冲锻成形过程拉深增厚工艺的有限元分析VIP免费

第34卷第4期Vol134No14FORGING&STAMPINGTECHNOLOGY2009年8月Aug.2009冲锻成形过程拉深增厚工艺的有限元分析王新云,欧阳坤,夏巨谌,胡国安(华中科技大学模具技术国家重点实验室,湖北武汉430074)摘要:结合冷挤压与拉深工艺的特点,以双杯形工件为对象,提出了冲锻成形过程的轴向推力拉深增厚工艺,即在反向拉深的同时,对坯料侧壁施加轴向推力,进行强力拉深以达到拉深并增厚的目的。采用有限元模拟软件Dy2naform研究了拉深增厚工艺中材料的流动规律,分析了压环和压边圈的形状、压环运动速度、压边力、凸模与凸凹模之间的间隙对工件最小厚度和内壁最大厚度的影响。结果表明,压环能有效促进材料由外壁流向内壁圆筒,工件最小厚度和内壁最大厚度随压环速度增加单调递增,但均存在一个极值。关键词:冲锻成形;拉深增厚;双杯形件;数值模拟DOI:1013969/j1issn1100023940120091041017中图分类号:TG386文献标识码:A文章编号:100023940(2009)0420073206FEManalysisofdrawing2thickeningtechnologyinstamping2forginghybridprocessWANGXin2yun,OUYang2kun,XIAJu2chen,HUGuo2an(StateKeyLabofMaterialProcessingandDieandMouldTechnology,HuazhongUniversityofScienceandTechnology,Wuhan430074,China)Abstract:Combinedthecharacteristicsofcoldextrusionwithdrawingprocess,adrawing2thickeningtechnologywithaxial2forcewaspromptedfordouble2cup2shapedworkpieces.Anaxialthrustwasexertedtothesidewallduringback2warddrawingtoachievethepurposeofdrawingandthickening.TheFEMsoftwareDynaformwasutilizedtoresearchthematerialflowandtoanalyzetheimpactoftheshapeofpressureringandbinder,thevelocityofthepressurering,thebinderforceandtheeffectofgapbetweenpunchandpunch2dietotheminimumworkpiecethicknessandmaximumone.Theresultsshowthatthepressureringcanforcetheouterwallmetalstoflowtotheinteriorwall.Theminimumworkpiecethick2nessandmaximumoneincreasemonotonouslywiththepressureringvelocityincreasinguntiltheyreachthepeakvalue.Keywords:stamping2forginghybridforming;drawing2thickening;double2cup2shapedworkpiece;numericalsimulation对于大表面积且壁厚差变化较大的零件,通常的加工方法是:整体铸造、采用温/热锻后切削的加工方法、薄壁部与较厚部分通过焊接组合并热处理等的多工序方式来制造。这样不仅整体性能有所下降,成本及能耗也较高,而且工序多,导致效率较收稿日期:2008211220;修订日期:2009201220基金项目:国家自然科学基金资助项目(50705034)作者简介:王新云(1973-),男,博士,副教授电子信箱:wangxy_hust@2631net低,不符合节能与绿色制造的社会发展趋势。本文提出一种结合冲压与锻造技术特点的板料冲锻成形工艺,为成形这类具有大表面积且壁厚差较大的零件提供了一种新的塑性成形方法。主要特点为:以板材(或者管材)为坯料,通过冲压工艺成形出中空薄壁形状,并预先在拉深工序中储备足够体积的金属,再采用锻造工艺,对特定部位压缩增厚,以提高厚度与刚度。这样,不仅可避免仅采用冲压方法制造的零件没有足够厚度与刚度的缺点,也可避免仅采用锻造方法制造大表面薄壁零件时需[5]陆辛,费仁元,初红艳.复合冲压技术发展前景[J].锻压技术,2001,26(6)23225.[6]SethM,VohnoutVJ,DaehnGS.Formabilityofsteelsheetinhighvelocityimpact[J].JournalofMaterialsProceedingTechnology,2005,(168):3902400.[7]VohnoutVJ,DaehnGS.Reducingstampedpartdevelop2menttimewithpulsedenergyassistance[EB/OL].http:∥www1osu1edu/hyperplasticity,2004.[8]ShangJH.Electromagneticallyassistedsheetmetalstamping[D].Ohio:OhioStateUniversity,2006.[9]NeugebauerR,LoschmannF,PutzM,etal.Aproduction2orientedapproachinElectromagneticformingofmetalsheets[A].KleinerM.Proceedingsof2ndInternationalConferenceonHighSpeedForming[C].Dortmund,2006.[10]DehraMS.Highvelocityformabilityandfactorsaffectingit[D].Ohio:GraduateSchooloftheOhioStateUniversity,2006.要过高成形力的...