Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for preparing large-size sintered samarium cobalt permanent magnet

A permanent magnet and large-size technology, applied in the direction of magnetic objects, magnetic materials, inorganic materials, etc., can solve problems such as connection process and strength limitations, low pass rate, degumming, etc., to achieve no abnormal appearance of the magnet, excellent magnetic properties, The effect of simple process

Active Publication Date: 2017-05-31
HUNAN AEROSPACE MAGNET & MAGNETO
View PDF6 Cites 16 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the density uniformity of the large green body pressed in this way is poor, and it is difficult to take the green body. After sintering, the size of the green body is greatly deformed, and there are internal cracks, and the qualified rate is very low.
A method for preparing a large-size bonded permanent magnet disclosed in CN104361989A, but because it has a huge difference with the sintered permanent magnet in the formulation components and preparation process, it is not comparable and referential
However, this method will be limited in terms of connection process and strength. The glue will age with time, which will affect the service life of the magnet assembly workpiece, and the working temperature should generally not exceed 200 ° C, otherwise it will be degummed
CN106158200A discloses a method for manufacturing a radially oriented large-size samarium-cobalt cylindrical magnet. It mentions the method of using glue between magnets and marking lines to locate the magnetic poles, but does not mention the working temperature requirements of this type of magnet. Similarly, if the working environment If the temperature exceeds 200°C, it is obviously not suitable for
However, in a vibration environment, long-term fatigue loosening will also limit the service life of the magnet assembly workpiece, and at the same time, the mechanical connection is more likely to cause the magnet to break
[0007] Therefore, the effects of obtaining super-large-sized sintered samarium-cobalt magnets through the above three methods are not ideal, and it is urgent to find a reliable method for preparing super-large-sized sintered samarium-cobalt magnets

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
  • Method for preparing large-size sintered samarium cobalt permanent magnet
  • Method for preparing large-size sintered samarium cobalt permanent magnet
  • Method for preparing large-size sintered samarium cobalt permanent magnet

Examples

Experimental program
Comparison scheme
Effect test

reference example 1

[0049] The preparation method of samarium-cobalt alloy ingot: by weight, 25.5 parts of Sm, 52 parts of Co, 12.5 parts of Fe, 7 parts of Cu and 3 parts of Zr are placed in a vacuum intermediate frequency induction furnace, and the vacuum is evacuated to a vacuum degree of 0.08Pa. Then fill the furnace with argon until the pressure in the furnace is -0.05MPa, melt at 1500°C for 15 minutes, then heat-preserve and refine at 1440°C for 5 minutes, and finally pour it into a cooling mold for rapid cooling and casting.

Embodiment 1

[0051] (1) The samarium-cobalt alloy ingot obtained in Reference Example 1 is roughly crushed into coarse particles with an average particle size of 300 μm by a jaw crusher and a secondary crusher, and pulverized by a jet mill into jet mill magnetic powder with an average particle size of 3.8 μm. Add 120# aviation gasoline equivalent to 3% of its mass in the magnetic powder, and mix with a double-cone mixer for 1 hour to obtain magnetic powder;

[0052] (2) Two parts of 1530g of the magnetic powder mixed in step (1) are respectively placed in a magnetic field of 1.6T and a pressure of 4MPa, orientated and press-molded into a size specification of 110 (front-back direction)×65 (pressing direction)× 58 (Magnetization direction) mm, density 3.69g / cm 3 The shrinkage rate of a single green body in the pressing direction is designed to be 1.313, that is, 65 (dimensions in the pressing direction of the green body) × 2 / 99 (dimensions in the direction of blank pressing) = 1.313, and th...

Embodiment 2

[0057] (1) Same as step (1) of Example 1;

[0058] (2) Two parts of 1640g of the magnetic powder mixed in step (1) are placed in a magnetic field of 2.0T, respectively, under a pressure of 6MPa, and oriented and pressed into a size specification of 115 (front and rear direction) × 66 (pressing direction) × 60 (Magnetization direction) mm, density 3.60g / cm 3 The shrinkage rate of a single green body in the pressing direction is designed to be 1.320, that is, 66 (dimensions in the pressing direction of the green body) / 50 (dimensions in the direction of blank pressing) = 1.320, the shrinkage rate in the front and rear directions is 1.349, and the shrinkage rate in the direction of magnetization The corresponding value is 1.282, and two identical green bodies are obtained;

[0059] (3) Arrange the two green bodies obtained in step (2) along the front and back directions, and arrange the magnetization direction between the two green bodies crosswise, and arrange the upper indenter...

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
The average particle sizeaaaaaaaaaa
The average particle sizeaaaaaaaaaa
Login to View More

Abstract

A method for preparing a large-size sintered samarium cobalt permanent magnet includes the following steps that firstly, a samarium cobalt alloy ingot is smashed, milled and mixed to obtain magnetic powder; secondly, oriented-pressing and forming are conducted in a magnetic field to obtain blanks; thirdly, two or more blanks are spliced together and tightly wrapped by fresh-keeping films, vacuum packaging is conducted, cold isostatic pressing is conducted, and a formed blank is obtained; fourthly, the formed blank is subjected to vacuum pre-sintering, inert gas is introduced for sintering, solid solution is conducted, air cooling is conducted to normal temperature, and a sintered blank is obtained; fifthly, the sintered blank is subjected to aging treatment, cooling and heat preservation are conducted, air cooling is conducted to normal temperature, and the large-size sintered samarium cobalt permanent magnet is obtained through machining. The ultra-large sintered samarium cobalt permanent magnet with the unilateral size larger than 130 mm can be prepared through the method, is good in magnetic property, and can reach the XGS30H trademark magnet standard, the product yield reaches 94% or above, the magnetic property is not changed after temperature-resistant and fatigue testing, and the appearance is normal. The process is simple, large-scale production can be achieved, and the cost is low.

Description

technical field [0001] The invention relates to a method for preparing a permanent magnet, in particular to a method for preparing a large-scale sintered samarium-cobalt permanent magnet. Background technique [0002] Sintered samarium cobalt permanent magnet material is a new type of functional material developed since the 1960s. It has high magnetic energy product, high coercive force, extremely low temperature coefficient, high temperature resistance (above 350 ° C), corrosion resistance, oxidation resistance, etc. With excellent characteristics, it is widely used in motors, instruments, sensors, detectors, engines, radars and other high-tech and military fields. The method of preparing samarium-cobalt permanent magnet materials in industrial production is mainly powder metallurgy. The general production process is: batching → smelting → powder making → molding → sintering → tempering → magnetic detection → post-processing → surface treatment → inspection → finished produ...

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): H01F1/057H01F1/08B22F3/02B22F3/04B22F3/10
CPCB22F3/02B22F3/04B22F3/101H01F1/0551H01F1/0556H01F1/0557
Inventor 王涛谭春林罗明
Owner HUNAN AEROSPACE MAGNET & MAGNETO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com