Mechanical-technological properties of beam welded high and ultra high strength steels

New car body requirements specially on weight reduction forced car manufact urers to reconsider their design strategies. The ULSAB project (Ultra Light Steel Auto Body) showed that the body structure weight can be reduced by 2 5 % by using high strength steels and innovative manufacturing technologies . In this investigation different high and ultra high strength steels (HSLA -, dual phase, TRIP- and high strength IF-steels) are welded with different beam welding processes (laser beam welding without and with filler wire, n on-vac electron beam welding and MSG laser hybrid welding). The mechanical properties are tested with static, dynamic and cyclic testing methods. The investigations are focused on the effects of geometrical and metallurgical notches. The investigations showed that the use of high strength steels in combination with the adequate joining techniques offer increased feasibilit y of lightweight structures.