Magnetic properties of the Laves-phase compounds Fe1-xCoxBe2

The magnetic properties of polycrystalline and single-crystalline Fe1-xCoxB e2 were investigated by magnetization, Mossbauer, and torque measurements. Curie temperature (880 K at x = 0) and magnetic moment (1.94 mu(B) at 5 K f or a specimen with x = 0) decrease with increasing content of Co. The Go-co ntent dependence of the magnetic moment could be explained by considering m agnetic moments of Co. Co seems to have a magnetic moment induced by an int eraction between Co and the nearest neighbor iron atoms. Hexagonal anisotro py constants were determined as K-u1 = 9.7 X 10(5) erg/cm(3) and K-u2 = 9.9 X 10(4) erg/cm(3) for a specimen with x = 0 and K-u1 = 3.4 X 10(5) erg/cm( 3) and K-u2 = 3.3 X 10(4) erg/cm(3) for x = 0.1. Co substitution is ineffec tive to the improvement of the magnetic anisotropy of FeBe2. (C) 2000 Elsev ier Science S.A. All rights reserved.