Micromagnetic simulation of magnetization reversal process using MFM image

This research aims to study the hysteresis loop and magnetization reversal process in Nd₂Fe₁₄B samples with grain size varying from 300 to 1000 nm using magnetic force microscope image modelling. It is shown that the remanence enhances as the saturation magnetization of amorphous grain boundary phase increases. The magnetization, however, drop down rapidly because of the bad exchange coupling interaction between two phases which lead to coercivity reduction. Thus, the non-magnetic grain boundary phase is beneficial to increase the coercivity. Distribution of magnetic moment is also discussed.