Magnetic properties enhancement by microstructure refinement for Ti doped α-Fe/Nd2Fe14B alloys

In this work, the correlation between the microstructure and magnetic properties for (Nd_0.8Ce_0.2)_1.6Fe₁₂Co₂BTi_x (x = 0~2 wt%) alloys are investigated. The results reveal that proper Ti addition tends to result in relevant improvements of magnetic properties by microstructure refinement, especially in the coercivity H_cj. It is shown that the enhanced maximum energy products (BH)_max of 14.5 MGOe and coercivity H_cj of 6.63 kOe have been obtained with Ti content at x = 0.5 and x = 1.5, respectively. The magnetic domain structures show that the Ti-doped alloy with the regular and homogeneous domains structure with stronger contrast is in charge of the better magnetic performance and give the evidence for the increase of domain width D_w and domain wall energy γ_w resulting in a strong increase of exchange coupling interaction.