High-Temperature Cermet Material Based on Intermetallic Nickel Matrix

摘要

A method for synthesis of an intermetallic nickel matrix reinforced with particles of different refractory compounds added at different concentrations is considered. Prepared materials are based on two variants of a Ni_3Al-Cr-W-Mo-Ti-Hf alloy: type VKNA- 1V alloy and type VKNA- 1V alloy with increased tungsten content (VKNA-lV(W)). The intermetallic matrix is reinforced with nanoparticles of the oxides Al_2O_3, Al_2O_3 • Y_2O_3, and Al_2O_3 • Y_2O_3 • HfO_2, with the content of reinforcing component at 2 and 5 vol %. Samples are compacted by spark plasma sintering. The microstructure of prepared cermet materials (CMs) is investigated using scanning electron microscopy. The impact viscosity and flexural strength are determined. We establish the effect that the content and composition of the reinforcing component has on the physicomechanical properties of the high-temperature CMs based on an intermetallic matrix dispersion-hardened with refractory metal particles. Our findings show that the optimal combination of flexural strength and impact viscosity at room temperature is achieved in the CM sample in which the intermetallic matrix is based on VKNA-1V(W) alloy and the reinforcing component is represented by ternary oxide Al_2O_3 • Y_2O_3 • HfO_2 added at a concentration of 2%.