A Study of Two- Phase Nanocrystalline Nd_(8.5)Fe_(75)Co_5Cu_1Zr_3Nb_1B_(6.5) Permanent Magnet

摘要

Nanocrystalline Nd_(8.5)Fe_(75)Co_5Cu_1Zr_3Nb_1B_(6.5) ribbons were prepared by melt-spun (18 m·s~(-1)) and subsequent heat treatment (670℃/4 min). Excellent magnetic properties of the bonded magnet were achieved as follows: B_r = 0.68 T (6.8 kGs), _JH_c = 620.3 kA·m~(-1)(7.8 kOe), (BH)_(max) = 74 kJ·m~(-3)(9.3 MGOe). The results of TEM photomicrographs confirm that the appearance of α-Fe phase is earlier than that of Nd_2Fe_(14)B phase during crystallization process. The addition of Cu and Zr elements shows to be advantageous to the improvement of an intrinsic coercivity and squareness of hysteresis loop, as well as energy product.