Method for preparing metal powder, and metal powder

Patent metadata

Field	Value
Publication number	US-11721460-B2
Application number	US-201716318478-A
Country	US
Kind code	B2
Filing date	Oct 18, 2017
Priority date	Nov 8, 2016
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

A method for preparing a metal powder includes preparing a mixture by mixing a fluoride of a group 1 element, a fluoride of a group 2 element or a transition metal fluoride, with neodymium oxide, boron, iron, and a reducing agent; and heating the mixture at a temperature of 800° C. to 1100° C.

First claim

The invention claimed is:

1. A method for preparing a metal powder, comprising:
preparing a mixture by mixing neodymium oxide, boron, iron, and a reducing agent with at least one of a fluoride of a group 1 element, a fluoride of a group 2 element or a transition metal fluoride;
molding the mixture to prepare a molded body after the preparing of the mixture,
heating the molded body to a temperature of more than 800° C. to 1100° C. under an inert gas atmosphere; and
forming the metal powder,

wherein the metal powder is Nd 2 Fe 14 B,
wherein the reducing agent is at least one of calcium, calcium hydride, or calcium carbide, and
wherein a total content of the fluoride of the group 1 element, the fluoride of the group 2 element or the transition metal fluoride is 1 wt % to 10 wt % of the metal powder.

2. A method for preparing a metal powder, comprising:
preparing a mixture by mixing neodymium oxide, boron, iron, and a reducing agent with at least one of a fluoride of a group 1 element, a fluoride of a group 2 element or a transition metal fluoride;
heating the mixture to a temperature of 800° C. to 1100° C. under an inert gas atmosphere; and
forming the metal powder,
wherein the metal powder is Nd 2 Fe 14 B, and
wherein the reducing agent is at least one of calcium, calcium hydride, or calcium carbide, and
wherein the method does not include a pulverizing process,
and the method does not include a surface treating process.

3. The method for preparing the metal powder of claim 1 , wherein
the heating of the molded body to the temperature of more than 800° C. to 1100° C. under the inert gas atmosphere is performed for 30 minutes to 6 hours.

4. The method for preparing the metal powder of claim 1 , wherein
the metal powder has a size of 0.5 μm to 10 μm.

5. The method for preparing the metal powder of claim 1 , wherein
the fluoride of the group 1 element is at least one of NaF, LiF, KF, or RbF.

6. The method for preparing the metal powder of claim 1 , wherein
the fluoride of the group 2 element is at least one of CaF 2 , MgF 2 , SrF 2 , BaF 2 , or RaF 2 .

7. The method for preparing the metal powder of claim 1 , wherein
the transition metal fluoride is at least one of AlF 3 , CoF 2 , CrF 3 , FeF 2 , NiF 2 , or ZrF 4 .

8. The method for preparing the metal powder of claim 1 , wherein
the total content of the fluoride of the group 1 element, the fluoride of the group 2 element or the transition metal fluoride is 1 wt % to 5 wt % of the metal powder.

9. The method for preparing the metal powder of claim 1 , wherein
a fluoride insulating film is formed on a surface of the metal powder.

10. The method for preparing the metal powder of claim 1 , further comprising
pulverizing the molded body after the molded body is heated to the temperature of more than 800° C. to 1100° C.

11. The method of claim 1 , wherein the method does not include a surface treating process.

12. The method of claim 1 , wherein the metal powder is formed by a reduction-diffusion method.

Assignees

• Lg Chemical Ltd

Inventors

• In June Ho
• Kwon Soon Jae
• Choi Ik Jin
• Uh Hyoun Soo
• Park Jung Won
• Lim Byung Kyu
• Park Pum Suk

Classifications

• H01F1/0572 Primary

  with a protective layer · CPC title

• B22F1/06

  Metallic powder characterised by the shape of the particles (nanosized particles B22F1/054) · CPC title

• B22F1/16

  Metallic particles coated with a non-metal (coated with lubricating or binding agents or with organic material B22F1/10) · CPC title

• B22F9/04

  starting from solid material, e.g. by crushing, grinding or milling ({C22C1/1084 takes precedence}; crushing, grinding or milling, in general, see the relevant subclasses, e.g. B02C) · CPC title

• B22F9/20

  starting from solid metal compounds · CPC title