Structural and magnetic properties of Fe100-xTix nanocrystalline powders prepared by planetary ball mill process

Abstract

Nanocrystalline Fe_100-xTi_x (x = 0–25) powders are synthesized via a mechanical alloying process, and investigated their properties with varying milling times (t_mill) and compositions (x). Structural studies revealed that Fe sites were substituted by Ti, resulting in the formation of nonequilibrium Fe(Ti) solid solutions with large dislocation density (1.2 × 10¹⁷m⁻²-2.2 × 10¹⁷m⁻²) and fine crystallites (∼10 nm). The determined lattice constant reveals significant disorders. Magnetic properties illustrate that coercivity (H_C) increases up to a certain t_mill and then decreases but increases progressively with x. This could be attributed to the development of dislocation density, grain boundary, and fine nanocrystals. Saturation magnetization (M_S) diminishes with increasing t_mill and Ti. H_C and M_S were found to be ∼0.40–4.01 kA/m and ∼2.156–1.291T, respectively, in the Fe_100-xTi_x. These results are quite useful for understanding the effect of Ti in Fe_100-xTi_x and possible applications in electric transformer cores, as soft magnetic inclusions in hard/soft exchange coupled spring permanent magnets, etc.