Recent Advances in Laser Welding

Abstract

This paper describes a variety of fundamental research results of laser welding. The behavior and characteristics of a laser-induced plume were elucidated. In remote welding with a fiber laser, the effect of a tall plume (leading to shallow weld) was interpreted by considering the interaction of the incident laser beam against the zone of low refractive index. The laser absorption was higher in the cases of a smaller focused beam of fiber laser, lower welding speed and higher power, and the reason was interpreted by considering the size and location of a keyhole inlet and a beam spot. High power tandem laser beams could produce deep penetration, and laser welding in vacuum was developed for production of deeply penetrated welds. Laser direct joining was also developed for bonding of metal and plastic or CFRP.