FeCoBSiNB bulk metallic glasses with cu additions

Abstract

The effect of Cu additions (1, 2 and 3 at.%) on the glass forming ability (GFA) and magnetic properties of [(Fe0.5Co0.5)0.75Si0.05B0.20]96Nb4 is studied. As the Cu content increases, the GFA deteriorates. The structure of the samples, as well as the crystallization behavior was insitu studied by means of synchrotron beam. The as-cast 1 mm diameter rods are characterized by a mixture of (nano)-crystals and amorphous matrix. Upon heating, the pre-existing nuclei grow, without forming new crystalline phases. The magnetic properties are characteristic for soft magnetic materials. Despite that several crystalline magnetic phases can be identified in the as-cast samples, only one single magnetic transition prior to complete crystallization could be identified upon heating. The values for saturation magnetization and for Curie temperature are relatively close for all samples. The initial permeability of the Cu containing samples seems to be higher than that for the fully amorphous [(Fe0.5Co0.5)0.75Si0.05B0.20]96Nb4 alloy. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.