Method for evaluating the behavior of laser welded dissimilar material seams in single overlap configuration under impact loads by the example of twinning induced plasticity steels

Abstract

Due to increasingly more stringent environmental and safety regulations as well as the globally increasing but locally different customer demands, automanufacturers are in search of measures to meet these requirements. In order to do so, research and development departments particularly focus on sustainable, light weight solutions. Based on material and load adapted design, an economic way of using new materials must be realized. This integral method of construction results in a diversified use of materials in automobiles. Consequently, dissimilar material combinations are increasing in number and importance, including crash-relevant structural parts. Concerning joining technology, light weight design is a challenge, because the ability to join dissimilar material combinations is often accompanied by small tolerance windows for the production process. In other words, minimum variation of process parameters may lead to a significant quality change of the properties of the seam. The present study deals with an experiment which aims at evaluating the influence of process parameters on the mechanical properties of overlap joints under impact loads. Its setup is based on the Charpy impact test and evaluated by means of laser beam welded overlap specimens of austenitic high manganese twinning induced plasticity steels and ferrite low carbon steels.