Combustion Synthesis of TiN with Liquid Nitrogen

Abstract

TiN combustion synthesis is investigated through a self-propagating reaction of titanium powder compacts of various packing density (40%, to 60% theoretical one) in liquid nitrogen under atmospheric pressure. By changing the position of ignition point, it is confirmed that the upward combustion propagation is more effective for getting higher conversion ratio than the downward one. It is considered that both the heat and evolved nitrogen gas propagate upward in the case of upward reaction propagation, resulting in higher TiN conversion ratio compared to the downward one. As a result of combustion synthesis of Ti compacts added with TiN powders, almost 90% of the TiN content can be attained with the addition of 45mol%, which is the composition to generate the heat of reaction close to the solid-side limits at the melting point of TiN.