The laser welding is a high-efficiency joining technique with high energy density

narrow heat affected zone and small workpiece deformation. However

problems still exist in laser welding

such as high cooling speed

cracks

pores

etc. Spatters and pores were effectively inhibited by adding suitable gas or using oscillating laser. The joint defect was reduced and the welding process stability was effectively improved by using arc assisted laser welding. Laser welding assisted by ultrasonic

magnetic and electric fields can improve joint performance by refining grain

reducing element segregation and crack sensitivity. The review on laser welding was summarized from three perspectives

namely process optimization

auxiliary heat source and auxiliary energy field. Finally

problems existing in the research of energy field assisted laser welding were analyzed and its development prospect was forecasted.