1.The power and size of the laser focus are dynamically adjusted according to the processing requirements, and the processing process is monitored in real time. 2.The beam spot is small, and the processing accuracy is doubled. 3.The heat-affected zone is extremely small, the weld quality is high, and it is not easy to produce shrinkage, deformation, embrittlement and thermal cracking and other thermal side effects. The laser welding molten pool purification effect can purify the weld metal, and the mechanical properties of the weld are equal to or better than the mother material.