Permanent magnet and rotary electrical machine
AssigneeKabushiki Kaisha Toshiba
InventorsYosuke Horiuchi, Shinya Sakurada, Naoyuki Sanada
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Abstract
A high-performance permanent magnet is provided. A permanent magnet expressed by a composition formula: RpFeqMrCutCo100-p-q-r-t-. The magnet comprises a metal structure including a cell phase having a Th2Zn17 crystal phase, and a Cu-rich phase provided to divide the cell phase and having a Cu concentration higher than that of the Th2Zn17 crystal phase. An Fe concentration of the Th2Zn17 crystal phase is not less than 30 atomic % nor more than 45 atomic %. An average length of the Cu-rich phase is not less than 30 nm nor more than 250 nm.
Claims7
A permanent magnet expressed by a composition formula:
- RpFeqMrCutCo100-p-q-r-t
- where R is at least one element selected from the group consisting of rare earth elements, M is at least one element selected from the group consisting of Zr, Ti, and Hf, p is a number satisfying 10.5 p 12.4 atomic %, q is a number satisfying 28 q 40 atomic %, r is a number satisfying 0.88 r 4.3 atomic %, and t is a number satisfying 3.5 t 13.5 atomic %,
- the magnet comprising:
- a metal structure including a cell phase having a Th2Zn17 crystal phase, and a Cu-rich phase provided to divide the cell phase and having a Cu concentration higher than that of the Th2Zn17 crystal phase,
- wherein an Fe concentration of the Th2Zn17 crystal phase is not less than 30 atomic % nor more than 45 atomic %, and
- an average length of the Cu-rich phases is not less than 30 nm nor more than 250 nm.
Dependencies are inferred from the claim text.