No abstract

No abstract

In the last decade, press hardening has become a fully established technology in both science and industry for the production of ultra-high-strength structural components, especially in the automotive industry. Beside the improvement of car performance such as safety and lightweight design, the production process is also one focus of trends in technology development in the field of press hardening. This paper presents an overview about alternative approaches for optimized process chains of press hardening, also including pre- and post-processing in addition to the actual forming and quenching process. Investigations on direct contact heating technology show new prospects regarding fast and flexible austenitization of blanks at compact device dimensions. By applying high speed impact cutting (HSIC) for trimming of press hardened parts, an alternative technology is available to substitute the slow and energy-intensive laser trimming in today’s press hardening lines. Combined with stroke-to-stroke control based on measuring of process-relevant parameters, a readjustment of the production line is possible in order to produce each part with individual, optimal process parameters to realize zero defect production of property-graded press hardened components with constant high part quality. Significant research in the field of press hardening was carried out at Fraunhofer Institute for Machine Tools and Forming Technology IWU, in the hot forming model process chain which enables the running of experiments under conditions similar to industrial scales. All practical tests were prepared by design of experiments and assisted by thermo-mechanical FE simulations.

Hot sheet metal forming is gaining in importance in many fields, because of its capability to produce more complex components than possible with cold forming. Hot forming is also used to influence the final material properties with the hot forming of manganese-boron steels being a good example. One of the major challenges in hot forming is the tribological conditions between the tool and sheet material at the required high temperatures. This article will discuss the influence of different tool material coatings, ranging from PVD to mechanically bonded ceramic coatings, on the tribological conditions during forming. It will also shed light on how these coatings influence the heat transfer between the component ́s material and the tool material.

No abstract