	US 12,494,322 B2
	Preparation method for anisotropic Nd₂Fe₁₄β/α-Fe bulk nanocrystalline composite permanent magnet material
Xiaohong Li, Qinhuangdao (CN); Jinyi Wang, Qinhuangdao (CN); Jianyuan Kou, Qinhuangdao (CN); Peng Chen, Qinhuangdao (CN); Yan Zheng, Qinhuangdao (CN); Li Lou, Qinhuangdao (CN); and Xiangyi Zhang, Qinhuangdao (CN)
Assigned to Yanshan University, Qinhuangdao (CN)
Filed by Yanshan University, Qinhuangdao (CN)
Filed on Jun. 23, 2025, as Appl. No. 19/245,653.
Application 19/245,653 is a continuation of application No. PCT/CN2024/102885, filed on Jul. 1, 2024.
Claims priority of application No. 202310828366.7 (CN), filed on Jul. 7, 2023.
Prior Publication US 2025/0316419 A1, Oct. 9, 2025
Int. Cl. H01F 41/02 (2006.01); B22F 3/02 (2006.01); B22F 3/18 (2006.01); B22F 9/00 (2006.01); B22F 9/04 (2006.01); C22C 33/04 (2006.01); C22C 38/00 (2006.01); C22C 38/16 (2006.01); H01F 1/057 (2006.01)

CPC H01F 41/0266 (2013.01) [B22F 3/02 (2013.01); B22F 3/18 (2013.01); B22F 9/008 (2013.01); B22F 9/04 (2013.01); C22C 33/04 (2013.01); C22C 38/002 (2013.01); C22C 38/005 (2013.01); C22C 38/16 (2013.01); H01F 1/057 (2013.01); B22F 2009/043 (2013.01); B22F 2301/355 (2013.01); B22F 2998/10 (2013.01); B22F 2999/00 (2013.01)]

15 Claims

1. A preparation method for an anisotropic Nd₂Fe₁₄B/α-Fe bulk nanocrystalline composite permanent magnet material, comprising the following steps:

step 1. preparing a master alloy;

step 2. crushing the master alloy prepared in the step 1 into bulks, and preparing amorphous ribbons by means of a melt rapid quenching method;

step 3. grinding the amorphous ribbons obtained in the step 2 to obtain amorphous powder;

step 4. cold-pressing the powder obtained in the step 3 into bulks; and

step 5. placing the bulks obtained in the step 4 into a stainless steel mold, heating and then rolling the bulks; wherein

the stainless steel mold is of a plate-shaped structure, and a chamber for accommodating the bulks is formed in the stainless steel mold in a thickness direction thereof.