The influence of pre-heat treatment on laser welding of T-joints of workpieces made of selective laser melting steel and cold rolled stainless steel

The details produced by additive manufacturing have limitations in sizes, if you produce large details then there are large residual stresses. It is also economically advantageous to produce complexly configured details by additive manufacturing and then weld them to rolled or wrought cheaper details. The aim of this study is to investigate the influence of pre-heat treatment on laser beam weldability of Selective Laser Welding (SLM) stainless steel to Cold Rolled (CR) stainless steel. The results of metallographic studies and mechanical tests of produced welds are presented. The results showed that the pre-heat treatment of SLM workpieces affects the welded joint strength. The laser welding mode, keyhole or conduction, affected the microstructure and microhardness of the welds.