Patent · US Expired

Rare earth-iron series permanent magnets and method of preparation

US6136099A · kind A · utility

2Cited by
16References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 19, 1993
Grant dateOct 24, 2000
Priority date
Expiry dateMar 19, 2013

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D6/00
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A rare earth-iron series magnet formed from an alloy ingot using a one-step hot working process is provided. The alloy ingot includes between about 8 and 30 atomic percent of at least one rare earth element, between about 2 and 28 atomic percent of boron, less than about 50 atomic percent of cobalt, less than about 15 atomic percent of aluminum and the balance of iron and other impurities that are inevitably included during the preparation process. The alloy is cast to obtain a cast ingot and the hot working is performed on the cast ingot at a temperature of greater than about 500.degree. C. in order to make the crystal grains of the ingot fine and to align the axis of the grains in a desired direction.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.