The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 12, 2021
Filed:
Feb. 25, 2019
Santoku Corporation, Hyogo, JP;
Takayuki Shimizu, Yachiyo, JP;
SANTOKU CORPORATION, Hyogo, JP;
Abstract
Provided is an R-T-B-based magnet material alloy including an RTB phase which is a principal phase and R-rich phases which are phases enriched with the R, wherein the principal phase has primary dendrite arms and secondary dendrite arms diverging from the primary dendrite arms, and regions where the secondary dendrite arms have been formed constitute a volume fraction of 2 to 60% of the alloy, whereby excellent coercive force can be ensured in R-T-B-based sintered magnets even when the amount of heavy rare earth elements added to the alloy is reduced. The inter-R-rich phase spacing is preferably at most 3.0 μm, and the volume fraction of chill crystals is preferably at most 1%. Furthermore, the secondary dendrite arm spacing is preferably 0.5 to 2.0 μm, and the ellipsoid aspect ratio of R-rich phase is preferably at most 0.5.