Development of Materials Based on the NiAlCrMoCo System Reinforced with ZrO2 Nanoparticles

Abstract

This paper describes thermodynamic modeling of the NiAl–CrMoCo system with the calculation of the equilibrium composition and thermodynamic parameters of the system. NiAl-Cr-Mo-Co alloy samples of equiatomic composition, including those with a small addition of zirconium oxide nanoparticles, were obtained by spark plasma sintering of mechanically alloyed powders. It was found that the material had a two-phase structure with wedge-shaped regions enriched in cobalt and molybdenum with a gradient distribution. In addition, in the regions enriched with (Cr, Mo) phase, a lamellar σ phase was found. Fractographic analysis showed a positive effect of the fine-grained wedge-shaped regions on the damping of crack propagation. The alloy with the addition of zirconium oxide nanoparticles had a bending strength and an elastic modulus of 611 MPa and 295 GPa at 25 °C, and 604 MPa and 260 GPa at 750 °C, respectively, when tested in vacuum.