激光镍包纳米Al_2O_3增强复合涂层的摩擦磨损性能研究

Tribological Properties of Ni-clad Nano-Al_2O_3 Composite Coatings by High-energy Laser Irradiation

采用大功率CO2激光器在45#钢基体上制备激光熔覆镍包纳米A l2O3复合涂层,采用金相显微镜观察涂层表面形貌,在销-盘式摩擦磨损试验机上评价复合涂层与45#碳钢配副的摩擦磨损性能.结果表明:经激光熔覆处理制备的镍包纳米A l2O3复合涂层的耐磨性能显著提高,磨损质量损失降低38%,摩擦系数降低40%;复合涂层中纳米A l2O3的配比对其耐磨性影响显著,高配比涂层具有较好的耐磨性,而摩擦系数与A l2O3配比的关系不大.

Ni-clad nano-Al2O3 composite coatings were prepared on carbon steel plate by high power continuous wave CO2 laser beam. The fabrication of Ni-clad nano-Al2O3 composite coatings was investigated. The friction properties were examined under dry sliding condition using pin-on-disc tester. The results showed that the Ni-clad nano- Al2O3 composite coating had a microhardness value of 810Hv, greater than for without treated ones. The Ni-clad nano-Al2O3 composite coating possessed not only a higher wear resistance but also a lower friction coefficient. It is interest to note that the wear mass loss and friction coefficient of Ni-clad nano-Al2O3 composite coatings reduced to about 38% and 40% in comparison with those without coating respectively. The nano-Al2O3 were uniformly distributed in the carbon steel matrix and greatly increased the microhardness and tribological properties of the Ni-clad nano-Al2O3 composite coatings. The results also showed that the amount of Al2O3 significantly affected wear resistance of Ni-clad nano-Al2O3 composite coatings but they had little influence on their friction coefficient.