Patent · US Expired

Rare earth magnet and method for making same

US6527874B2 · kind B2 · utility

19Cited by
13References
8Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 10, 2001
Grant dateMar 4, 2003
Priority date
Expiry dateJul 10, 2021

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01F1/058
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A rapidly solidified alloy is produced by quenching and solidifying a melt of an alloy having a general formula represented by (Fe1-mTm)100-x-y-zQxRyMz where T denotes at least one kind of element selected from the group consisting of Co and Ni, Q denotes at least one kind of element selected from the group consisting of B and C, R denotes at least one kind of rare earth element, and M denotes at least one kind of element selected from the group consisting of Nb and Mo, and the mole fractions x, y, z, and m respectively satisfy 2&lE;x&lE;28 (atom %), 8&lE;y&lE;30 (atom %), 0.1 &lE;z<1.0 (atom %), and 0&lE;m&lE;0.5 (atom %). The rapidly solidified alloy is then pulverized and sintered to manufacture a rare earth permanent magnet. The cooling rate is controlled to be in the range of 102 K/sec to 104 K/sec, so that the alloy structure is uniformly fine and the added element M is uniformly dispersed.

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