Forming-Limit Diagram of Interstitial-Free (IF) Steel Tailor-Welded Blank

Use of laser welded blanks of multiple sheets of material prior to forming is one of the current interests of automotive industries as it reduces manufacturing cost and weight and also improves the quality of the components. This research aims at predicting the forming limit strains of welded blanks using a strain rate-based necking criterion. Whereas interstitial-free (IF) steel has favorable forming property and automotive maker try to use it in automotive body, some investigation on forming limit of IF steel Tailor Welded Blank (TWB) has been done in this study. The forming limit diagram (FLD) of welded blanks is predicted by simulating the limit dome height (LDH) test using ABAQUS software. The TWB FLDs predicted by software are compared with the experimental FLDs obtained by LDH test. Failure location data of TWBs from experiments and prediction are also compared.