BONDED La(Fe,Si)13-BASED MAGNETOCALORIC MATERIAL AND PREPARATION AND USE THEREOF

• US 20150047371A1
• Filed: 05/17/2012
• Published: 02/19/2015
• Est. Priority Date: 11/22/2011
• Status: Active Grant

• Current Assignee: Institute of Physics Chinese Academy of Sciences (Chinese Academy of Sciences), Hubei Quanyang Magnetic Materials Manufacturing Co., Ltd
• Original Assignee: Institute of Physics Chinese Academy of Sciences (Chinese Academy of Sciences), Hubei Quanyang Magnetic Materials Manufacturing Co., Ltd
• Inventors: Hu, Fengxia, Chen, Ling, Bao, Lifu, Wang, Jing, Shen, Baogen, Sun, Jirong, Gong, Huayang
• Granted Patent: US 10,096,411 B2
• Time in Patent Office: Days
• US Class Current: 62/3.1
• CPC Class Codes: F25B 21/00 Machines, plants or systems, using electric or magnetic effects
• CPC Class Codes: F25B 2321/002 by using magneto-caloric effects
• CPC Class Codes: H01F 1/015 Metals or alloys

Abstract

Provided is a high-strength, bonded La(Fe, Si)₁₃-based magnetocaloric material, as well as a preparation method and use thereof. The magnetocaloric material comprises magnetocaloric alloy particles and an adhesive agent, wherein the particle size of the magnetocaloric alloy particles is less than or equal to 800 μm and are bonded into a massive material by the adhesive agent; the magnetocaloric alloy particle has a NaZn₁₃-type structure and is represented by a chemical formula of La_1-xR_x(Fe_1-p-qCo_pMn_q)_13-ySi_yA_α, wherein R is one or more selected from elements cerium (Ce), praseodymium (Pr) and neodymium (Nd), A is one or more selected from elements C, H and B, x is in the range of 0≦x≦0.5, y is in the range of 0.8≦y≦2, p is in the range of 0≦p≦0.2, q is in the range of 0≦q≦0.2, α is in the range of 0≦α≦3.0. Using a bonding and thermosetting method, and by means of adjusting the forming pressure, thermosetting temperature, and thermosetting atmosphere, etc., a high-strength, bonded La(Fe, Si)₁₃-based magnetocaloric material can be obtained, which overcomes the frangibility, the intrinsic property, of the magnetocaloric material. At the same time, the magnetic entropy change remains substantially the same, as compared with that before the bonding. The magnetic hysteresis loss declines as the forming pressure increases. And the effective refrigerating capacity, after the maximum loss being deducted, remains unchanged or increases.

Claims

1. A high-strength, bonded La (Fe, Si)₁₃-based magnetocaloric material, comprising magnetocaloric alloy particles and an adhesive agent, wherein, the magnetocaloric alloy particles have a particle size in the range of ≦

800 μ

m and are bonded into a massive material by the adhesive agent;

wherein, the magnetocaloric alloy particles have a NaZn₁₃-type structure and are represented by a chemical formula;

La_1-xR_x(Fe_1-p-qCo_pMn_q)_13-ySi_yA_α

,

wherein,

R is one or more selected from elements Ce, praseodymium (Pr) and Nd,

A is one or more selected from elements C, H and B,

x is in the range of 0≦

x≦

0.5,

y is in the range of 0.8≦

y≦

2,

p is in the range of 0≦

p≦

0.2,

q is in the range of 0≦

q≦

0.2,

α

is in the range of 0≦

α

≦

3.0.

2. The magnetocaloric material according to claim 1, wherein, relative to 100 parts by weight of the magnetocaloric alloy particles, the adhesive agent is in an amount of 1˜

10 parts by weight, preferably 2˜

5 parts by weight.

3. The magnetocaloric material according to claim 1, wherein, the adhesive agent is selected from one or more of epoxide-resin glue, polyimide adhesive, urea resin, phenol-formaldehyde resin and diallyl phthalate, preferably selected from one or both of epoxide-resin glue and polyimide adhesive.

4. The magnetocaloric material according to claim 1, wherein, the magnetocaloric alloy particles have a particle size in the range of 15˜

800 μ

m, preferably 15˜

200 μ

m.

5. The magnetocaloric material according to claim 1, wherein, the magnetocaloric alloy particles is represented by a chemical formula:

La_1-xR_x(Fe_1-pCo_p)_13-ySi_yA_α

, wherein

R is selected from one or more of elements Ce, Pr and Nd,

A is selected from one, two or three of elements H, C and B,

x is in the range of 0≦

x≦

0.5,

y is in the range of 1≦

y≦

2,

p is in the range of 0≦

p≦

0.1,

α

is in the range of 0≦

α

≦

2.6.

6. A method for preparing a magnetocaloric material according to claim 1, comprising the steps of:

1) formulating raw materials according to the chemical formula, or formulating raw materials other than hydrogen according to the chemical formula where A includes hydrogen element;

2) placing the raw materials formulated in step

     1) in an arc furnace, vacuuming and purging the furnace with an inert gas, and smelting the materials under the protection of an inert gas so as to obtain alloy ingots, wherein the inert gas is preferably argon gas;

3) vacuum annealing the alloy ingots obtained in step

     2) and then quenching the alloy ingots in liquid nitrogen or water, or furnace cooling the alloy ingots to room temperature, so as to obtain the magnetocaloric alloys La_1-xR_x(Fe_1-p-qCo_pMn_q)_13-ySi_yA_α

having a NaZn₁₃-type structure;

4) crushing the magnetocaloric alloys obtained in step

     3) so as to obtain magnetocaloric alloy particles with a particle size of ≦

800 μ

m;

5) mixing an adhesive agent with the magnetocaloric alloy particles obtained in step

     4) evenly, press forming and solidifying the mixture into a massive material;

wherein, when A in the chemical formula includes hydrogen element, the solidification in step

     5) is performed in hydrogen gas.

7. The method according to claim 6, wherein, in step 5), the adhesive agent is mixed with the magnetocaloric alloy particles by a dry or wet mixing method;

wherein the dry mixing method includes the step of mixing the pulverous adhesive agent as well as its curing agent and accelerating agent with the magnetocaloric alloy particles evenly; and

the wet mixing method includes the steps of dissolving the adhesive agent as well as its curing agent and accelerating agent in an organic solvent to obtain a glue solution, adding the magnetocaloric alloy particles to the glue solution, mixing evenly and drying the mixture.

8. The method according to claim 6, wherein, in step 5), the press forming is carried out under a compressing pressure of 100 MPa˜

20 GPa, preferably 0.1˜

2.5 GPa for a compressing period of 1˜

120 mins, preferably 1˜

10 mins.

9. The method according to claim 6, wherein, in step 5), the solidification is performed in an inert gas or in vacuum;

and the solidification condition includes a solidification temperature of 70˜

250°

C., preferably 100˜

200°

C., a solidification period of 1˜

300 mins, preferably 10˜

60 mins, an inert gas pressure of 10<sup>−

2</sup> Pa˜

10 MPa or a vacuum degree of <

1 Pa;

where A in the chemical formula includes hydrogen element, the solidification in step

     5) is performed in hydrogen gas; and

the solidification condition includes a solidification temperature of 70˜

250°

C., preferably 100˜

200°

C., a solidification period of 1˜

300 mins, preferably 10˜

60 mins, and a hydrogen gas pressure of 10<sup>−

2</sup> Pa˜

10 MPa.

10. The method according to claim 6, wherein, the raw materials La, R are commercially available elementary rare earth elements and/or industrial-pure LaCe alloy and/or industrial-pure LaCePrNd mischmetal;

preferably, where A includes carbon and/or boron element(s), the carbon and/or boron are provided by FeC and/or FeB alloy(s), respectively

11. The method according to claim 6, wherein, the step 2) comprises the steps of placing the raw material formulated in step 1) into an arc furnace;

vacuuming the arc furnace to reach a vacuum degree less than 1×

10<sup>−

2</sup>Pa;

purging the furnace chamber with an argon gas having a purity higher than 99 wt. % once or twice;

then filling the furnace chamber with the argon gas to reach 0.5-1.5 atm; and

arcing;

so as to obtain the alloy ingots;

wherein each alloy ingot is smelted at 1500-2500°

C. for 1-6 times repeatedly;

the step

     3) comprises the steps of annealing the alloy ingots obtained in step

     2) at 1000-1400°

C., with a vacuum degree less than 1×

10<sup>−

3</sup> Pa, for 1 hour-60 days;

then quenching the alloy ingots in liquid nitrogen or water, or furnace cooling the alloy ingots to room temperature.

12. A magnetic refrigerator, comprising a magnetocaloric material according to claim 1.

13. Use of a magnetocaloric material according to claim 1 in the manufacture of refrigeration materials.

14. A magnetic refrigerator, comprising a magnetocaloric material prepared by a method according to claim 6.

15. Use of a magnetocaloric material prepared by a method according to claim 6 in the manufacture of refrigeration materials.