Abstract: Ni35, Ni45, Ni60 and Ni62 nickel-based alloy powders were coated on 45 steel and 316L stainless steel,respectively. The elements in the crack area of nickel-based alloy coating were detected by EDS, and the formation mechanism of the nickel-based alloy coating cracks was explored. In combination with the penetration flaw detection results of the cladding layer, the influence of the matching of nickel-based alloy material and the base material on the coating cracks was studied from the material composition and thermal physical properties. In addition, the wear resistance and hardness of the cladding layer and the substrate were tested using M-2000 type abrasion tester and HXD-1000 type microhardness tester. The results show that B, C, Si and other elements have segregated seriously in the crack area of the nickel-based alloy coating.The main reason for the crack formation of cladding layer is the joint action of internal stress, hard brittle phase and a large amount of segregation of inclusions in the final solidification stage of the coating. The composition of the nickel-based alloy coating and the difference of thermophysical properties between the coating and the substrate have great influence on the cracking sensitivity of the coating.The increase of the content of hard phase elements and the increase of the difference between the coating and the substrate improve the cracking tendency of the coating. Therefore, on the premise of meeting the surface modification requirements of the substrate, the coating cracking sensitivity can be effectively reduced by selecting the cladding materials with relatively small content of hard brittle phase and similar to the substrate thermal physical reason. In addition, the four kinds of nickel-based alloy coatings are superior to the substrate（45 steel and 316 L stainless steel） in terms of wear resistance and hardness, and have excellent help in enhancing the surface wear resistance and hardness of the substrate.