以钴为主体的涂层原材料粉末中添加Ni, Cr, Fe, C, Si, W, MgO, Y2O3和纳米Al粉等形成新型合金粉末体系, 在结晶器用Cu-Cr合金表面利用脉冲激光原位制备颗粒增强Co基合金涂层。应用金相显微镜、扫描和透射电镜等分析技术, 对实验制备样品涂层的组织结构进行研究。结果表明, 在优化了粉末成分及激光扫描工艺参数(50 W, 15 Hz, 3 ms, 4.0 mm/s)条件下, 制备出了与Cu合金基体界面冶金结合的钴基合金涂层; 在涂层内部以Co-Cr-W-C为主体元素形成了细晶、高硬度的合金组织, 涂层中原位生成了细小的陶瓷颗粒相, 起到了复合强化作用, 而W, Cr等强碳化物在基体中析出, 起到了弥散强化的作用。涂层中过渡层富Co区的出现导致了富Cu区的产生。

The newly developed Co-based alloy containing a certain amount of Ni, Cr, Fe, C, Si, MgO, Y2O3 and nano-Al powders is taken to prepare a ceramic particles, to reinforc Co-based alloy coating on surface of Cu-Cr alloy for crystallizer through pulse laser induced reaction in-situ. The microstructure morphology and coating mechanism is studied experimentally by means of optical micrograph, SEM, and TEM analysis techniques. The results show that under conditions of optimized powder elements and process parameters of the laser-scan (power 50 W, frequency 15 Hz, pulse width 3 ms, scan rate 4.0 mm/s), the coating with a metallurgical interface forms between the Cu alloy substrate and coating is prepared on the surface of Cu-Cr alloy.The structure of Co-Cr-W-C alloy with fine grain and high hardness is formed in the coating, and the ceramic particles in the coating are produced by YAG pulse laser inducing in-situ synthesis, which strengthen the coating. Carbides of W,Cr are precipitated in the coating and that dispersion strengthens the coating. The Co rich area formed in the transition layer of coating leads to the formation of the Cu rich area.