Patent ID: 9548149
Date: 2017-01-17
CPC Classifications: H01F

Claim:
1. A rare earth based magnet, comprising, R wherein said R in the section of the main-phase crystal grains, the longest line segment in the section is taken as the long axis of the grains, a line segment in the grain section that passes through the center of the grains and is perpendicular to the long axis is taken as the short axis; the lines which orthogonally divide the long axis and short axis into ¾ inward and ¼ outward are determined, and an ellipse tangent to the four lines is drawn with its long axis and short axis parallel to the long axis and short axis of the grains respectively; when the ellipse is regarded as the boundary, the grains are divided into the interior of the crystal grains which is the interior of the ellipse and the periphery of the crystal grains which is the exterior of the ellipse; the fine products are formed such that the number density in the interior of the crystal grains is larger than that in the periphery of the crystal grains, when the number density of said fine products in said interior of the crystal grains is taken as A1 and the number density of said fine products in said periphery of the crystal grains is taken as A2, A1/A2≧3.0, and wherein, said two-grain boundary phases have a width of 5 nm or more and 200 nm or less.