Laser welding uses high-energy laser pulses to heat materials in a small range. The energy of laser radiation diffuses into the material through heat transfer, which makes the material melt and form a specific molten pool. It is a new welding method, which is mainly used for the welding of thin-wall materials and precision parts. It can realize spot welding, butt welding, overlap welding, seal welding, etc., with high depth width ratio, small weld width, small heat affected zone, small deformation, fast welding speed, flat and beautiful weld, no treatment or simple treatment after welding, high weld quality, no air hole, accurate control, small focus light spot, high positioning accuracy, and easy to realize automation.