Optimization of metal forming processes for improving final mechanical strength

Abstract

The fundamental mechanical assumptions and the basic principles of 3-dimensional FE discretization are briefly summarized. Several important numerical developments for efficient and accurate computation of large plastic deformation are discussed. Material behavior must be known precisely: material parameters of the constitutive law, thermal law and friction law must be determined by experimental tests and identification procedures by inverse modeling. Is it also necessary to avoid the possible onset of defects, such as crack opening, by introducing damage modeling in the cost function. A parameter sensitivity analysis is utilized in order to select the most important factors: shape of the preform, tools geometry, etc. The practical optimization is carried out by a genetic algorithm technique or by a surface response method. Moreover, for assessing the fatigue behavior, a more local approach is necessary in order to take into account material evolution at the micro scale.