Theoretical prediction of failure in forming of friction stir welded blanks

In this paper, the Marciniak-Kuczynski method is used to predict the forming limits of friction stir welded tailor-made blanks. Three different FEM models, having three different levels of the welds details implemented, are built and the straining limits of a prototype friction stir welded blank during the Limiting Dome Height (LDH) test is predicted by using the models. The imperfection parameter is determined such that the predicted failure limits in a simulated tensile test match the experimentally obtained ones. It has been shown that the implementation of the weld details is necessary for accurate prediction of the failure limits.