Magnetic properties of bulk Nd50Co10Fe 30Al10-xV x alloys

Abstract

This paper presents the results of study on the structure and the properties of the bulk Nd50Co10 Fe30Al 10-xVx (x = 0, 2, 4, 6, 8, 10) alloys prepared by arc-melting and suction casting with water cooling. The cast surfaces of the samples are partly crystalline and the amorphous volume fraction increases with distance into cast samples. With increasing V content, the crystallization volume fraction increases and for x = 10, the alloy is fully crystallized. In general, the melting temperature increases, but Ms and Hc decrease with V content. The Curie temperature increases clearly from 430 K (x = 0) to 512 K (x = 10). Thermomagnetic measurements of all samples done in low fields indicate the existence of the Hopkinson effect, which shows a coherent rotation magnetization and a strong reduction of the magnetic anisotropy in partly crystallized samples. The field-cooled (FC) and the zero-field-cooled (ZFC) curves measured in low fields reveal an obvious separation from each other at low temperatures, pointing to the existence of a cluster-glass state. The cluster-glass fraction decreases with increasing V content in the samples.