Influence of alloying the TiC0.5N0.5 carbonitride with zirconium on an interaction mechanism with the Ni–Mo melt

Abstract

The influence of alloying the TiC_0.5N_0.5 titanium carbonitride with zirconium on the mechanism and kinetic features of the contact interaction with the Ni–25%Mo melt (t = 1450°C, rarefaction 5 × 10^–2 Pa) is investigated for the first time by electron probe microanalysis and scanning electron microscopy. The main effects of the modifying influence of zirconium on the dissolution, phase formation, and structure formation processes which occur during the interaction of the Ti_1–nZr_nC_0.5N_0.5 carbonitride (n = 0.05 and 0.20) with the Ni–Mo melt are revealed and the factors promoting their manifestation are analyzed. The practical absence of zirconium and nitrogen in the composition of the K-phase (the Ti_{1 – n}Mo_nC_x metastable solid solution, where n ≤ 0.65 and x = 0.7 ± 0.1) is confirmed experimentally. It is shown that the zirconiumenriched Ti_0.80Zr_0.20C_0.5N_0.5 carbonitride cannot be recommended as a refractory component of cermet because of the limitations of the chemical character.