Preparation method of rare earth-nickel-gallium material with colossal magnetic refrigeration capability

A magnetic refrigeration material and rare earth technology, which is applied in the field of rare earth-nickel-gallium materials and their preparation, can solve the problems of the magnetic refrigeration material decline in magnetic refrigeration capacity, the magnetocaloric effect and the magnetic refrigeration capacity are not very high, and achieve the effect of strong refrigeration capacity.

Active Publication Date: 2015-12-30
UNIV OF SCI & TECH BEIJING
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the magnetocaloric effect and magnetic refrigeration capacity of these materials are still not very high, and the magnetic refrigeration materials with a first-order magnetic phase transition (such as ErCo 2 ) is usually accompanied by obvious thermal hysteresis and magnetic hysteresis, which leads to the decline of the effective magnetic refrigeration capacity of the magnetic refrigeration material during the cycle

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
  • Preparation method of rare earth-nickel-gallium material with colossal magnetic refrigeration capability
  • Preparation method of rare earth-nickel-gallium material with colossal magnetic refrigeration capability
  • Preparation method of rare earth-nickel-gallium material with colossal magnetic refrigeration capability

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0034] This embodiment is used to illustrate the magnetic refrigeration material provided by the present invention and its preparation method.

[0035] 1. Preparation method:

[0036] 1) Weigh the material according to the atomic ratio in the HoNiGa chemical formula, mix the commercially available rare earth metal Ho with a purity higher than 99.9% with Ni and Ga raw materials, wherein Ho is added in excess of 2% of the atomic percentage in the chemical formula HoNiGa, for Compensate for the volatilization of Ho during the preparation process;

[0037] 2) Put the raw materials prepared in step 1) into the electric arc furnace to vacuumize, when the vacuum degree reaches 3×10 -3 Pa, after cleaning twice with pure argon, melt under the protection of pure argon at 1 atmosphere, the melting time is 3 minutes, and the melting temperature is 1400-1500°C;

[0038] 3) Cool the as-cast alloy in a copper crucible, wrap the as-cast alloy with molybdenum foil, and seal it in a vacuum of...

Embodiment 2

[0054] This embodiment is used to illustrate the magnetic refrigeration material provided by the present invention and its preparation method.

[0055] 1. Preparation method:

[0056] 1) Weighing according to the atomic ratio in the ErNiGa chemical formula, mixing commercially available rare earth metal Er with a purity higher than 99.9% with Ni and Ga raw materials, wherein Er is added in excess of 2% of the atomic percentage in the chemical formula ErNiGa;

[0057] 2) Put the raw materials prepared in step 1) into the electric arc furnace to vacuumize, when the vacuum degree reaches 3×10 -3 Pa, after cleaning twice with pure argon, melt under the protection of pure argon at 1 atmosphere, the melting time is 3 minutes, and the melting temperature is 1400-1500°C;

[0058] 3) Cool the as-cast alloy in a copper crucible, wrap the as-cast alloy with molybdenum foil, and seal it in a vacuum of 5×10 -3 In the quartz tube of Pa, it was annealed at 950°C for 25 days, taken out and ...

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

PropertyMeasurementUnit
Refrigeration capacityaaaaaaaaaa
Magnetic entropy changeaaaaaaaaaa
Login to view more

Abstract

The invention provides a rare earth-nickel-gallium refrigerating material with a colossal magnetothermal effect and a preparation method of rare earth-nickel-gallium refrigerating material. The material is a compound of which the general formula is RNiGa; and R is one of Tb, Dy, Ho and Er elements optionally or a combination of Tb, Dy, Ho and Er elements optionally. The preparation method of the material comprises the following steps of combining and configuring raw materials according to a specific proportion; placing the configured raw materials in a smelting furnace; performing vacuumizing and cleaning the raw materials with argon; smelting under the protection of the argon; performing vacuum annealing treatment on the smelted materials; and taking out the materials from the smelting furnace and cooling down the materials quickly. The rare earth-nickel-gallium material is provided by the invention, and particularly, because HoNiGa has antiferromagnetic-ferromagnetic metamagnetic transition induced by a magnetic field, the HoNiGa has large magnetic entropy change when the temperature of the HoNiGa is close to a phase-transition temperature thereof. The rare earth-nickel-gallium refrigerating material is wide in working temperature zone, large in magnetic refrigeration capability and good in thermal and magnetic reversibility, and is a perfect low-temperature magnetic refrigerating material.

Description

technical field [0001] The invention relates to magnetic materials, in particular to a rare earth-nickel-gallium material with large magnetic refrigeration capacity, its preparation method and its application in magnetic refrigeration technology. Background technique [0002] In recent years, with the increasing shortage of modern energy and the increasing awareness of environmental protection, magnetic refrigeration technology has attracted more and more attention. Magnetic refrigeration refers to a new type of green and environmentally friendly refrigeration technology that uses magnetic materials as refrigerants. When the arrangement is ordered, the magnetic material will release heat during isothermal magnetization, and the magnetic entropy will decrease at the same time; and when the magnetic field is removed, the atomic magnetic moments will return to the previous random state, and the magnetic material will absorb heat while the magnetic entropy will increase. Compar...

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
IPC IPC(8): C22C1/02C22F1/02C22F1/16
Inventor 张虎李亚伟陶坤吴美玲龙毅
Owner UNIV OF SCI & TECH BEIJING
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