Effect of WC addition on TiC reinforced Fe matrix composites produced by laser deposition

The TiC/Fe ceramic metal composite (MMC) with WC particles addition was successfully produced by laser deposition process. The effect of the WC addition to the Fe-based MMC on microstructure and mechanical properties was investigated. The results indicated that the MMC deposit consisted of primary TiC, (Ti, W)C, M6C(Fe3W3C and Fe4W2C), austenite, and a little martensite besides initial TiC and WC particles. The MMC matrix was refined by the various M6C including blocks, faceted dendrites, coarse eutectics, eutectic groups, and nanoparticles. With the M6C strengthing, the hardness of the mixed matrix was 13% higher than that of the TiC/Fe composite. Moreover, a core-rim structure appeared on the primary TiC bonding with (Ti, W)C solid solution, as well as the initial TiC. The rim of the (Ti, W)C solid solution can not only improve the MMC toughness but also reduce the lattice misfit of the TiC/Fe interface, which was supposed to improve the interface strength.