Experimental and numerical investigation of forming defects and stress analysis in laser-welded blanks during deep drawing process

In this study, welding and forming defects in a deep drawing process of laser-welded blanks (LWBs) are investigated both experimentally and numerically. LWB is used to achieve minimum distortion and desirable weld quality. However, some unfavorable residual stresses are added throughout the forming operations, which decrease the lifetime of LWBs. The objective of this study is to estimate the effect of five significant process parameters on forming defects during the welding and forming of LWBs. To this end, the hole-drilling method is utilized to determine experimentally the residual stresses in diverse zones of LWBs. Besides, the laser beam welding and forming processes are simulated by SIMUFACT(TM) package and ABAQUS(TM) software, respectively. The validation results show that the proposed model is very promising to estimate residual stresses for LWBs in industrial parts, especially in automobile industries. Studying the effect of varying process factors, it is noticed that the joining quality of the weld region is enhanced by applying the high-level spot size which has an optimum range to prevent the probability of brittle crack.