An inverse approach to the numerical design of the process sequence of tailored heat treated blanks

Abstract

While in industries lightweight construction gain an increasingly significant role and as weight reduction is often done with aluminum sheets, advanced production technologies have to be developed to be competitive for this evolution. Since steel sheet metal parts cannot be substituted directly with aluminum due to its minor formability, the usage of so called tailored heat treated blanks (THTB) is presented in this work. THTB are locally heat treated aluminum blanks from the 6,000-series alloy which exhibit a specific strength pattern optimized to the forming operation leading to a significantly improved formability for the manufacturing of complex aluminum car body parts. The enhancement of the formability is reached by a local heat treatment before the forming process. Due to the strong interdependency of heat treatment and forming operation, a numerical investigation of the process sequence is a prerequisite for a cost-effective usage of the THTB. An inverse approach on basis of a finite element simulation enables the determination of process parameters for an optimized THTB, thus having an effective and efficient engineering method for this technology.