Magnetic properties of annealed FeNiZrCuB alloys

The aim of this work was to study the influence of the Ni content in Fe86-x NixZr7Cu1B6 (x = 5-86 at%) alloys on the magnetic properties after annealin g at various temperatures. The annealing temperatures were estimated from D SC measurements. It was found that the first crystallization peak T-x1 decr eases with increasing Ni content. The composition dependence of the coerciv ity and the magnetization at room temperature were investigated, too. After the heat treatment, the magnetization J(max)(x) decreases with increasing Ni content in contrary to the bell-shaped dependence of J(max)(x) in the as cast state. The concentration dependence (5-65 at % Ni) of the coercivity H-C(x) of annealed samples shows the same bell-type behaviour like those in the amorphous state. The coercivity of the annealed sample with 5 at% of N i is smaller than Hc(x) of the as-cast state. For higher concentrations of Ni the coercivity increases with annealing. The change of the coercivity wa s investigated for 25, 33, 43 at% of Ni at various annealing temperatures. In those cases, the coercivity increases with increasing annealing temperat ure up to temperatures corresponding to the first crystallization peak at w hich the coercivity reaches the maximum value. (C) 2000 Elsevier Science B. V. All rights reserved.