UFG to NC FePd by Combined Reaction Transformation Mode of Severely Plastically Deformed Disordered FePd

Abstract

AbstractNumerous studies have shown that equiaxed ultra fine grained FePd alloys can be produced by phase transformation of heavily deformed austenitic FePd via the combined reaction mode. As the magnetic properties can be improved by suppression of the polytwinned micro-constituent formed by the conventional ordering mode it appears reasonable to speculate that further grain refinement might lead to further enhancement. In order to reduce the grain size in bulk intermetallic alloys severely plastically deformed austenitic FePd has been phase transformed in this study. Equal channel angular pressing (ECAP) has been used to deform disordered FePd. The microstructure and property evolution during the deformation process and post-deformation annealing have been studied using SEM, TEM and hardness and magnetization curve measurements. The observations are compared to known results from use of other deformation processing routes, such as cold rolling.