R2Fe14B型永磁材料中第二磁晶各向异性常数对反磁化过程的影响

针对低温下各向同性Pr₂Fe₁₄B永磁材料的最小形核场问题，用数值 计算法和近似解 析解研究了第二磁晶各向异性常数K₂对最小形核场的影响.研究发现，尽管对于 Nd₂ Fe₁₄B永磁材料一级近似的解析解与数值计算结果很接近，但是对于低温下各向 同性P r₂Fe₁₄B永磁材料则至少要用二级近似下的解析解才能与数值计算 结果相接近.用有 关最小形核场的计算结果很好地解释了低温时各向同性Pr₂Fe₁₄B永 磁材料的矫顽力与最小形核场的关系. 关键词： 第二磁晶各向异性常数 形核场 矫顽力

Effect of the second-order magnetocrystalline anisotropic constant on the magnetization reversal in R2Fe14B magnets

In this work, the dependence of the second-order magnetocrystalline anisotropic constant K₂ on the minimum nucleation field H^min_{n has been investigated by the numerical method and the analytical formulation under the second-order approximation. It is found that the contribution of K2 t o H ^minn is very large at low temperatures for isotropic Pr2}Fe₁₄B magnets. Although the value of H^min_{n for Nd2Fe14B can b e obt ained using the analytical formulation under the first-order approximation, the value of H^minn for Pr2Fe14B is achie ved using the formulation under the second-order approxiamtion. Using the obtained value of H^{minn, a good linear relation between coercivity and Hminn}} is found in the temperature range from 20 K to room temperature.