R-T-B based permanent magnet
AssigneeTDK Corporation
InventorsHikaru Kudo, Atsushi Koda, Takahiro Suwa
Life of this patent
Estimating the term…
Abstract
An R-T-B-based permanent magnet including: R (rare earth element); T (Fe and Co); B (boron); and one or more selected from Al, Cu, Ga, and Zr. R includes Ce. The total R content is 31.3-34.0 mass % (inclusive), the Co content is 1.85-3.00 mass % (inclusive), the B content is 0.80-0.90 mass % (inclusive), the Al content is 0.03-0.90 mass % (inclusive), the Cu content is 0-0.25 mass % (inclusive), the Ga content is 0-0.10 mass % (inclusive), the Zr content is 0-0.60 mass % (inclusive), and the Fe content is substantially the remainder. The Ce content relative to R is 15-25 mass % (inclusive).
Claims16
An R-T-B based permanent magnet comprising R, T, B, Al, and Zr;
- wherein
- R is a rare earth element and at least includes Ce,
- a total amount of R is within a range of 31.3 mass % or more and 34.0 mass % or less,
- T is Fe and Co,
- an amount of Co is within a range of 1.85 mass % or more and 2.80 mass % or less,
- an amount of B is within a range of 0.80 mass % or more and 0.90 mass % or less,
- an amount of Al is within a range of 0.03 mass % or more and 0.90 mass % or less,
- an amount of Cu is within a range of 0 mass % or more and 0.25 mass % or less,
- an amount of Ga is within a range of 0 mass % or more and 0.10 mass % or less,
- an amount of Zr is within a range of 0.10 mass % or more and 0.60 mass % or less,
- an amount of Fe is a substantial balance, and
- an amount of Ce to the total amount of R is within a range of 0.15 or more and 0.25 or less.
Dependencies are inferred from the claim text.