Magnetostriction of ferromagnetic metallic glasses

Linear saturation magnetostrictions (295 K) of Fe_80t-xCo_xB₂₀, 0?x?80, and Fe_80?xNi_xB₂₀, 0?x?60 (at. %) glasses are reported. The saturation magnetostrictions of the Fe-Ni-base glasses vary as the sqaure of their respective saturation magnetizations. The behavior in the Fe-Co-base glasses is strikingly different. The compositional trends suggest a difference in origin of magnetostrictions between Fe-Ni-base and Co-containing glasses. When magnetostrictions for these glasses are compared with those for Fe-Co and Fe-Ni polycrystalline alloys, the most significant discrepancies appear in the Fe-rich compositions. This is probably related to the difference in short range order between the crystalline and non-crystalline Fe-rich alloys: α-Fe is 8-fold coordinated whereas all of the metallic glasses studied show ～ 12-fold metal coordination.