In situ synthesised WC-reinforced Co-based alloy layer by vacuum cladding

Co-based alloy cladding layers (wallex50 and wallex55) were synthesised on 316L stainless steel by vacuum cladding. Experimental results showed that wallex50 composed of gamma-Co, WC, Co6W6C, Cr7C3, in which in situ reinforcement WC phases were homogeneously distributed in the layer, having a clear and stable interface structure. Wallex55 with externally added WC particles was composed of gamma-Co, WC, Co6W6C, Cr7C3, CrB, CoWB. The average microhardness of wallex50 and wallex55 was 794 +/- 29 and 939 +/- 24 HV, respectively. Nevertheless, wallex50 showed a better resistance to friction and wear than wallex55, which was not in a cross line with Archard's law. Relative wear resistance of wallex50 was 23.36, which was 1.56 times greater than that of wallex55. The improvement of friction and wear for wallex50 could be due to the fact that the in situ synthesised WC particles increased the friction and wear resistance by the pinning effect of the retained reinforced phase on the Co-based matrix.