The work presented the investigations results of the heat treatment effect in air at temperatures in 200–250°C on the magnetic characteristics and their homogeneity in ribbon samples of amorphous soft magnetic alloy based on cobalt AMAG-172 (Co–Ni–Fe–Cr–Mn–Si–B). The non-uniformity of the magnetic characteristics in the as-quenched state is associated with the manufacturing technology: the presence of gradients in the cooling rate of the ribbon. It is shown that heat treatment on air in the studied range of temperatures and durations of isothermal holding does not improve the magnetic characteristics in the ribbon and increase their homogeneity. The formation of bimodal and trimodal field dependences in magnetic permeability indicates delamination by ribbon thickness during annealing. A decrease in the maximum magnetic permeability is due to the reorientation of the magnetization perpendicular to the ribbon plane and across the ribbon axis in its plane. The obtained results are explained by the influence of anisotropic stresses induced as a result of oxidation and hydrogenation of the ribbon surface and its surface crystallization.
Nekrasov et al. (2025) studied this question.