机械专业模具毕业论文翻译.pdf

Blankdesignandformabilitypredictionof complicatedprogressivediestampingpartusinga multi-stepunfoldingmethod ZhangZhibing,LiuYuqi,DuTing,LiZhigang StateKeyLabofMaterialProcessingandDieMould Technology,HuazhongUniversityof ScienceTechnology, Wunan,Hubei430074,China Abstract A multi-step unfolding method (MSUM) is developed for blank design and formabilityprediction ofcomplicatedprogressive diestampingpart .Inthemethod ,a finiteelementmodeloftheinverseapproach(IA)isdevelopedatalocalareaaccording tothestampingprocess,andtheintermediateshapeisunfoldedonareferencesurface atthelocalarea .Notonlytheinfluenceoftheconnection,blank-holderforceandthe friction ,but also the influence of the offsetting of the strain neutral layer with different radius of curvature at local area, are considered in the model ,which improves the calculation precision of the blank shape at each step .The key intermediateblank shapesandinitialblank shapecanbe generatedusingthe method with many times in an inverse sequence .The optimum blank shape also can be designedaccordingtotheformabilityoftheformingpart .TheMSUMisillustratedto theblankdesignofaprogressivediestampingpart ,andabenchmarktestiscompared withexperimentalandothernumericalresults. Keywords: Blank design Progressive die Multi-step unfolding method Inverseapproach 1.Introduction A large number of parts on automobile body are deformed by stamping ,and sometimes the features of the stamping parts are very complicated .In order to improve the quality and the efficiency of products ,many parts are formed using progressive die process .Comparing with simple press tool, progressive die has the advantagesofhigh qualityandefficiencyofproduct ,whichisespecially suitablefor large-lot production in a short delivery time .However ,it is very difficult to design strip layout in progressive die design ,and only the rich e