Self-Propagating High-Temperature Synthesis of Ni₃AI

Abstract

Abstract–Combustion synthesis of the Ni,AI intcrmetallic was studied using the self-propagating hightemperature synthesis (SHS) mode. Since the reaction wave propagates rather quickly through the sample in SHS, a successful application of this process requires an understanding of the influence of processing variables on its dynamics, and on the phase composition and microstructure of the product. Thus, the effects of green density, ignition power, preheating temperature, and the particle sizes of aluminum and nickel were investigated. In addition, nickel particles with different morphology were used. It was found that higher green density, lower ignition power and higher preheating temperature lead to fully reacted product with a well-developed microstructure. The reactant particle sizes and their morphology also significantly influence the product properties. The obtained results arc helpful in understanding the mechanism of for mation of Ni₃Al.