Ferrite magnet
AssigneeTDK Corporation
InventorsJunnichi Nagaoka, Hitoshi Taguchi
Life of this patent
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Abstract
This ferrite magnet has a ferrite phase having a magnetoplumbite structure, and an orthoferrite phase, and is characterized in that the composition ratios of the total of each metal element A, R, Fe and Me is represented by expression (1) A1-xRx(Fe12-yMey)z, (in expression (1), A is at least one element selected from Sr, Ba, Ca and Pb; R is at least one element selected from the rare-earth elements (including Y) and Bi, and includes at least La, and Me is Co, or Co and Zn) and in that the content (m) of the orthoferrite phase is 0<m<28.0 in mol %. The invention makes it possible to achieve a ferrite magnet with increased Br.
Claims2
A ferrite magnet comprising a ferrite phase having a magnetoplumbite structure and an orthoferrite phase, wherein
- a constitutional proportion of metal elements of A, R, Fe, and Me is represented by a formula (1) of A1-xRx(Fe12-yMey)z, where A is at least one element selected from Sr, Ba, Ca, and Pb, R is at least one element selected from rare earth elements (including Y) and Bi and R at least includes La, and Me is Co or Co and Zn,
- x, y, and z of the formula (1) satisfy the following formulae (2), (3), (4), and (5):
- 0.71≤x≤0.84 (2);
- 0.30≤y≤0.60 (3);
- 0.80≤z<1.10 (4);
- 1.60<x/yz<4.00 (5), and
- 0<m<28.0 is satisfied, where m is an orthoferrite-phase content by mol %.
Dependencies are inferred from the claim text.