摘要:
There is provided a rare earth magnet with excellent Br and HcJ values. The rare earth magnet according to a preferred embodiment of the invention is characterized by being composed mainly of R (where R is at least one element selected from among rare earth elements including Y), B, Al, Cu, Zr, Co, O, C and Fe, wherein the content of each element is R: 25-34 wt %, B: 0.85-0.98 wt %, Al: 0.03-0.3 wt %, Cu: 0.01-0.15 wt %, Zr: 0.03-0.25 wt %, Co: ≦3 wt % (but not 0 wt %), O: ≦0.2 wt %, C: 0.03-0.15 wt % and Fe: remainder.
摘要:
There is provided a rare earth magnet with excellent Br and HcJ values. The rare earth magnet according to a preferred embodiment of the invention is characterized by being composed mainly of R (where R is at least one element selected from among rare earth elements including Y), B, Al, Cu, Zr, Co, O, C and Fe, wherein the content of each element is R: 25-34 wt %, B: 0.85-0.98 wt %, Al: 0.03-0.3 wt %, Cu: 0.01-0.15 wt %, Zr: 0.03-0.25 wt %, Co: ≦3 wt % (but not 0 wt %), O: ≦0.2 wt %, C: 0.03-0.15 wt % and Fe: remainder.
摘要:
The invention provides a process for producing a magnet that not only allows satisfactory Br and HcJ values to be achieved but can also yield a magnet with a sufficiently large squareness ratio. The process for producing a magnet according to the invention is characterized by comprising a first step in which a heavy rare earth compound containing a heavy rare earth element is adhered onto a rare earth magnet sintered compact, and a second step in which the heavy rare earth compound-adhered sintered compact is subjected to heat treatment. The heavy rare earth compound is a hydride of the heavy rare earth element.
摘要:
Provided is a rare earth sintered magnet 10 comprising a group of main phase grains 2 each composed of an R-T-B-based rare earth magnet comprising a core 4 and a shell 6 covering the core 4, wherein a thickness of the shell 6 is 500 nm or less, R includes a light rare earth element and a heavy rare earth element, and a Zr compound 8 is present in a grain boundary phase 7 of the group of main phase grains 2 and/or the shell 6. Also provided are a motor comprising the rare earth sintered magnet 10 and an automobile comprising the motor.
摘要:
The present invention provides a sintered magnet having superior residual magnetic flux density and coercive force. The sintered magnet of the present invention comprises a group of R-T-B based rare earth magnet crystal particles 2 having a core 4 and a shell 6 covering the core 4, the mass ratio of a heavy rare earth element in the shell 6 is higher than the mass ratio of a heavy rare earth element in the core 4, and the thickest part of the shell 6 in the crystal particles 2 faces a grain boundary triple junction 1. A lattice defect 3 is formed between the core 4 and the shell 6.
摘要:
In the rare earth sintered magnet, the ratio of R2 to the sum of R1 and R2 that are contained in crystal grain boundaries surrounding the crystal grains in the rare earth sintered magnet body is higher than the ratio of R2 to the sum of R1 and R2 in the crystal grains, and the concentration of R2 increases from the central portion of the rare earth sintered magnet body toward the surface of the rare earth sintered magnet body. In addition, the degree of unevenness in residual magnetic flux density on the surface of the rare earth sintered magnet body is smaller than 3.0%.
摘要:
In the rare earth sintered magnet, the ratio of R2 to the sum of R1 and R2 that are contained in crystal grain boundaries surrounding the crystal grains in the rare earth sintered magnet body is higher than the ratio of R2 to the sum of R1 and R2 in the crystal grains, and the concentration of R2 increases from the central portion of the rare earth sintered magnet body toward the surface of the rare earth sintered magnet body. In addition, the degree of unevenness in residual magnetic flux density on the surface of the rare earth sintered magnet body is smaller than 3.0%.
摘要:
The present invention provides a sintered magnet having superior residual magnetic flux density and coercive force. The sintered magnet of the present invention comprises a group of R-T-B based rare earth magnet crystal particles 2 having a core 4 and a shell 6 covering the core 4, the mass ratio of a heavy rare earth element in the shell 6 is higher than the mass ratio of a heavy rare earth element in the core 4, and the thickest part of the shell 6 in the crystal particles 2 faces a grain boundary triple junction 1. A lattice defect 3 is formed between the core 4 and the shell 6.
摘要:
A rare earth sintered magnet 10 including a magnet body that includes a rare earth compound, and a protective layer on the magnet body, having a first layer and a second layer in that order from the magnet body side, wherein the surface portion of the magnet body has a higher heavy rare earth element content than the interior of the magnet body that is surrounded by the surface portion, the first layer includes a rare earth oxide, the mass ratio of the heavy rare earth element being 1 or greater with respect to the light rare earth element, and the second layer includes an oxide containing iron and/or boron which is different from the rare earth oxide, the second layer having a lower rare earth oxide content than the first layer.
摘要:
A rare earth sintered magnet 10 including a magnet body that includes a rare earth compound, and a protective layer on the magnet body, having a first layer and a second layer in that order from the magnet body side, wherein the surface portion of the magnet body has a higher heavy rare earth element content than the interior of the magnet body that is surrounded by the surface portion, the first layer includes a rare earth oxide, the mass ratio of the heavy rare earth element being 1 or greater with respect to the light rare earth element, and the second layer includes an oxide containing iron and/or boron which is different from the rare earth oxide, the second layer having a lower rare earth oxide content than the first layer.