Mössbauer studies of phase stability in mechanically stressed Fe–28at% Al alloy

Abstract Mechanical stress is introduced in Fe–28 at% Al alloy by filing a cast and homogenised ingot to fine powder. Long-range order is destroyed to a great extent as a result of this stress. Mossbauer and XRD studies show that heating the stressed alloy at 400°C is favourable to its reordering to DO 3 structure, while heat treatment in the range 480–540°C leads to the formation of α-Fe along with the other ordered phases. It is suggested that a fraction of iron ions is migrated from the A-sublattice to the B-sublattice due to vacancy creation and rearrangement during filing, and it remains there even after prolonged heating.