Effects of Si substitution on magnetic properties of ? with ? and Co

TLDR: The effect of substituting small amounts of Si for Fe and Co on the structure and magnetic properties of arc-melted ( and Co) compounds were studied by means of x-ray diffraction and magnetization measurements as discussed by the authors.

Abstract: The effect of substituting small amounts of Si for Fe and Co on the structure and magnetic properties of arc-melted ( and Co) compounds were studied by means of x-ray diffraction and magnetization measurements. X-ray diffraction study of indicates that the samples are single phase with the rhombohedral -type structure. The substitution of Si for Fe or Co leads to an approximately linear decrease in the unit cell volume. The saturation moment at 1.5 K decreases linearly with increasing Si concentration, being an approximately linear rate of about per substituted Si for and about for . The Curie temperature of is found to increase with increasing x from 476 K for x = 0 to 572 K for x = 3; however, of shows a monotonic decrease from 1213 to 651 K as x increases from 0 to 3. X-ray diffraction measurements of magnetically aligned powders show that the compounds with x = 0-3 have an easy-plane type of magnetic anisotropy. The easy magnetization direction of compounds changes from basal plane to c-axis with increasing Si concentration. The samples with x = 2 and 3 exhibit uniaxial anisotropy at room temperature.