Mössbauer effect study of the as-quenched, annealed and crystallised Fe85−xCrxB15 metallic glass

Abstract 57 Fe Mossbauer effect study of the as-quenched, annealed and crystallized Fe 85− x Cr x B 15 metallic glasses with x = 1, 3, 5 and 8 has been performed. The fitting of the room-temperature Mossbauer spectra of the as-quenched alloys shows that the values of both the most probable and average magnetic hyperfine fields decrease rapidly at a rate of 23 kOe per at% Cr. The magnetic hyperfine field distributions exhibit bimodal structure for the 8 and 10 at% Cr compositions. The opposite trend observed in the variation of the Mossbauer hyperfine parameters with annealing temperatures for the Fe 80 W 5 B 15 and Fe 80 Cr 5 B 15 metallic glasses may be due to the effect of different magnetic behaviours of W and Cr. It also implies that the dense random packing structure in the two alloys is different. Mossbauer effect studies of the alloys crystallised at 1073 K for an hour reveal the growth of the precipitated α-Fe and σ-(Fe, Cr) crystalline phases with increase of Cr concentration.