Hot sheet metal forming : The formulation of graded component characteristics based on strategic temperature management for tool-based and incremental forming operations

For some years press-hardening has been a fixed variable in the manufacture of high-strength structural components. Advantages to be derived from the press-hardening of components include, for example, high strength with low sheet thicknesses; this offers the potential for weight saving and has finally been successful in convincing automotive manufacturers. Bodywork concepts designed to take into account crash requirements, in addition to a general increase in strength characteristics, are also increasingly calling for zones of various characteristics to be embodied within the relevant structural components. In the present work essential aspects of heat treatment for implementation into the press hardening and roll forming processes are analysed and discussed. By adopting a specific temperature regime in the tool, characteristics zones can be set that demonstrate different tensile strengths and degrees of permanent elongation.