晶粒间界相及结构缺陷对HDDR粘结磁体矫顽力的影响  

Dependence of coercivity on the intergranular phase and structure defect for HDDR bonded magnet

作　　者：刘敏[1] 古爱琼[1] 高汝伟[2] 

机构地区：[1]惠州学院电子科学系,广东516007 [2]山东大学物理学院,山东250100

出　　处：《原子与分子物理学报》2011年第5期953-958,共6页Journal of Atomic and Molecular Physics

基　　金：惠州学院博士科研启动项目(C510.0205)

摘　　要：本文根据氢化/歧化/脱氢/重组(HDDR)Nd-Fe-B磁粉晶粒边界微结构的特点,建立了缺陷区内的磁晶各向异性常数K′_1及交换积分常数A′_1的双变量连续变化模型,研究了晶粒间界相厚度d及晶粒表面结构缺陷厚度r_0对磁体矫顽力的影响.结果表明:晶粒表面各向异性常数K_1(0)、交换积分常数A_1(0)及r_0取不同值时,磁体的矫顽力H_c均随d增加而增大.K_1(0)和A_1(0)取确定值时,相同的d值对应的H_c随r_0的增大而上升.r_0和d取确定值时,H_c随K_1(0)或A_1(0)的减小而增大.当d为1nm,r_0在(2～5)nm范围内,A_1(0)和K_1(0)的值分别在A_1和K_1值的(0.6～0.7)范围内变动时,计算的矫顽力与实验值符合得很好.According to the microstructure of HDDR （hydrogenation, disproportionation, desorption and recombination） Nd--Fe--B magnetic powders grains, the model of double continuous variations was proposed for the anisotropy constant K＇1 and the exchange integral A＇1 in defect region. The dependence of coericivity of magnet on the intergranular phase thickness d and the structure defect thickness r0 was studied. The results showed that the coercivity, Hc, increases as d increases when the thickness r0, the anisotropy constant K1 （0） at the grain surface and the exchange integral constant A1 （0） take different values. When K1 （0） and A1 （0） are fixed, Hc enhances as r0increases for the same d. On the contrary, for the fixed r0 and d, Hc decreases with increasing KI （0） or A1 （0）. The calculated coercivity is in good agreement with experimental results given by others when d takes 1nm, r0 is in the rang of （2-5） nm, A1 （0） and K1 （0） change in the range of （0.6-0.7） of A1 and K1 , respectively.

关 键 词：粘结磁体 双变量模型 微结构 矫顽力 

分 类 号：O482.54[一般工业技术—材料科学与工程] TM273[理学—固体物理]