激光熔敷Ni基合金涂层的腐蚀磨损性能研究

Study on Corrosive Wear Resistances of Laser Remelted Nickel-based Tungsten Carbide Alloy Coatings

系统研究了２１－４Ｎ阀门钢表面激光熔敷Ｎｉ基ＷＣ合金、Ｎｉ基Ｗ Ｃ稀土（ＣｅＯ２）合金涂层，在不同冲击速度和腐蚀介质浓度下的动腐蚀、动磨损和腐蚀磨损性能。试验结果表明，激光熔敷层的腐蚀磨损性能优于２Ｃｒｌ３钢Ｎｉ６０＋２０％ ＷＣ＋０．５％ ＣｅＯ２具有最佳的抗腐蚀磨损性能。根据试验结果，用多元回归分析方法分别建立了冲击速度、介质浓度与腐蚀磨损速率之间；动腐蚀速率、动磨损速率与腐蚀磨损速率间的定量关系并探讨了腐蚀磨损机理。

Nickel-based WC and nickel-based WC with various contents of rare-earth oxide(CeO2) were remelted on the surface of 21-4N valve alloy steel by a CO2 laser. The dynamic corrosion, dynamic wear and corrosive wear properties of the remelted coating under the condition of different impact velocities and vapious sulfuric acid concentrations were investigated systematically. The results showed that the laser remelted nickel-based WC alloy coatings presented higher corrosive wear resistance than that of 2Cr13 stainless steel. Furthermore, laser remelted Ni+20%WC+0.5% CeO2 coatings displayed the best corrosive wear resistance among all investigated remelted coatings. According to the experimental results, the quantitative formulas of corrosive wear rate with respect to impact velocities, acid concentration and between dynamic wear rate and corrosive wear rate were established by means of regressive methods. The corrosive wear mechanisms of these remelted coatings were also discussed.