Evidence of dipolar magnetic field in mechanically alloyed Fe50Al50 samples

Powders of mechanically alloyed Fe50Al50 were milled during 72 h and separated at different mean particle sizes as well as characterized based on their structure and magnetic properties. All the samples showed Fe–Al BCC and α-Fe phases as well as the same nanostructure. Fe50Al50 powders were found to be ferromagnetic at room temperature with a mean hyperfine magnetic field that increases with increasing particle size. The origin of these magnetic behaviors is attributed to the increment of magnetic dipolar interactions between the magnetic moment of each particle and the field produced by other magnetic moments of their surrounded particles. This field also increases as the particle size increases.

► The big size distribution of mechanically alloyed FE50Al50 powders was avoided by sieving to different meshes.
► Show that the mean hyperfine magnetic field has the contribution of the dipolar magnetic field.
► Show that this dipolar magnetic field affects the irreversible temperature and the coercive field of the samples.