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A requirement for any material to be accepted by the automotive industry is that finite element (FE) simulations can be used to predict its behavior in both forming operations and crash conditions. So far, FE-simulations have been less accurate for austenitic stainless steel than for lower alloyed steels. The reason for this is the temperature sensitivity of the Transformation Induced Plasticity (TRIP) - effect in the low-alloyed austenitic grades of highest relevance for the automotive industry. Typically, temperature effects are not considered when sheet forming is simulated today. Therefore, new material models as well as a different simulation approach must be introduced for austenitic stainless steel compared to the materials used today. This paper describes the implementation of a new material model into LS-DYNA, which is capable of predicting the TRIP-effect in austenitic stainless steel in different forming operations with different temperature scenarios.

To increase crash performance in automotive vehicles it is necessary to use new techniques and materials. Components linked to crash safety should transmit or absorb energy. The energy absorbing capability of a specific component is a combination of geometry and material properties. For these components the chosen material should have high yield strength and relatively high elongation to fracture. These demands have led to increasing interest in the use of high strength stainless steels. The relative performance of three high strength carbon steels and two high strength stainless steel grades was evaluated through intrinsic and simulative tests. The rear bumper for a Volvo Car model in current production was manufactured using the five sheets tested to verify formability and behaviour under load. The bumpers were clamped in a rig that allowed quasi-static impact tests to be made.

Introduction of a new lubricant in the press shop involves various demands beside the pure tribological. Often, environmental concerns are considered most important. For the automotive industry specifically, compatibility with existing cleaning and painting systems as well as different joining techniques are key factors for acceptance of a new lubricant. The lubricants must of course also provide enough corrosion protection during storage. The present paper reports results from a screening of existing dry lubricants. Critical properties for further development are identified and some results from improved products are also included.