Microstructure and properties of in-situ synthesized Ni3Ta-TaC reinforced Ni-based coatings by laser cladding

Abstract The Ni3Ta-TaC reinforced Ni-based coating is synthesized in-situ on the substrate of the shield tunneling machine cutter ring by laser cladding to improve its wear resistance. The microstructure and strengthening mechanism of Ni-Ta and Ni-Ta-C coatings were studied respectively. The wear resistance of the two coatings was studied and compared with the substrate. The Ni-Ta coating is mainly composed of γ-Ni, Ni3Ta and Ta phases, while the Ni-Ta-C coating is mainly composed of γ-Ni, Ni3Ta and TaC phases. The wear resistance of Ni-Ta coating and Ni-Ta-C coating is 2 times and 4 times higher than that of 5Cr5MoSiV1 steel, respectively. It is expected to improve the wear resistance of the shield cutter ring.