Magnetic properties and magnetic reversal process of exchange-coupled Nd2Fe14B/alpha ''-Fe16N2 bilayers

摘要

The hysteresis loops and the magnetic reversal process of exchange-coupled Nd2Fe14B/alpha ''-Fe16N2 bilayers, with a deviation angle of easy axis beta from the applied magnetic field direction and different thicknesses of soft phase were investigated using the object-oriented micromagnetic framework. Results show that a deviation of easy axis in Nd2Fe14B/alpha ''-Fe16N2 bilayers can affect the magnetic properties and significantly decrease the energy product and coercivity. The remanence increases, whereas the coercivity of the bilayers drops monotonically, with the increase in thickness of the soft magnetic layer (L-s). A well-oriented bilayer with L-s = 4 nm exhibits the largest maximum energy product (i.e., 881.67 kJ/m(3)), which is larger than that of the other common exchange spring materials that we calculated. Therefore, the proposed nanocomposite magnet is one of the most promising exchange spring systems to achieve maximum energy product. Published by AIP Publishing.