一种锻件预成形设计的新方法

A New Method for Preforming Design of Complexly Shaped Forging

一种锻件预成形设计的新方法刘庆斌，季忠，刘马宝，吴诗春为了在锻造过程中合理地分配金属，使金属在终段时完全充满模腔，不会出现缺陷，往往在终锻前进行一次或多次预锻，即预成形（Ｐｒｅｆｏｒｍｉｎｇ），而要进行合理的预成形设计，掌握金属流动规律是关键。从目前...

Preforming design of complexly shaped forging by FEM(Finite Element Method) backward simulation technique is almost impossible due to work hardening and difficulty in treatment of dynamic boundaries.UBET(Upper Bound Element Technique)backward simulation technique can achieve such preforming design but at the sacrifice of precision due to the assumption of straight edges.It seems natural that we propose a new method for preforming design that combines adroitly the advantages of both FEM and UBET simulations.What we propose is:crude prefoming design with UBET backward simulation and then repeated revisions with FEM forward simulation until satisfactory precision is obtained.Fig. 1 shows a complexly shaped H forging to be made.By the method just described,we find that the billet should be as shown in Fig.2a.This billet can fill up completely the space of die as shown in Fig.2b.Thus our method can succeed in making a complexly shaped H forging with good precision.