Method for performing laser gradient cladding on alloy powder on surface of copper alloy

The invention relates to the copper alloy surface modification and in particular relates to a method for performing laser gradient cladding on alloy powder on surface of a copper alloy. The method comprises the following steps: by taking nickel-based alloy powder comprising the components of 4-6 percent of Al, 92-93.5 percent of Ni and the balance of impurities and the cobalt-based alloy powder comprising the components of 0.9-1.2 percent of C, 26.5-30.5 percent of Cr, 0.8-1.1 percent of Si, 3.4-5.4 percent of W, 1.0-2.0 percent of Fe, 1.2-2.0 percent of Ni and the balance of Co as a coating, mixing the powder, respectively blending the powder into paste by using an adhesive, pretreating the surface of a copper alloy needed to be treated, and respectively coating the obtain two pastes on a copper alloy matrix, so that the copper alloy matrix has a copper-matrix-nickel-based coating-cobalt-based coating-nickel-based coating-cobalt-based coating structure; and finally, performing laser cladding. The wear resist