Influence of hydrogen on magnetic properties of soft magnetic amorphous alloys
The influence of electrolytic hydrogenation on the magnetic properties of three different kinds of amorphous alloys has been investigated. The alloys studied were Fe/sub 83.3/Si/sub 3.5/B/sub 11.2/C/sub 2/, Fe/sub 38/Ni/sub 38/Mo/sub 2/Si/sub 8/B/sub 14/, and (Co/sub 86/Fe/sub 5/Cr/sub 9/)/sub 75/Si/sub 10/B/sub 15/. The experimental results showed that after hydrogenation the samples became very brittle and the soft magnetic properties degraded dramatically, but saturation magnetization sigma /sub s/ and average hyperfine field increased markedly. As hydrogen evolved from the charged samples which were placed in air at room temperature, the magnetic properties, toughness, and average hyperfine field were gradually recovered. >
Effect of hydrogen on the magnetoelastic behavior of amorphous transitional metal‐metalloid alloys
Internal friction and ΔE‐effect measurements have been made on Metglass 2826 and other ferromagnetic metallic glasses, electrolytically charged with hydrogen. Initially, the ΔE‐effect and magnetoelastic damping are strongly suppressed. The internal friction is dominated by a peak attributed to the stress‐induced reorientation of interstitial hydrogen atoms, with a mean activation energy of 0.5 eV. Various aging effects occur after charging. Recovery of charge‐induced bending is followed by a slower decline of the reorientation peak, a recovery of the ΔE‐effect, and an accompanying transient appearance of a magnetoelastic internal friction peak. The observed behavior indicates a strong interaction of hydrogen with domain walls, and leads to the prediction, confirmed experimentally, that hydrogen degrades the soft magnetic behavior of these alloys.
Pressure dependence of the Curie temperature in Fe-Zr amorphous alloys
Abstract The pressure dependence of the Curie temperature was investigated for Fe 1- x Zr x ( x = 0.07-0.40) amorphous alloys at pressures up to 14 kbar. The pressure shift of T c was found to be non-linear with pressure for all alloys except for the one with x = 0.2. The pressure derivative of T c for x T c by an expression, d T c /d p = - χT c + χ 2 T 2 c , proposed for inhomogeneous ferromagnetic alloys by Wagner and Wohlfarth. The results show that the Fe-Zr amorphous alloys are magnetically inhomogeneous. On the other hand, it was found that d T c /d p = λ 1 T c - λ 2 T 2 c holds for x 620.2.