Magnetization (0-10 Oe) and magnetic relaxation measurements were carried out in the temperature range between 4.2 and 300 K for three picture-frame samples of Fe65Ni35 alloy whose edges were parallel to 〈100〉, 〈110〉 and 〈111〉, respectively. The typical temperature Tg and the magnetic field Hg which correspond to the anomalous temperature in the χ-T curve and inflection field in the σ-H curve, respectively are summarized and H-Tg and Hg-T diagrams are obtained. A strong magnetic relaxation is observed along the Hg-T line. The dependence of Hg on the crystallographic direction and on the temperature are discussed by the thermal activation process of the 180° domain wall which is pinned strongly by the antiferromagnetic clusters below Tg. The anomaly of magnetization of Fe65Ni35 alloy can be interpreted by the macroscopic picture of the coexistence of ferromagnetic and antiferromagnetic-like regions which may be caused by a statistical fluctuation of alloy composition.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics