Rare-earth permanent magnetic powder, bonded magnet, and device comprising the same

US9245674B2 · kind B2 · utility

Assignee

• GRIREM ADVANCED MATERIALS CO., LTD. · CN

Inventors

• Hongwei Li · Burnaby, CA
• Dunbo Yu · Beijing, CN
• Yang Luo · Amherst, US
• Kuoshe Li · Beijing, CN
• Shipeng Li · Princeton, US
• Min Wang · Santa Clara, US
• Yongqiang Yuan · Beijing, CN

Key dates

• Filing date: Mar 28, 2011
• Grant date: Jan 26, 2016
• Expiry date: Mar 28, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2982
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A rare-earth permanent magnetic powder, a bonded magnet, and a device comprising the bonded magnet are provided. The rare-earth permanent magnetic powder is mainly composed of 7-12 at % of Sm, 0.1-1.5 at % of M, 10-15 at % of N, 0.1-1.5 at % of Si, and Fe as the balance, wherein M is at least one element selected from the group of Be, Cr, Al, Ti, Ga, Nb, Zr, Ta, Mo, and V, and the main phase of the rare-earth permanent magnetic powder is of TbCu7 structure. Element Si is added into the rare-earth permanent magnetic powder for increasing the ability of SmFe alloy to from amorphous structure, and for increasing the wettability of the alloy liquid together with the addition of element M in a certain content, which enables the alloy liquid prone to be injected out of a melting device. The average diameter of the rare-earth permanent magnetic powder is in the range of 10-100 μm, and the rare-earth permanent magnetic powder is composed of nanometer crystals with average grain size of 10-120 nm or amorphous structure.