Magnetic powder and bonded magnet
AssigneeSeiko Epson Corporation
InventorsAkira Arai, Hiroshi Kato
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Abstract
Disclosed herein is a magnetic powder which can provide a bonded magnet having high mechanical strength and excellent magnetic properties. The magnetic powder has an alloy composition containing a rare-earth element and a transition metal, wherein the magnetic powder includes particles each of which is formed with a number of ridges or recesses on at least a part of a surface thereof. In this magnetic powder, it is preferable that when the mean particle size of the magnetic powder is defined by aμm, the average length of the ridges or recesses is equal to or greater than a/40 μm. Further, preferably, the ridges or recesses are arranged in roughly parallel with each other so as to have an average pitch of 0.5-100 μm.
Claims17
A magnetic powder comprising:
- an alloy composition including a rare-earth element and a transition metal, the alloy composition being selected from the group consisting of Sm—Co based alloys, R—TM—B based alloys, Sm—Fe—N alloys, alloys having a composite structure in which a soft magnetic phase and a hard magnetic phase are adjacent one another, and mixtures of the alloys thereof,
- wherein R of the R—TM—B based alloy is at least one rare-earth element selected from the group consisting of La, Ce, Pr, Pm, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and misch metal;
- and
- wherein the magnetic powder includes particles each of which is formed with a number of ridges or recesses on at least a part of the surface thereof;
- and
- the ridges or recesses are arranged parallel with each other to have an average pitch of 1.0-35.3 μm.
A magnetic powder comprising:
- an alloy composition including a rare earth element and a transition metal, the alloy composition being selected from the group consisting of Sm—Co based alloys, R—TM—B based alloys;
- Sm—Fe—N alloys, and mixtures of the alloys thereof,
- wherein R of the R—TM—B based alloy is at least one rare-earth element selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and misch metal;
- and
- wherein the magnetic powder includes particles each of which is formed with a number of ridges or recesses on at least a part of a surface thereof and arranged parallel with each other to have an average pitch of 1.0-35.3 μm;
- the magnetic powder is composed of a composite structure having a soft magnetic phase and a hard magnetic;
- and
- the soft magnetic phase and hard magnetic phase have an average crystal grain size of 2-100 nm.
Dependencies are inferred from the claim text.