscapableofanalysingthefillingflowandcoolingconditionsofpressure-injectedmetalandtheheatstress,heatstrainandtemperaturedistributionconditionsofadie-castingdieunderva附录TheOptimalDesignofaCoolingSystemforaDie-CastingDieWithaFreeFormSurfaceAbstractThisstudyisonthefiniteelementandabductivenetworkmethodapplicationtodie-castingdieswithfree-formsurfaces.Thestudyaimstofindtheoptimalcoolingsystemparametersanddecreaseindeformationofadie-castingdie.Inordertoavoidthenumerousinfluencingfactors,thefree-formsurfaceofadie-castingdieiscreatedasanon-linearEq.ofapolynomialfunction.Theparametersofthecoolingsystem,includingthechannelspaceandchanneldiameter,areadjustedaccordingtothenon-linearEq..Anabductivenetworkhasbeenbuiltformodellingthediecastingcoolingparameters.Theabductivenetworkiscomposedofanumberoffunctionalnodes.Oncethecoolingsystemparametersaregiven,thisnetworkcanpredictthedeformationofthedie-castingaccurately.Asimulatedannealingoptimizationalgorithmwithaperformanceindexisthenappliedtotheneuralnetworkforsearchingfortheoptimalcoolingsystemparametersandtoobtainasatisfactoryresult.Keywords：Die-castingdie；Free-form；Neuralnetwork；Simulatedannealing.IntroductionThetypical,traditionaldie-castingprocessincludeshigh-pressurefilling,cooling,solidificationandejectionstages.Thecoolingstageisofgreatimportancebecauseitsignificantlyaffectsboththeproductivityandthequalityofthedie-castpart.Itiswellknownthataboutofthecycletimeofdie-castingisspentincoolingthehotmeltsufficientlysothatthecastpartcanbeejectedwithoutwarp.Thedesignofasuccessfuldiecanbeconsiderablyaffectedbyperfectfilling,whichreducesthecoolingtime,reduceswarpandinturnincreasesthequalityofthepart.Themainaimofthecoolingprocessistomaintainauniformtemperatureofthefillingandcoolingcycle.Accordingly,thereareatleasttwoimportantconceptsforthedesignerwhenconsideringthecoolingsystemandinestablishingcoolingprocessingconditions:()achievinguniformtemperatureand.()mini-misingthecycletime.Toachievethesetwoaims,thedesignermayneedanoptimalcomputer-aideddesignsystemtoachievearapidanduniformcoolingsystem.ThedesignofanoptimalsystemneedsanalysisofDheattransferduringthefillingandcoolingprocesses.Thethermalanalysistoolshouldpredictthetemperaturegradientanddeformationofthedie-body.Generallyspeaking,traditionaldiedesignstilldependsonexperience,duetothelackofanalyticabilityinmouldflowandheattransfer,sothedesignerisunabletoevaluateandhandlethedeformationresultingfrommaterialandthermalexpansionandshrinkageofthedie.Theparametersofdifferentcoolingsystemscancauselargetemperaturegradients,anddifferentdeformations.AlthoughFEMsoftwareiscapableofanalysingthefillingflowandcoolingconditionsofpressure-injectedmetalandtheheatstress,heatstrainandtemperaturedistributionconditionsofadie-castingdieundervariouscoolingsystems,theestablishmentofananalyticmodelisverydifficult,especiallyforDfree-formgeometry.Besidesunderstandingtherequirementsofmulti-cavitydies,andthemetalflowandsolidificationprocess,thedesignershouldbefullyacquaintantedwiththebasicfiniteelementsoftware.Integrationcanbeachievedandcansavealotofmoneyandtimeonlyifacompleteunderstandingoftheprocessofdiemanufacturingisavailableandeliminatetheannoyancecausedbymovingofpersonnel.Initially,considerthedesignoftheventgateandoverflowgateintheprocessofinjectionandflowtofillthediecavityduringcoldroomdie-castingasinvestigatedbysimulationbyGarber[].Whenmetalcastingusingaplungerintoacavity,heconsideredthechangeoccurringinthemetal,andthereplacementoftheairinthecavitybymoltenmetal.Subsequently,Garber[,]showedthattoolargeortoosmallaplungerspeedwillaffectthecastquality.GroeneveltandKaiser[]studiedanddiscussedtheinfluenceofthespeedofinjectionofthemoltenmetalintothecavity,andflowdistanceandcavitytemperatureonthequalityofproductaftercasting.Accordingtotheexperiment,thedistanceofmoltenmetalflowincreaseslinearlyasthedie-castingspeedincreases,asdoesthedietemperature.Therangeoftemperatureisapproximately–C.Otherstudies[,]proposedtheim        1附录TheOptimalDesignofaCoolingSystemforaDie-CastingDieWithaFreeFormSurfaceAbstractThisstudyisonthefiniteelementandabductivenetworkmethodapplicationtodie-castingdieswithfree-formsurfaces.Thestudyaimstofindtheoptimalcoolingsystemparametersanddecreaseindeformationofadie-castingdie.Inordertoavoidthenumerousinfluencingfactors,thefree-formsurfaceofadie-cast

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