The generation of cracks is mainly due to the residual stress in the forming process, so releasing the residual stress or reducing the residual stress can reduce the generation of cracks. Generally speaking, the post-processing method is heat treatment for the formed parts. However, heat treatment can not reduce the cracks in the parts that have appeared before the heat treatment. Therefore, the most commonly used method to release residual stress is to use fiber laser and carbon dioxide laser in SLM equipment, among which fiber laser is used for forming and carbon dioxide laser is used for annealing, so as to release residual stress