Effect of bending stresses on the high-frequency magnetic properties and their time stability in a cobalt-based amorphous alloy with an extremely low magnetostriction

摘要

An unusual effect of the stresses of bending (toroidal sample diameter D) on the hysteretic magnetic properties (H (c) , mu(5)) of an amorphous Co69Fe3.7Cr3.8Si12B11 alloy with an extremely low magnetostriction (|lambda (s) | a parts per thousand currency sign 10(-7)) is revealed. These properties are measured in a dynamic regime at a magnetic-field frequency f = 0.1-20 kHz. The coercive force of the alloy H (c) weakly depends on D at low frequencies (f < 1 kHz), and permeability mu(5) (H = 5 mOe), in contrast, is independent of D at high frequencies and is dependent on D at low frequencies. The samples subjected to high-temperature (390A degrees C) annealing followed by water quenching exhibit "anomalous" dependences: permeability mu(5) increases with decreasing toroidal sample radius, i.e., with increasing bending stresses. The detected dependences are related to the fact that magnetization reversal via the displacement of rigid domain walls is predominant at low frequencies and during static measurements and magnetization reversal via the displacement of flexible domain walls is predominant at high frequencies.