Compositional short-range order and kinetics of ordering in amorphous zero magnetostrictive CoNiFe-SiB alloy

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Abstract
Isotropic compositional short‐range order (CSRO) and the kinetics of ordering were studied in the amorphous zero magnetostrictive alloy of composition (Co0.525 Fe0.075 Ni0.4)73 (Si0.4 B0.6)27, which has a sufficiently low Curie temperature (TC) and high crystallization temperature. Resistivity and/or TC measurements after quenching from preannealing temperature show that the reversible equilibrium CSRO is formed at a temperature greater than TC and this CSRO can be separated from the nonreversible topological short‐range order (TSRO). The reasons why CSRO can be separated from TSRO in this alloy are considered. The kinetics of ordering of CSRO were determined by resistivity measurements in well‐annealed samples; the activation energy and the frequency factor for ordering of CSRO were determined to be 1.82 eV and 1.83×1013 sec−1, respectively. The kinetic data reveal the existence of a distribution of relaxation times of width β, where β was calculated to be 2.5 assuming a log‐normal distribution. The approximate theory of CSRO was given by the formulation of which CSRO representing the mean square of the concentration fluctuation contributes to resistivity.