Unlock instant, AI-driven research and patent intelligence for your innovation.

ndfeb sintered magnet

A sintered magnet, total volume technology, applied in the direction of magnetic objects, magnetic materials, inorganic materials, etc., can solve the problem of slow diffusion

Active Publication Date: 2016-07-06
DAIDO STEEL CO LTD
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In contrast, since the main phase particles are still solid, the diffusion rate from the grain boundary into the main phase particles is slow

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
  • ndfeb sintered magnet
  • ndfeb sintered magnet
  • ndfeb sintered magnet

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0044] For the method of manufacturing the NdFeB system sintered magnets of the present embodiment and comparative example, use figure 1 and figure 2 The flow chart is described.

[0045] Such as figure 1 As shown, the manufacturing method of the NdFeB-based sintered magnet of this embodiment includes the following steps: Hydrogen crushing step (step A1): roughening the NdFeB-based alloy by storing hydrogen in the NdFeB-based alloy prepared in advance by strip casting (StripCasting) method. Crushing; fine pulverization process (step A2): Mix 0.05 to 0.1 wt% of a lubricant such as methyl octanoate in the NdFeB-based alloy that has not been heated for dehydrogenation after hydrogen crushing in the hydrogen crushing process, and use a jet mill device Finely pulverize in a nitrogen gas flow so that the median value (D50) of the particle size distribution measured by the laser diffraction method is 3.2 μm or less; filling process (step A3): mix 0.05 to 0.15 wt% in the finely p...

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
particle sizeaaaaaaaaaa
Login to View More

Abstract

The present invention provides a NdFeB-based sintered magnet manufactured by a grain boundary diffusion method, which has high coercive force and squareness ratio, and has little decrease in maximum energy product. The NdFeB-based sintered magnet of the present invention is characterized in that Dy and / or Tb (hereinafter, "Dy and / or Tb" will be referred to as "RH") adhering to the surface of the base material is diffused to the The NdFeB-based sintered magnet at the grain boundary inside the base material produced by orienting and sintering the powder of the NdFeB-based alloy, the RH concentration Cs (wt %) and the RH concentration Cd3 (wt%) in the grain boundary at a depth of 3mm from the attachment surface, Cs-Cd3, is 20wt% or less.

Description

technical field [0001] The present invention relates to a NdFeB-based sintered magnet produced by grain boundary diffusion treatment. Background technique [0002] NdFeB-based sintered magnets were discovered by Sagawa (one of the inventors) in 1982. It has characteristics significantly surpassing those of permanent magnets at that time. It can be composed of Nd (a kind of rare earth), iron and boron. Advantages of cheap raw materials to manufacture. Therefore, NdFeB-based sintered magnets are used in driving motors for hybrid vehicles or electric vehicles, motors for electrically-assisted vehicles, industrial motors, voice coil motors such as hard disks, high-end speakers, earphones, and permanent magnet magnetic resonance diagnostic devices. and other products. NdFeB-based sintered magnets used in these applications are required to have high coercive force H cJ , High maximum energy product (BH) max and high rectangular ratio sq. The squareness ratio SQ here is define...

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 Patents(China)
IPC IPC(8): H01F1/08B22F1/00B22F3/00C22C33/02H01F1/057H01F41/02
CPCC22C2202/02C22C33/02H01F41/0293C22C38/005H01F1/0577H01F1/08H01F1/057H01F41/02B22F1/05B22F3/10
Inventor 佐川真人沟口彻彦
Owner DAIDO STEEL CO LTD