Oxide magnetic material, ferrite particles, bonded magnet, sintered magnet, process for producing the same, and magnetic recording medium
US6402980B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 19, 1999 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | May 19, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/113
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides an oxide magnetic material, which includes a primary phase of a hexagonal ferrite containing metallic elements Ca, R, Fe and M, where M represents at least one element selected from the group including Co, Ni and Zn, and R represents at least one element selected from the group including Bi and rare earth elements including Y, with La being essentially included in R; wherein the proportions of the metallic elements Ca, R, Fe and M with respect to the total amount of the metallic elements are from 1 to 13 atomic % for Ca, from 0.05 to 10 atomic % for R, from 80 to 95 atomic % for Fe, and from 1 to 7 atomic % for M. The present invention also provides ferrite particles, a bonded magnet, a sintered magnet, a process for producing them, and a magnetic recording medium, which contain the oxide magnetic material.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.