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在４５钢表面用激光束熔覆了ＴｉＮ_ｐ／镍基合金复合耐磨涂层，对涂层的组织和滑动磨损性能进行了分析，并讨论了不同激光工艺参数下涂层稀释度的变化情况。熔覆层由ＴｉＮ颗粒、γ－Ｎｉ初晶以及γ－Ｎｉ＋（Ｆｅ，Ｃｒ）_２３（ＣＢ）_６共晶构成。初晶γ－Ｎｉ中观察到高密度的位错，共晶化合物（Ｆｅ，Ｃｒ）_２３（ＣＢ）_６中出现了大量的层错亚结构，这些特征均使得涂层中的基体相得到了强化。在激光熔覆过程中硬质相ＴｉＮ颗粒边缘发生了部分溶解，冷却过程中重新凝固的ＴｉＮ以细小枝晶状独立形核析出。复合涂层中由于ＴｉＮ颗粒的存在使得涂层硬度显著提高，在摩擦系数不明显变大的前提下耐磨性提高了３倍。
TiN_p / Ni-based alloy wear-resistant coatings were cladded on the surface of 45 steel by laser beam. The microstructure and sliding wear properties of the coatings were analyzed. The changes of coating dilution under different laser parameters were discussed. The cladding consists of TiN particles, γ-Ni primary crystals and γ-Ni + (Fe, Cr) _23 (CB) _6 eutectic. High-density dislocations were observed in the primary crystal γ-Ni. A large number of layered sub-structures were observed in the eutectic compound (Fe, Cr) _23 (CB) _6, all of which enhanced the matrix phase in the coating . In the laser cladding process, the edge of hard phase TiN particles partially dissolved, and the re-solidified TiN precipitated in the form of fine dendrites during cooling. Due to the presence of TiN particles in the composite coating, the hardness of the coating is significantly increased, and the abrasion resistance is improved by 3 times under the condition that the friction coefficient is not significantly increased.