MnAl alloy and production method thereof

Patent metadata

Field	Value
Publication number	US-11441218-B2
Application number	US-201716475439-A
Country	US
Kind code	B2
Filing date	Dec 27, 2017
Priority date	Jan 5, 2017
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

An object of the present invention is to provide a Mn-based alloy exhibiting metamagnetism over a wide temperature range. A Mn-based alloy according to the present invention is a MnAl alloy having metamagnetism. The metamagnetism refers to a property in which magnetism undergoes transition from paramagnetism or antiferromagnetism to ferromagnetism by a magnetic field. In the MnAl alloy, an antiferromagnetic state is adequately stable, so that by imparting AFM-FM transition type metamagnetism (the type of metamagnetism undergoing transition from antiferromagnetism to ferromagnetism), it is possible to obtain metamagnetism over a wide temperature range, particularly, over a temperature range of −100° C. to 200° C.

First claim

What is claimed is:

1. A MnAl alloy exhibiting metamagnetism,
wherein a composition of the MnAl alloy is expressed by Mn b Al 100-b and 45≤b≤50,
wherein the MnAl alloy contains crystal grains having a τ-MnAl phase, and
wherein a composition of the τ-MnAl phase is expressed by Mn a Al 100-a and 48≤a≤55.

2. The MnAl alloy as claimed in claim 1 ,
wherein a magnetic structure of the τ-MnAl phase has an antiferromagnetic structure in a non-magnetic field state.

3. The MnAl alloy as claimed in claim 2 , wherein the composition of the τ-MnAl phase is expressed by Mn a Al 100-a and 50<a<55.

4. The MnAl alloy as claimed in claim 1 , wherein an order parameter of the τ-MnAl phase is 0.85 or more.

5. The MnAl alloy as claimed in claim 1 , wherein the MnAl alloy exhibits the metamagnetism over a temperature range of −100° C. to 200° C.

6. The MnAl alloy as claimed in claim 1 , wherein the MnAl alloy is in a powder form.

7. The MnAl alloy as claimed in claim 6 , wherein the MnAl alloy has a predetermined shape by molding a powdery MnAl alloy.

8. An electronic component including the MnAl alloy as claimed in claim 1 .

9. A method for manufacturing the MnAl alloy of claim 1 , the method comprising:
depositing the MnAl alloy by electrolyzing molten salt containing a Mn compound and an Al compound; and
applying heat treatment to the MnAl alloy at a temperature of 400° C. or more and less than 600° C.

10. A MnAl alloy formed by subjecting Mn and Al to temperature-controlled electrolysis and heat treatment that result in the MnAl alloy exhibiting metamagnetism.

Assignees

• Tdk Corp

Inventors

• SATOH Suguru
• Irie Shuichiro
• Miura Yasunao

Classifications

• B22F1/142

  Thermal or thermo-mechanical treatment · CPC title

• B22F9/14

  using electric discharge · 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

• C22F1/16 Primary

  of other metals or alloys based thereon · CPC title

• C22C21/00

  Alloys based on aluminium · CPC title