Process Development for Synthesizing FeCoN-Based Magnetic Materials

To improve the magnetic properties of FeCo alloys, the formation conditions of nitriding phases like ${\alpha}^{\prime\prime}$ and ${\gamma}^{\prime}$ with excellent magnetic properties were investigated. The conditions of gas nitriding and the grain size of a $\mathbf{100}\ {\mu} \mathbf{m}$ thick FeCo foil were investigated. Then, by using a material with a small grain size, adjusting the gas nitriding temperature and ammonia gas concentration, and nitriding only the diffusion layer without forming a nitriding layer, a prospect was obtained that nitrogen was uniformly introduced into the entire depth of the foil with only a single phase of ${\gamma}^{\prime}$ phase. We expect that by quenching this film material above the austenitic transformation temperature, the possibility of ${\alpha}^{\prime}$ formation can be investigated in the future.