Beijing Zhong Ke San Huan Hi-tech Co., Ltd.

Sanvac (beijing) Magnetics Co., Ltd.

Haojie Wang

Guoan Chen

E Niu

Yugang Zhao

Wei Zhu

Boping Hu

Xiaolei Rao

Bin Fang

Yeqing He

Zhi'an Chen

Fenghua Chen

Jin Zhang

Zhan Wang

Xuanzhang Ye

Fei Du

A NdFeB rare earth magnet includes a main phase and a grain boundary phase including a white grain boundary phase and a gray grain boundary phase. In a microstructure observation area of the rare earth magnet, an area of the white grain accounts for 1˜3% of a total area of the microstructure observation area, and an area of the gray grain boundary phase accounts for 2˜10% of the total area of the microstructure observation area.

Rare earth magnet and preparation method thereof

A composite coating layer for coating a NdFeB rare earth magnet includes a first coating layer and a second coating layer formed over a surface of the first coating layer. The first coating layer includes a Nd coating layer, a Pr coating layer, or an alloy coating layer including two or more of Nd, Pr, and Cu. The second coating layer includes a Tb coating layer.

Coating machine and coating method

Disclosed herein is a method for manufacturing an R-T-B permanent magnet and the magnet made with the method. The method may include preparation of strip pieces by melting and casting, preparing coarse powder by hydrogen decrepitation of the strip pieces; milling the powder into fine powder; pressing the fine powder is pressed to form a compact, pre-sintering the compact in vacuum or inert gas, machining the pre-sintered block to a desired shape; and dispersing the heavy rare earth compound powder into an organic solvent to prepare a slurry and a second sintering step.

Method for preparing an R-T-B permanent magnet

The present invention discloses a rare earth permanent magnet and a method for preparing same. The material of the rare earth permanent magnet has a heavy rare earth element volume diffusion phenomenon at a depth of 5 &#x3bc;m to 100 &#x3bc;m from the surface of the magnet to the interior of the magnet along the magnetic field orientation direction, thereby forming a volume diffusion layer region; the volume diffusion layer region is divided into magnet units having a volume of 10*100*5 &#x3bc;m, and the concentration difference of the heavy rare earth elements of the magnet units at different positions in the volume diffusion layer is below 0.5 at %. The present invention provides a sintered NdFeB magnet of high intrinsic coercive force Hcj on the premise of not influencing the remanence Br and the maximum magnetic energy product (BH)max of products. In the method for preparing the rare earth permanent magnet, microwave heat treatment is performed on a blank magnet coated with heavy rare earth source slurry in a vacuum condition. This method can effectively improve the heating efficiency, reduce the heat treatment time, lower the energy consumption, and reduce the production cost of the magnet.

Rare earth permanent magnet and method for preparing same

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Beijing, China

Haojie Wang