Effect of Nickel Aluminide on the Bainite Transformation

Abstract

It is known that the presence of precipitates in the austenite can influence its subsequent transformation kinetics. This investigation deals specifically with the role of nickel aluminide precipitates on the rate of the bainite reaction, in recent alloys intended for applications at about 400°C. It is demonstrated that the aluminides lead to an increase in the nucleation kinetics of the bainite. Furthermore, their presence increases the total quantity of bainite that forms, thus helping to reduce the amount of blocky retained-austenite in the final microstructure.