Physical properties of nearly zero magnetostriction Co-rich glass-coated amorphous microwires

Magnetic and mechanical properties of Co-rich amorphous microwires of nominal compositions (Co_1–xMn_x)₇₅Si₁₀ B₁₅ (0.08 < x < 0.11) and Co_56.5Fe_6.5Ni₁₀B₁₆Si₁₁ with nearly zero magnetostriction constant have been studied. Drastic changes of the hysteresis loop with the decrease of x from rectangular to flat shape were observed at x < 0.1, while the Co_56.5Fe_6.5Ni₁₀B₁₆Si₁₁ microwire showed rectangular hysteresis loops. Compositions with x ≥ 0.1 have small but positive magnetostriction constant while negative λ_s values have been observed at x ≤ 4 0.09, indicating rectangular character of the hysteresis loop in samples with nearly zero and even for small negative λ_s. External stress dependence of switching field, H*, showed an increase of H*; with s for samples with x = 0.11 and a decrease of H* with σ for x = 0.1. Besides, microwires of the same composition but with different dimensions showed different H*(σ) dependencies.