Title:
Ｎｄ－Ｆｅ－Ｂ系磁性体及びその製造方法
Document Type and Number:
Japanese Patent JP7325921
Kind Code:
B2
Abstract:
The invention relates to the technical field of sintered type NdFeB permanent magnets, in particular to a low-cost rare earth magnet and manufacturing method. There is provided a method of preparing a high-coercivity sintered NdFeB magnet including cerium comprising the following steps:(S1) Providing alloy flakes composed of RxT(1-x-y-z)ByMz wherein R is at least one of Nd, Pr, Ho, and Gd; T is at least one of Fe and Co; and M is at least one of Mg, Ti, Zr, Nb, and Mo; and x, y, and z are 28.0wt% ≤ x ≤ 33.0wt%, 0.8wt% ≤ y ≤ 1.2wt%, and 0wt% ≤ z ≤ 3.0wt%;(S2) Mixing the alloy flakes, a low melting point powder, and a lubricant, then subjecting the mixture to a hydrogen embrittlement process followed in this order by pulverizing the process product to an alloy powder by jet milling, magnetic field orientation molding of the alloy powder to obtain a blank, sintering and aging treatment the blank, and cutting the obtained sintered NdFeB magnet into the desired shape, wherein the low melting point powder is at least one of CeαAl100-α with 90≤α≤99, CeβCu1-β with 80≤β≤99, and CeγGa1-γ with 80≤γ≤99 and wherein a content of the Ce in the mixture is in the range of 1 to 10 wt% based on a total weight of the alloy flakes and the low melting point powder;(S3) Coating a film composed of a diffusion source of formula R1xR2yHzM1-x-y-z on the sintered NdFeB magnet, wherein R1 is at least one element of Nd and Pr; R2 is at least one element of Ho and Gd; H is at least one element of Tb and Dy; M is at least two elements of Al, Cu, Ga, Ti, Co, Mg, Zn, and Sn; and x, y, and z are 5.0wt% < x < 50.0wt%, 0wt% < y ≤ 15.0wt%, and 30.0wt% ≤ z ≤ 90.0wt%; and(S4) Performing a diffusion heat treatment so as to diffuse the diffusion source into the sintered NdFeB magnet, followed by aging the sintered NdFeB magnet to obtain the low-cost rare earth magnet.
Inventors:
Royal tradition
Yang Kun Kun
Jin Jie
Kokai
Yang Kun Kun
Jin Jie
Kokai
Application Number:
JP2022139853A
Publication Date:
August 15, 2023
Filing Date:
September 02, 2022
Export Citation:
Assignee:
Smokedai Tosei Magnetic Materials Co., Ltd.
International Classes:
H01F1/057; B22F1/00; B22F1/05; B22F3/00; B22F3/24; B22F9/04; B22F9/08; C22C28/00; C22C33/02; C22C38/00; C22C45/00; H01F41/02
Domestic Patent References:
| JP2018182299A | ||||
| JP2023045934A | ||||
| JP2018104818A | ||||
| JP2022516380A | ||||
| JP2011060975A | ||||
| JP2022031605A | ||||
| JP2021533557A |
Foreign References:
| US20220059262 | ||||
| CN108335897B | ||||
| CN108922768B | ||||
| CN111916285A | ||||
| US20210233689 |
Attorney, Agent or Firm:
Kenji Hidaka