Reversible structural relaxation in Fe–B metallic glasses

Abstract

Relaxation effects in Fe–B metallic glasses have been studied through measurements of the Curie temperature (Tc) and changes of enthalpy. A monotonic increase inTcwith annealing temperature is observed for all compositions due to irreversible structural relaxation. This increase continues until the start of surface/bulk crystallization. The observed decrease inTc, upon further annealing is attributed to the strain introduced in the partially glassy system, which masks any evidence for reversible structural relaxation. Enthalpy measurements do show a small reversible structural relaxation. The magnitude of the effect is about a factor of 6 smaller than in ternary metalloid-containing glasses.