深冷处理对火焰熔覆Ni35合金涂层组织和性能的影响

Effect of cryogenic treatment on microstructure and properties of flame clad Ni35 alloy coating

采用火焰熔覆技术在45钢基体上熔覆Ni35自熔性镍基合金涂层,对其进行不同时间的深冷处理,并进行力学性能测试和微观组织分析。结果表明：深冷处理有效改善了涂层的微观组织,进一步提高了涂层的力学性能。当深冷处理8 h时,涂层的力学性能最佳,涂层表面的硬度较未深冷处理涂层提高了2.01 HRD,摩擦磨损量减少54.22%。涂层中网状组织结构被细化,Cr7C3碳化物析出量增加及其碳化物组织均匀化是硬度和耐磨性提高的主要原因。

Ni35 self-fluxing Ni-based alloy coating was clad on the substrate of 45 steel by flame cladding technique and subjected to cryogenic treatment under different time.Then the mechanical properties and microstructure were analyzed.The results show that cryogenic treatment can effectively improve the microstructure of the coating and further improve the mechanical properties of the coating.When cryogenic treatment is applied for 8 h,the mechanical properties of the coating are the best,which the hardness is 2.01 HRD higher than that of the untreated coating and the friction wear lose is 54.22% lower than it.The main reasons for the increase of hardness and wear resistance of the coating are microstructure refined,Cr7C3 carbide precipitated and the carbide homogenization.