Compositional Dependence of Physical Properties and Reversible Structural Relaxation Behavior in Fe–B–Si Amorphous Alloys

Abstract

Reversible structural relaxation behavior in Fe–B–Si amorphous alloys was discussed in terms of the structural model proposed by Dubois and Le Caer. According to the model, the structure of Fe–B–Si alloys (B<20 at%) consists of two regions. One is the region occupied by iron atoms without boron neighbours (region 1), and the other with boron neighbours (region 2). The silicon atoms occupy the region 1 preferentially. The validity of the model was confirmed for Fe_88−xB₁₂Si_x alloys (2≤x≤13) through the measurements of differential scanning calorie, Mössbauer effect and Vickers micro hardness. The reversible change in the electrical resistivity and in the enthalpy associated with structural relaxation were observed in Fe₇₈B₇Si₁₅ and Fe₇₅B₁₀Si₁₅ alloys. There is a significant difference between these alloys in the magnitude of the reversible changes. This difference can be explained well by the reversible structural relaxation within the region 1.