Effect of Weak Magnetic Intergranular Phase on the Coercivity in the HDDR Nd-Fe-B Magnet

M. LIU, G. B. HAN, R. W. GAO

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DOI: 10.4236/jemaa.2009.14038                

Abstract

Assuming that intergranular phase (IP) existing between adjacent grains is a weak magnetic phase, we study the effect of IP on the coercivity in the HDDR Nd-Fe-B magnet. The results indicate that the coercivity increases with the increasing IP’s thickness d, but decreases with increasing its anisotropy constant K1(0). When the structure defect thickness r0 =6nm, d=1nm and K1(0)=0.15K1 (K1 is the normal anisotropy constant in the inner part of a grain), our calculated coercivity is in agreement with available experimental data.

Keywords

HDDR Nd-Fe-B Magnet, Intergranular Phase, Coercivity

Conflicts of Interest

The authors declare no conflicts of interest.

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