Effects of laser beam defocusing on high-strain-rate tensile behavior of press-hardened Zn-coated 22MnB5 steel welds

Zn-based coatings have emerged as viable alternatives to the conventional Al-Si-coating for 22MnB5 press-hardening steel. However, excessive weld concavity associated with laser beam welding of Zn-coated 22MnB5 imposes an adverse effect on dynamic tensile behavior of the welds after press-hardening. In the present study, laser beam defocusing is used to mitigate excessive weld concavity during laser welding of Zn-coated 22MnB5 steel. The …