A Study on Laser Welding Application of the Cowl Cross Member for Ultra-High Strength Steel

Abstract

Article history:A cowl cross is a part of the car's instrument panel used to maintain the rigidity of the vehicle body side. The application of laser welding has the benefits of speed and thermal deformation compared to arc welding. An ultra-high strength steel sheet is used to reduce the weight of the vehicle body parts. Generally, formability of such a steel sheet is poor because its elongation is very low. For this reason, a method for cold forming of an ultra-high strength steel sheet is required. This paper describes how to improve the formability and weldability of the ultrahigh strength steel sheet. Mechanical tests of this material were also performed to evaluate the welding properties of CO 2 (GMAW) and those of laser welding.