Effects of nano-TiC substitution on the magnetic properties of Ti(C,N)-based cermets

Abstract

In this study, the impact of partial substitution of micro-TiC by nano-TiC on the microstructure, magnetic characteristics and mechanical behaviors of TiC–10TiN–6WC–30Ni–4 C (mol%) cermets was investigated. The results revealed that these cermets consisted of mostly ceramic phases and some Ni-based binder phases, regardless of the substitution level. The average size of ceramic grains altered slightly with increasing nano-TiC substitution, which firstly decreased a little and then increased. The partial substitution of micro-TiC by nano-TiC caused a significant reduction of the magnetization in cermets with increasing the lattice parameter of the binder phase. The saturation magnetization and remnant magnetization reduced with the increase of nano-TiC substitution. The cermets underwent a ferromagnetic to paramagnetic transition at room temperature, as the nano-TiC substitution increased. The magnetization variation is related to the increased solid solution of Ti and W in the binder phase by nano-TiC substitution. Cermet with 7.5 mol% nano-TiC substitution demonstrated the best comprehensive properties, with the Curie temperature of 210 K, bending strength of 1665 MPa and hardness of 87.1 HRA, respectively.