Transverse magnetization due to shearing stress on amorphous ferromagnetic materials

It is shown that a shearing stress σ applied to an amorphous ferromagnetic sample magnetized along a longitudinal direction x, gives rise to a transverse magnetization component My. A square sheet (25 × 25 mm²) of Metglas 2826 (Fe40Ni40P14B6) was clamped so as to apply a shear stress, while the material was magnetized by a field Hxparallel to the clamps. The Mxcomponent is almost unaffected by the stress, while a transverse component Myappears, which depends on Hxand σ. At constant stress Myincreases with Hxup to a maximum, which reaches about 15% of the saturation Msfor kg/mm². By minimizing the sum of magnetostatic and magnetoelastic energies, Mycan be calculated as a function of Hx, σ and λ, the magnetostrictive relative elongation, determined by conventional methods. A good fit is found between the Myvs. Hxexperimental and calculated curves, limited to the high field region. Alternatively, the Mymeasurements can be used to calculate λ as a function of Hx. Values of λ vs. Hxconsistent for most of the measured curves are found in this way, which agree with the 11.5 × 10^-6saturation value, but deviate from low fields data obtained with conventional magnetostriction measurements. This discrepancy is probably due to the different stress conditions under which λ\´s are calculated or directly measured, or to some distribution of magnetoelastic anisotropy due to frozen-in stresses.