Method for increasing sintering Nd-Fe-B coercive force by adding nano-oxide in crystal boundary phase

A nano-oxide, neodymium-iron-boron technology, applied in the direction of magnetic objects, inductors/transformers/magnets, magnetic materials, etc., can solve the problems of magnet remanence and adverse effects of magnetic energy product, and achieve high coercive force, magnet coercive force, etc. High coercive force, not easy to oxidize

Inactive Publication Date: 2005-10-26
ZHEJIANG UNIV
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Element addition and substitution are common methods to improve the coercive force. Studies have found that elements such as Dy, Al, Nb, Ga, Tb, W, and Mo can

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] 1) Prepare the main phase alloy and the grain boundary phase alloy separately. The main phase alloy adopts the quick-setting sheet technology, the surface speed of the copper roller is 1.2m / s, and the composition is Nd 13.12 Fe 80.31 B 5.73 (Dy 0.32 Al 0.24 Nb 0.28 )(at%), the grain boundary phase alloy is prepared into a rapid quenching zone with a rapid quenching speed of 20m / s, and the composition is Nd 17.2 Fe 75.04 B 6.38 Dy 0.64 Ga 0.2 Cu 0.54 (at%).

[0031] 2) Powder the main phase alloy and the grain boundary phase alloy respectively. The primary crushing is carried out by a jaw crusher, the secondary crushing is carried out by a secondary crusher, and then the powder with an average particle diameter of 3 μm is made by jet milling under the protection of nitrogen.

[0032] 3) Adding 10% by weight of dispersed nano-Al to the grain boundary phase alloy powder 2 o 3 The powder (with an average particle diameter of 30nm) and 3% of antioxidant polyeth...

Embodiment 2

[0042] 1) Prepare the main phase alloy and the grain boundary phase alloy separately. The main phase alloy adopts the quick-setting sheet technology, the surface line speed of the copper roller is 2.0m / s, and the composition is Nd 14.2 Fe 78.13 B 5.81 (Tb 0.21 Al 0.24 co 1.12 Nb 0.28 )(at%), the grain boundary phase alloy is prepared into a rapid quenching zone with a rapid quenching speed of 18m / s, and the composition is

[0043] Nd 16.7 Fe 76.27 B 6.31 (Dy 0.84 Ga 0.2 Cu 0.32 )(at%).

[0044] 2) Powder the main phase alloy and the grain boundary phase alloy respectively. Direct crushing by hydrogen explosion method, saturated hydrogen absorption at room temperature, and then dehydrogenation at 500 ° C for 8 hours to make hydrogen explosion powder, and then under nitrogen protection to make powder with an average particle diameter of 3.3 μm by jet milling.

[0045] 3) Adding 10% by weight of dispersed nano-SiO to the grain boundary phase alloy powder 2 The powd...

Embodiment 3

[0055] 1) Prepare the main phase alloy and the grain boundary phase alloy separately. The main phase alloy adopts the quick-setting sheet technology, the surface speed of the copper roller is 2.2m / s, and the composition is Nd 11.06 Fe 82.25 B 5.9 Dy 0.79 (at%), using rapid quenching technology, the grain boundary phase alloy Nd 27.83 Fe 56.2 B 6.68 Dy 2.47 co 6.82 (at%) is prepared as a quenching belt, and the quenching speed is 18m / s.

[0056] 2) Powder the main phase alloy and the grain boundary phase alloy respectively. The primary crushing is carried out by a jaw crusher, the secondary crushing is carried out by a secondary crusher, and then the powder with an average particle diameter of 4.0 μm is made by jet milling under the protection of nitrogen.

[0057] 3) In the grain boundary phase alloy powder, add nano-SiO which accounts for 5% of its weight through dispersion treatment 2 Powder (average particle diameter is 10nm), 5% nano ZrO 2 The powder (with an av...

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Abstract

This invention discloses a method for increasing sintered Nd FeB coercive force by adding nm oxide in grain-boundary phase including the following steps: 1,applying casting technology to produce NdFeB ingot alloy or applying rapid hardening film technology to produce NdFeB rapid hardening film of with host phase alloy, applying casting technology to produce ingot alloy or rapid hardening film technology to get rapid hardening film or rapid quench technology to manufacture a rapid quench strip with the grain boundary phase alloy, 2, processing powder with the two alloys, 3, adding a nm oxide to the grain boundary phase alloy powder, 4, pressing the mixed powder into formation, 5, producing sintered magnetic body in a vacuum sintering oven.

Description

technical field [0001] The invention relates to a method for increasing the coercive force of sintered NdFeB by adding nanometer oxides in the grain boundary phase. Background technique [0002] NdFeB rare earth permanent magnet materials were first manufactured by Sagawa and others from Sumitomo Special Metals Company in Japan in 1983. Rare earth NdFeB permanent magnets are the most magnetic permanent magnets in contemporary times. They not only have excellent characteristics such as high magnetic energy product and high cost performance, but also are easy to process into various sizes. They have been widely used in aviation, aerospace, microwave communication technology, electronic , electroacoustic, electromechanical, computing technology, automation technology, automobile industry, petrochemical industry, magnetic separation technology, instrumentation, magnetic medical technology and other devices and equipment that require permanent magnetic fields, especially suitable...

Claims

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Application Information

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IPC IPC(8): H01F1/08
Inventor 严密于濂清罗伟
Owner ZHEJIANG UNIV
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