真空环境对激光熔覆镍基碳化钨涂层组织和性能的影响

Effect of Vacuum on Microstructure and Properties of Laser Cladding Ni-Based WC Coating

研究真空环境对激光熔覆镍基碳化钨涂层组织、性能的影响。结果表明:在真空试验条件下,涂层的组织得到改善,涂层中的粗大树状晶减少,组织更均匀、致密;涂层中的微裂纹显著减少,涂层中几乎没有气孔缺陷;涂层中的金属间化合物可以更均匀地弥散在镍基固溶体中,显著提高了涂层的硬度;涂层的摩擦磨损性能得到明显改善,涂层的摩擦因数相对于非真空试验条件下的摩擦因数降低了约14%,耐磨性提高了约56%;真空试验条件有效提高了涂层的综合性能。

The effect of vacuum test condition on the microstructure and properties of the laser cladding Ni-based WC coating is investigated.The results denote that under vacuum test condition,the microstructure of the coating is improved,the coarse dendrites in the coating are reduced,and the structure becomes denser and more uniform.The microcracks in the coating are significantly reduced,and there are almost no porosity defects.The intermetallic compounds in the coating are uniformly dispersed in the Ni-based solid solution,which significantly increases the hardness of the coating.In addition,the friction and wear properties of the coating are significantly improved.The friction coefficient is reduced by approximately 14% when compared with that in the non-vacuum condition,whereas the wear resistance is increased by approximately 56%.Under vacuum test condition,the overall performance of the coating is significantly improved.