Computer aided preforming tool shape design in hot forging

摘要

Shape optimisation methods can also be applied to the design of forming dies. They provide a very powerful tool that allows reducing the designing time, capitalising the expertise and standardising the technologies. In the frame of forging of axisymmetrical parts under hot conditions, the basic equations for the finite element simulation and for the optimisation problem are recalled. The utilised method is based on the direct differentiation of the discrete forging equations. A BFGS slgorithm makes it possible to find the solution in few iterations. The method is applied to several industrial problems, with some discussions on a relevant choice of the objective functions (that measures the quality of the design). New designs of preforming dies are suggested in this way, in order to avoid a piping defect and to increase the metallurgical properties of an aeronautical forged part.