Effect of Nanocrystalline Powders on the Structure and Properties of Dispersion-Hardened Alloy TiC - 40% KhN70Yu

This article examines aspects of the effect of nanocrystalline powders of ZrO^sub 2^, Al^sub 2^O^sub 3^, W, WC, WC-Co, NbC, and Si^sub 3^N^sub 4^ on the combustion, structure, and physical and physico-mechanical properties of new dispersion-hardened electrode alloy TiC - 40%KhN70Yu. This heat-resistant hard alloy, based on titanium carbide and a nickel alloy, was obtained by self-propagating high-temperature synthesis (SHS). It is shown that the addition of a nanocrystalline powder decreases combustion rate, with the magnitude of the reduction depending on the specific surface of the addition. It was determined that the structure of the synthesis products is modified appreciably by introducing a mixture of nanocrystalline powders into the initial charge. Here, additions of ZrO^sub 2^ and NbC have a positive effect on the main physico-mechanical characteristics of the alloy (strength, hardness, fracture toughness). Nano-powders of Al^sub 2^O^sub 3^ and Si^sub 3^N^sub 4^ have a negative effect on the alloy's physico-mechanical properties. The addition of WC-Co increases the flexural strength of the material, while the addition of W and WC increases its fracture toughness.[PUBLICATION ABSTRACT]