Magnetic and electrical properties of iron-nickel-chromium-metalloid glasses

The magnetic and electrical properties of amorphous (Fe1-xNix)78- yCrySi10B12 alloys have been measured between 4.2 and 300 K. Alloys with x0.9 and y=5 order ferromagnetically. High-field magnetization measurements show saturation in moderate fields suggesting a relatively high value of magnetic anisotropy which was estimated to be K106 erg/cm3. The magnetization at low temperatures follows a T32 law leading to a spin-wave stiffness coefficient D90 meV 2. The x=1, y=5 alloy behaves like a "cluster glass" with a cluster ordering temperature around 20 K. Resistivity measurements show minima at low temperatures which can be explained with a modified Kondo mechanism. The resistivity maximum which appears around the cluster ordering temperature in Ni73Cr5Si10B12 is associated with a spin freeze-out of the Kondo effect due to local moments on Cr atoms.