Rare earth-gallium material for magnetic refrigeration and preparation method thereof

A magnetic refrigeration and rare earth technology, applied in the field of rare earth-gallium materials and their preparation, can solve the problems of limited commercial application, low magnetic refrigeration capacity, etc.

Inactive Publication Date: 2011-03-30
INST OF PHYSICS - CHINESE ACAD OF SCI
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the magnetic refrigeration materials discovered in this temperature region mainly include rare earth element single crystals, polycrystalline materials, such as Nd, Er or Tm, and rare earth intermetallic compounds, such as ErCo 2 , DyAl 2 , RCoAl (R=Tb or Dy), TbCoC 2 or Ho 2 In et al., but because the magnetic refrigeration capacity of the above-mentioned magnetic refrigeration materials is still low, its commercial application is limited

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Rare earth-gallium material for magnetic refrigeration and preparation method thereof
  • Rare earth-gallium material for magnetic refrigeration and preparation method thereof
  • Rare earth-gallium material for magnetic refrigeration and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0032] According to a first embodiment of the present invention, a method for preparing ErGa is provided, comprising the following steps:

[0033] Step 1): weighing materials according to ErGa chemical formula (ie, atomic ratio), mixing commercially available rare earth metal Er with a purity higher than 99.9% and Ga raw materials, wherein Er is added in excess of 2% (atomic percentage);

[0034] Step 2): Put the prepared raw materials in step 1) into the electric arc furnace or induction heating furnace for vacuuming, when the vacuum degree reaches 2×10 -3 -3×10 -3 Pa, after cleaning with high-purity argon with a purity of 99.999% for 1-2 times, under the protection of high-purity argon at 1 atmosphere, repeatedly turn over and melt for 3-5 times, and the melting temperature is between 1500°C and 1700°C;

[0035] Step 3): Cool the cast alloy in a copper crucible, wrap the cast alloy with molybdenum foil, and seal it in a vacuum of 5×10 -5 In a Pa quartz tube, it was anneale...

Embodiment 2

[0044] According to a second embodiment of the present invention, a method for preparing HoGa is provided, comprising the following steps:

[0045] Step 1): weighing materials according to the HoGa chemical formula (ie atomic ratio), mixing commercially available rare earth metal Ho with a purity higher than 99.9% and Ga raw materials, wherein Ho is added in excess of 2% (atomic percentage);

[0046] Step 2): Put the prepared raw materials in step 1) into the electric arc furnace or induction heating furnace for vacuuming, when the vacuum degree reaches 2×10 -3 -3×10 -3 Pa, after cleaning with high-purity argon with a purity of 99.999% for 1-2 times, under the protection of high-purity argon at 1 atmosphere, turn and melt repeatedly for 3 times, and the melting temperature is between 1500°C and 1700°C;

[0047] Step 3): Cool the cast alloy in a copper crucible, wrap the cast alloy with molybdenum foil, and seal it in a vacuum of 5×10 -5 In a Pa quartz tube, it was annealed a...

Embodiment 3

[0055] According to a third embodiment of the present invention, a method for preparing DyGa is provided, comprising the following steps:

[0056] Step 1): weighing materials according to the chemical formula of DyGa (ie atomic ratio), mixing commercially available rare earth metal Dy with a purity higher than 99.9% and Ga raw materials, wherein Dy is excessively added by 4% (atomic percentage);

[0057] Step 2) and step 3) are identical with embodiment 1.

[0058] The room temperature X-ray diffraction spectrum line of this embodiment compound is as follows Figure 11 As shown, the results show that HoGa forms a single-phase CrB-type orthorhombic crystal structure, the space group is Cmcm, and its lattice parameter

[0059] The thermomagnetic (M-T) curve of present embodiment compound is as follows Figure 12 As shown, the Curie temperature T of DyGa can be determined from the M-T curve C for 115K. The compound of this example is in the T C The nearby magnetic entr...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a rare earth-gallium material for magnetic refrigeration. The rare earth-gallium material is a compound with the following general formula: RGa, wherein R is Dy, Ho or Er. In the rare earth-gallium material, the HoGa and ErGa both present a larger magnetic entropy change in adjacent regions of respective phase-transition temperature, thus the working temperature region is wide, and the rare earth-gallium material has larger magnetic refrigeration capability and good thermal and magnetism reversible property and is an ideal medium-temperature region refrigeration material.

Description

technical field [0001] The invention relates to magnetic materials, in particular to a rare earth-gallium material for magnetic refrigeration and a preparation method thereof. Background technique [0002] Traditional gas compression refrigeration technology has been widely used in various industries, but it has disadvantages such as low refrigeration efficiency, high energy consumption, and damage to the atmospheric environment. Compared with traditional gas compression refrigeration technology, magnetic refrigeration technology has significant advantages such as high efficiency, energy saving, environmental protection, and stable operation, and is known as a high-tech green refrigeration technology. Magnetic refrigeration refers to a new type of refrigeration technology that uses magnetic materials as the refrigerant. The moments tend to be arranged in an orderly manner, the magnetic entropy decreases, and heat is released to the outside; when the magnetization strength w...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H01F1/053C22C28/00C22C1/02C21D1/26C21D1/74C21D1/60C22F1/16
Inventor 陈静沈保根董巧燕胡凤霞孙继荣
Owner INST OF PHYSICS - CHINESE ACAD OF SCI
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap