High stability of magnetic parameters in Fe–Al nanocomposite powders

The structural and magnetic properties of Fe 75 Al 25 nanosystem prepared by high energy ball milling for 15 h milling time have been studied. Structural analysis shows the formation of distinct Fe–Al portions with Al at grain boundaries, indicating that Fe–Al nanocomposite formation is favored over alloying due to the formation of diffusion hindering Fe–Al phase at grain boundaries. The saturation magnetization (Ms) of the nanocomposite at 8 nm grain size is 117 emu/g (i.e. 55 % that of pure Fe). The Curie temperature (T C ) 1053 K matches the value of pure bcc α -Fe. M–H curves recorded after M–T studies are the same as before indicating the extreme stability of this system against high temperatures. Low temperature M–T measurements and room temperature remanence measurements show that interparticle interactions are demagnetizing kind and dipolar in nature.