Cornerradius(mm)Clearance(mm)FirstdrawingRp=,Rd=(.t)RedrawingRp=,Rd=(.t)EllipticaldrawingRp=,Rd=Longside:.,shortside:.TableTestconditionsinfirstdrawingTypeRp(mm)Rd(mm)A.B.C.D.H.Parketal./JournalofMaterialsProcessingTechnology()—..BlankshapeandmeasurementThefinalproductisofanellipticalshapethatconsistsofacirculararcatthelongsideandastraightlineattheshortside.Theblankshapedesignedbytrial-and-errorwardeepdrawingwillaffecttheformability.Researchworksforabetterunderstandingofsheetmetalformingprocesseshavebeencarriedoutusingdiversetechnologiesincludingexperimentationandthefiniteelementmethod(FEM).Theformabilityofnon-axisymmetricalshapeshasbeenexploredundertheprocessconditionsthattheblanksizeisdifferentbetweenthemajorandminoraxesandthatthematerialflowisnon-uniform[].Itisimportanttochangetheblankshape,becauseablankcomesintocontactwiththedie[,].Inthisstudy,thecornerradiiofthepunchanddiefortheellipticaldeepdrawingprocesswerestudiedtoinvestigatetheirinfluenceonformability..Experimentalwork..ExperimentalmaterialThematerialusedinthisstudyisanelectro-galvanizedsheetsteelSECEwithathicknessof.mm.Tensiletestswerecarriedoutinthedirectionsof,andtotherollingdirection.Thegaugelengthandwidthofthetensilespecimenswereandmm,respectively.Themechan-icalpropertiesinthetensiledirectionareindicatedinTable.D.H.Parketal./JournalofMaterialsProcessingTechnology()—TableMechanicalpropertyinthetensiledirectionDirectionYieldstrength(MPa)Tensilestrength(MPa)Elongation()..ExperimentalequipmentDeepdrawingtestswerecarriedoutusingapunchwithadiameterofmmandadiewithadiameterofmm.Fig.presentsthedimensionsofthetoolsusedinthefirstdrawingprocess.TheclearanceandthecornerradiiofthepunchanddiearelistedinTable.Theformingsequencefortheproductconsistsofthreeprocesseswhichare:(a)firstdrawing；(b)redrawing；(c)ellipticaldrawing.Thecornerradiiofthepunch(Rp)anddie(Rd)weredifferentforeachprocess.Theinitialblank-holderforcewasdeterminedastheminimumforcethatcouldpreventthewrinklingoftheblanksandwaskeptconstantduringthetestforeachblank.Ellipticaldeepdrawingtestswereperformedatvariouscornerradiiinatmechanicalpress.ThecornerradiiofthepunchanddieinfirstdrawingwerethethreetypesmentionedinTable.Fig..Dimensionsofthetools(mm)usedinthefirstdrawingprocess.TableCornerradiusandclearance（t=.mm）ProcessCornerradius(mm)Clearance(mm)FirstdrawingRp=,Rd=(.t)RedrawingRp=,Rd=(.t)EllipticaldrawingRp=,Rd=Longside:.,shortside:.TableTestconditionsinfirstdrawingTypeRp(mm)Rd(mm)A.B.C.D.H.Parketal./JournalofMaterialsProcessingTechnology()—..BlankshapeandmeasurementThefinalproductisofanellipticalshapethatconsistsofacirculararcatthelongsideandastraightlineattheshortside.Theblankshapedesignedbytrial-and-errorwa种这些基本模式综合变形。在设计钣金加工过程中确定过程变量影响是很重要。尤其,冲床和模具角半径将直接影响到拉深成形性。科研工作使更好理解板料成形过程已经进行了一定应用包括实验和不同技术有限元法(FEM)。非轴对称形状成形探讨了工艺条件下毛坯尺寸在主轴和次要轴条件下差异,以及物料流不均匀性[]。改变毛坯形状是很重要,因为毛坯最终影响到模具[、]。在这项研究中,对椭圆拉深过程冲床和模具角半径进行了研究，研究它们对成形性影响。相关作者-//$-前面内容科学B.V.出版社版权所有。PII:S-()-材料加工技术杂志()—.实验工作..实验资料材料应用于该研究是一种电镀薄钢板SECE薄钢板厚度为.毫米。拉伸试验进行了进一步研究，研究方向在度度和度方向。拉力长度和宽度标本分别为毫米和毫米。拉伸过程中力学性能显示于表。表力学性能拉伸方向方向屈服强度抗拉强度伸长（Mpa）（Mpa）（）表圆角半径及间隙（t=.mm）圆角半径（mm）间隙（mm）第一次拉伸Rp=，Rd=（.t）第二次拉伸Rp=，Rd=（.t）椭圆拉伸Rp=，Rd=长边：.，短边：.表第一次拉伸下测试类型Rp（mm）Rd（mm）A.B.C...实验设备拉深试验得出采用冲压机用个毫米直径和一个冲模直径为毫米。图给出了第一绘画过程中使用工装夹具大小。冲床和模具间隙以及圆角半径都列在表中。产品形成过程包括三个过程:(一)第一次拉伸；(b)二次拉伸；(三)椭圆形拉伸。冲压半径(Rp)及模具半径(Rd)在每个制造过程中都不同。确定了最初最小压边力能防止起皱和保持测试过程中每个坯料参数不变。椭圆形拉深试验圆弧半径在吨机械压力机下显得更复杂。冲压圆角半径和模具在第一次拉伸时三种类型在表中有所提到。..零件毛坯形状和测量最终产品椭圆形状是由长边圆弧和短一面一条直线所组成。所设计毛坯形状试误只是简单由等效曲面面积到最终产品尺寸组成，然而最终毛坯尺寸是通过大量实验证实[-]。图给出了所设计试误零件毛坯形状。图和给出了为每个椭圆深拉伸过程试验结果。产品壁厚分布测量已被用作点测量从微米产品中心到法兰边缘在间距毫米范围内,产品厚度从长、短两边来测量。图.尺寸工具(mm)用于第一拉伸过程图.所设计试误零件毛坯形状图.每个过程试验结果图.椭圆拉深产品.结果和讨论在计算材料时使用是电镀钢，它应力-应变关系特点为Mpa。（）在模拟过程中应用变量如下:()板料厚度，t=.毫米；()模具直径，毫米；()冲头直径，毫米；()压边力,N；()杨氏模量,.MPa；()泊松比,.；()库仑摩擦系数,.。薄板，冲头，模具和压边圈间磨擦系数由于使用了拉伸油后湿摩擦系数为.。假定摩擦系数在运行过程中会都保持不变。有限网系统由结点和元素组成。通过几何对称性,四分之一毛坯得到考虑。图显示了毫米变形网格配置。板料成形过程中可成形性和生产力,可以提高冲头和模具圆弧半径。为了展示了变形形状变化相应变形网格边界轮廓对冲床高度影响都显示在图。假使Rp=.毫米Rd=毫米,计算结果和实验结果最好吻合在毫米。图显示边界轮廓形状在Rp=.和Rd=条件下计算和试验结果之间比较。同时图显示了在Rp=.毫米和Rd=毫米条线下边界轮廓形状在计算和实验结果下比较。图.产品第一次拉深时厚度分布图.边界轮廓形状在计算和实验结果下比较。(A型)图.边界轮廓形状在计算和实验结果下比较。(B型)图.边界轮廓形状在计算和实验结果下比较。(C型)在Rp=.毫米和Rd=毫米条件下,沿拉深方向厚度分布和与横向方向一下子毫米显示在图。在凸肩附近长边厚度小于短边,这也是和实验结果相符。凸缘区域厚度分布实验结果和计算结果不同。图显示在Rp=.毫米和Rd=毫米下实验结果和有限元方法比较，同时图显示实验结果和有限元方法在Rp=.毫米和Rd=毫米条件下比较。在整个区域，壁厚分布在实验和计算结果下很相符。一种为金属薄片成形设计最优化工艺参数已经形成。拉深成形工艺优化设计条件下圆弧半径能得到更好品质产品。图.比较实验结果和有限元方法。方法（类型A）图.比较实验结果和有限元方法。方法(类型B)图.比较实验结果和有限元方法。方法(类型C).结论产品横截面,冲头圆弧半径(Rp)和模具圆弧半径(Rd)被认为是主要设计参数。这个研究集中在获得设计变量如冲头圆弧半径和椭圆形拉深模具产品。结果作如下综述：最优冲头圆弧半径和模具在成形过程中改善在椭圆形拉深过程中提出了。统计分析在椭圆形杯子拉深中已经应用。凸模圆弧半径和模具在计算结果与实验结果上吻合。rdeepdrawingwillafecttheformability.Researchworksforabetterunderstandingofsheetmetalformingprocesseshavebeencarriedoutusingdiversetechnologiesincludingexperimentationandthefiniteelementmethod(FEM).Theformabilityofnon-axisymmetricalshapeshasbeenexploredundertheprocessconditionsthattheblanksizeisdifferentbetweenthemajorandminoraxesandthatthematerialflowisnon-uniform[].Itisimportanttochangetheblanks附录引用外文文献及其译文AstudyontheimprovementofformabilityforellipticaldeepdrawingprocessesD.H.Parka,*,S.S.Kanga,S.B.ParkbAbstractThepunchanddiecornerradii,thelubricantcondition,theworkingspeed,theblank-holdingforce,thefrictionforceandtheclearancechangetheformabilityofthedeepdrawingprocess.Ingeneral,sheetmetalformingmayinvolvestretching,drawingorvariouscombinationsofthesebasicmodesofdeformation.Theinfluenceofthepunchanddiecornerradiiisofgreatimportanceinthedesignofsheetmetalworkingprocesses.Recently,mostoftheresearchforthesheetmetaldeepdrawingprocesshasbeenperformedontheformabilityofanaxisymmetricshape,buttherearenotanyconcretereportsontheformabilityofanon-axisymmetricshape.Inaddition,theconventionalcornerradiiofthepunchanddiehavebeendeterminedbytrial-and-errorusingindustrialexperienceandpost-processingtests,andonlyapproximatecornerradiiofthepunchanddiehavebeenpresented.Inordertoobtaintheoptimalproductsinthedeepdrawingprocess,ellipticaldeepdrawingtestswerecarriedoutwithseveralcornerradiiofthepunchanddie.Inthisstudy,theoptimalcornerradiiofthepunchanddieinthedeepdrawingprocesswithanon-axisymmetricblankshapeareproposed.Researchhasbeencarriedoutusingdiversetechnologiesincludingexperimentationandthefiniteelementmethod.CElsevierScienceB.V.AllrightsreservedKeywords:Non-axisymmetricdeepdrawing；Punchcornerradius；Diecornerradius；Finiteelementmethod；Blankshape.IntroductionManyresearchinvestigationsforcylindricalproductshavebeencarriedoutintothefundamentalsofthedeepdrawingprocess[—].Thus,thishasproducedmanyappliedshapessuchasrectangular,ellipticalandnon-axi-symmetrical.Ingeneral,mostoftheresearchforthedeepdrawingprocesshasbeenperformedontheformabilityofanaxisymmetricalshape,buttherearenoanyconcretereportsontheformabilityofanellipticalshape[—].Fortheimprovementoftheformabilityofdeepdrawingprocess,thepunchanddiecornerradii,thelubricantcondition,theworkingspeed,theblank-holdingforce,thefrictionforceandtheclearanceareinfluential.Ingeneral,sheetmetalformingmayinvolvestretching,drawingorvariouscombi-nationsofthesebasicmodesofdeformation.Itisimportanttodeterminetheinfluenceoftheprocessvariablesinthedesignofsheetmetalworkingprocesses.Especially,thepunchanddiecornerradiifordeepdrawingwillaffecttheformability.Researchworksforabetterunderstandingofsheetmetalformingprocesseshavebeencarriedoutusingdiversetechnologiesincludingexperimentationandthefiniteelementmethod(FEM).Theformabilityofnon-axisymmetricalshapeshasbeenexploredundertheprocessconditionsthattheblanksizeisdifferentbetweenthemajorandminoraxesandthatthematerialflowisnon-uniform[].Itisimportanttochangetheblankshape,becauseablankcomesintocontactwiththedie[,].Inthisstudy,thecornerradiiofthepunchanddiefortheellipticaldeepdrawingprocesswerestudiedtoinvestigatetheirinfluenceonformability..Experimentalwork..ExperimentalmaterialThematerialusedinthisstudyisanelectro-galvanizedsheetsteelSECEwithathicknessof.mm.Tensiletestswerecarriedoutinthedirectionsof,andtotherollingdirection.Thegaugelengthandwidthofthetensilespecimenswereandmm,respectively.Themechan-icalpropertiesinthetensiledirectionareindicatedinTable.D.H.Parketal./JournalofMaterialsProcessingTechnology()—TableMechanicalpropertyinthetensiledirectionDirectionYieldstrength(MPa)Tensilestrength(MPa)Elongation()..ExperimentalequipmentDeepdrawingtestswerecarriedoutusingapunchwithadiameterofmmandadiewithadiameterofmm.Fig.presentsthedimensionsofthetoolsusedinthefirstdrawingprocess.TheclearanceandthecornerradiiofthepunchanddiearelistedinTable.Theformingsequencefortheproductconsistsofthreeprocesseswhichare:(a)firstdrawing；(b)redrawing；(c)ellipticaldrawing.Thecornerradiiofthepunch(Rp)anddie(Rd)weredifferentforeachprocess.Theinitialblank-holderforcewasdeterminedastheminimumforcethatcouldpreventthewrinklingoftheblanksandwaskeptconstantdurin        附录引用的外文文献及其译文AstudyontheimprovementofformabilityforellipticaldeepdrawingprocessesD.H.Parka,*,S.S.Kanga,S.B.ParkbAbstractThepunchanddiecornerradii,thelubricantcondition,theworkingspeed,theblank-holdingforce,thefrictionforceandtheclearancechangetheformabilityofthedeepdrawingprocess.Ingeneral,sheetmetalformingmayinvolvestretching,drawingorvariouscombina

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