Structure and properties of dispersion-strengthened-with-nanosized particles refractory hard material TiC—Ni-alloy

Abstract

Some particularities of the effect of nanocomponents such as ZrO₂,Al₂O₃, W, WC, WC—Co, NbC, Si₃N₄ on the combustion process, the structure, and mechanical properties of a novel electrode dispersion-strengthened alloy TiC—40% Ni have been studied. The refractory hard alloy based on titanium and a nickel alloy has been produced by the method of self-propagating high-temperature synthesis. It has been shown that introduction of a nanosized powder causes reduction of the combustion velocity depending on the specific surface area of the additive. It has been found that upon introduction of nanodispersed powders into the green mixture the product structure undergoes significant modification. The ZrO₂ and NbC additives produce a positive effect on the main mechanical characteristics of the alloy (its strength, hardness, and crack resistance). In contrast, these properties are negatively affected by the Al₂O₃ and Si₃N₄ nanopowders. Enhancement of the material bending strength and crack resistance can be achieved by respective addition of WC—Co and W, WC. © 2003 Elsevier Ltd. All rights reserved.

Key Words:

• Nanosized powders
• Self-propagating high-temperature synthesis
• Composite materials
• Structure
• Mechanical properties