Properties of mechanically alloyed Fe100-xCrx powder mixtures:: Magnetic measurements

Magnetic measurements are reported on iron and chromium powder mixtures, obtained by mechanical alloying (MA) over the whole concentration range. Magnetization measurements under high and low magnetic field were performed in order to characterize the influence of the nanostructure on magnetic properties. Magnetic results for MA FeCr powders can be interpreted, in agreement with previous Mossbauer results at 300 K, taking into account two contributions: a contribution associated with the FeCr nanograin core and a contribution associated with the weakly magnetic disordered intergranular zone. In common with bulk FeCr alloys, MA FeCr powders seem to preserve a spin-glass-like (SGL) behavior, but over a greater range of composition depending on how they are made; the higher the grain boundary fraction, the wider the SGL domain and the lower the freezing temperature. (c) 2005 Elsevier B.V. All rights reserved.