Incremental Forming with Local Heating by Laser Irradiation for Magnesium Alloy Sheet

Abstract An incremental sheet forming system with dynamic local heating by laser irradiation was developed to form magnesium alloy sheet which is typical lightweight hard-to-form sheet metal. In this process, tool contact area of a blank sheet is locally heated by a moving laser beam spot to increase the material ductility and decrease the material strength dynamically and partially. Incremental forming experiments of AZ31 magnesium alloy sheet was carried out under several laser irradiation conditions and forming speeds using the developed forming system. The experimental results show that the formability of AZ31 sheets increased remarkably with increasing laser power. Defocusing distance of laser beam and forming speed also affected the formability. The results also indicate that residual stress of the formed product was markedly reduced to almost zero by local heating.