Melt spun and suction cast Nd-Fe-Co-B-Nb hard magnets with high Nd contents

作者：Cui X H; Liu Z W^*; Zhong X C; Yu H Y; Zeng D C

来源：Journal of Applied Physics, 2012, 111(7): 07B508.

DOI：10.1063/1.3672859

• After-heat treatment
• Amorphous structures
• Bulk metallic glass
• Crystalline structure
• Glass forming ability
• Hard magnetic behavior
• Melt-spun ribbons
• Nanocomposite magnets

Nd-Fe-Co-B-Nb alloys with Nd contents of 9 9.5 at% were prepared by melt spinning and suction casting. It was found from the melt spun ribbon samples that Nb addition enhanced the glass forming ability and Co addition improved the thermal stability. Larger values of J(r) and (BH)(max) were obtained for the ribbon samples than for the bulk ones due to the finer crystalline structure in the former. Nanocrystallite with amorphous structure was found in the suction cast rod samples. The as-cast Nd9Fe71.5B15.5Nb4 rod in a diameter of 2 mm exhibited the best hard magnetic behavior. A remanence of 0.59 T, a coercivity of 1154 kA/m, and a maximum energy product of 54.2 kJ/m(3) have been obtained after heat treatment. The distribution of nonmagnetic FeNb phase plays a key role in the improvement of coercivity. Current work suggests that large size Nd2Fe14B/Fe3B nanocomposite magnets with high Nd contents and good magnetic properties can be obtained using a nanocrystalline precursor instead of bulk metallic glass.

• 出版日期2012-4-1
• 单位华南理工大学