“…In the metal welding process, two or more pieces of metal welded together to form a welded joint which consists of base metal, weld metal, fusion zone and heat affected zone [15,21]. The welding process at the joint is a series of complicated processes such as local heating, metal melting and solidification, therefore, the welded joint is a region with heterogeneous ingredients, organization and mechanical properties [22,23]. The properties of the welding joint are affected by the process parameters of the laser welding such as frequency, beam power, focal length, defocus, spot size, welding beam speed, and shielding gas flow [24].…”