WANG Wei, WANG Ping, GAO Liping, GUAN Haiyun, ZHANG Ningfei, HUANG Zhenyi
To enhance the performance of iron-rich nickel based alloy coatings, the plasma cladding (PTA) technique was employed to fabricate iron-rich nickel-based wear resistant alloy coatings, namely FeNi, FeNi/TiC, and FeNiWMo/TiC, on 45 steel substrates. The phase composition, microstructure, microhardness, and wear resistance of the coatings were systematically investigated. The results revealed that all three coatings exhibited excellent metallurgical bonding with the substrate. The primary phases identified in the coatings were γ-(Ni, Fe), M23C6, M7C3 and TiC. Notably, the incorporation of W and Mo did not alter the phase structure of the coatings. In the FeNi/TiC coating, TiC particles were predominantly large due to incomplete melting, with some primary TiC agglomerating at the grain boundaries of the γ-(Ni, Fe) phase. In contrast, the FeNiWMo/TiC coating displayed a significant refinement in TiC size, with a marked increase in fragmented TiC particles and a more uniform distribution of primary TiC. The W and Mo elements were found to be enriched around TiC, effectively inhibiting its growth and segregation. The average microhardness of the FeNi coating was measured at 588HV0.5, while the FeNi/TiC coating exhi-bited a substantial increase to 1 032HV0.5, demonstrating the significant hardening effect of TiC, but its wear resistance is reduced. In comparison, the FeNiWMo/TiC coating achieved a hardness of 1 085HV0.5 and exhibited a wear resistance 9.6 times higher than that of the FeNi coating, underscoring its superior performance in friction and wear applications.
