窒素分布の改善によるNdFe₁₁TiN_x系磁石粉末の磁気特性の最大化

抄録

The effect of nitrogen distribution on the magnetic properties for the NdFe₁₁TiN_x powder was investigated. In case of the heat treatment under a constant pressure of nitrogen gas, the nitrogen distribution in the powder showed the gradient from the surface to the core, so that the saturation magnetization was relatively low (137-146 emu/g). In order to solve the gradient of nitrogen distribution, switching of the atmosphere from nitrogen to argon gas during the heat treatment was adopted. The nitrogen distribution was improved to be averaged in the powder. As a result, the saturation magnetization of the newly processed powder increased to about 155 emu/g (1.48 T). This process would be effective for the homogenization of the nitrogen distribution in the NdFe₁₁TiN_x powder.