Recently, the Xi'an Institute of Optics and Fine Mechanics transient chamber invented a cladding layer for the impact of strengthening methods to increase the mechanical properties of metal parts, especially high temperature fatigue mechanical properties. The technology has recently been authorized by the national invention patents. According to the different characteristics of cladding layer, this technology adopts reasonable impact process to eliminate internal defects of cladding layer, refine grain and increase residual compressive stress in cladding layer, finally increasing the mechanical properties of metal parts, especially high temperature fatigue Mechanical properties. Compared with the conventional technology, the invention can impact the formed cladding layer in stages during the metal 3D printing forming process, thereby eliminating defects such as cavities, looseness and micro-cracks in the cladding layer during the metal 3D printing, Of the density, enhance the density to enhance the mechanical properties, while ensuring the accuracy of metal 3D printing surface.