Title:
MICRO POWDER FOR PREPARING NEODYMIUM-IRON-BORON PERMANENT MAGNET MATERIAL, METHOD FOR PREPARING POWDER BY TARGET-TYPE JET MILLING, AND POWDER
Document Type and Number:
WIPO Patent Application WO/2018/113555
Kind Code:
A1
Abstract:
Micro powder for preparing a neodymium-iron-boron permanent magnet material, a method for preparing powder by means of target-type jet milling, and jet-milled powder. The sphericity of the micro powder is larger than or equal to 90%, and the particle powder adhesion is smaller than or equal to 10%. In the method for preparing powder by means of target-type jet milling, the relationship among the diameter A of a target, the diameter B of a side nozzle, and the distance C between the target and the side nozzle is: A/B = m×(C/A+B), wherein the value range of m is 1-7, and the airflow jet velocity of the side nozzle is 320-580 m/s. The relationship between the diameter F of a classifying wheel and the diameter A of the target is: F = p×A, wherein the value range of p is 3-6. The jet-milled powder obtained by the method above consists of ultra-fine powder and the micro powder. The ratio of the mass of the ultra-fine powder to the total mass of the jet-milled powder is smaller than or equal to 0.5%. The particle size of the micro powder is uniform in distribution and small in range; the micro powder has low nitrogen content and is applicable to mass production of high-quality sintered neodymium-iron-boron permanent magnet material. Moreover, the powder obtained by the target-type jet milling method contains no unmilled material, and thus saves a follow-up process.
Inventors:
CHEN GUOAN (CN)
FANG BIN (CN)
SUN LIBAI (CN)
ZHAO YUGANG (CN)
FANG BIN (CN)
SUN LIBAI (CN)
ZHAO YUGANG (CN)
Application Number:
PCT/CN2017/115679
Publication Date:
June 28, 2018
Filing Date:
December 12, 2017
Export Citation:
Assignee:
SANVAC BEIJING MAGNETICS CO LTD (CN)
BEIJING ZHONG KE SAN HUAN (CN)
BEIJING ZHONG KE SAN HUAN (CN)
International Classes:
B22F1/00; B22F1/052; B22F1/065
Foreign References:
| CN103219117A | 2013-07-24 | |||
| CN101767200A | 2010-07-07 | |||
| CN103785845A | 2014-05-14 | |||
| CN104289713A | 2015-01-21 | |||
| JPS6283401A | 1987-04-16 | |||
| US4783215A | 1988-11-08 |
Attorney, Agent or Firm:
BEIJING LAWSING IP FIRM (CN)
Download PDF: