Seiko Epson Corporation

Cosmo System Corporation

Toshiyuki Ishibashi

Koji Akioka

Tatsuya Shimoda

Osamu Kobayashi

Ryuichi Ozaki

Atsunori Kitazawa

Ken Ikuma

Makoto Okeya

Norio Ito

Yasunori Ueki

Sumitaka Wako

Mitsuho Matsuzawa

A magnetic powder and a permanent magnet are provided which have magnetic properties enhanced by magnetic interaction. Disclosed are a magnetic powder comprising a mixture of two or more powders including a magnetic powder A (residual magnetic flux density: BrA, coercive force: HcA) and a magnetic powder B (residual magnetic flux density: BrB, coercive force: HcB) of which the residual magnetic flux densities and the coercive forces have the following relationships: BrA&gt;BrB and HcA&lt;HcB, and a bonded magnet or a sintered magnet produced from the magnetic powder, and a method for mixing magnetic powders and a process for producing a magnet.

Magnetic powder, permanent magnet produced therefrom and process for

A rare earth-iron series magnet formed from an alloy ingot using a one-step hot working process is provided. The alloy ingot includes between about 8 and 30 atomic percent of at least one rare earth element, between about 2 and 28 atomic percent of boron, less than about 50 atomic percent of cobalt, less than about 15 atomic percent of aluminum and the balance of iron and other impurities that are inevitably included during the preparation process. The alloy is cast to obtain a cast ingot and the hot working is performed on the cast ingot at a temperature of greater than about 500.degree. C. in order to make the crystal grains of the ingot fine and to align the axis of the grains in a desired direction.

Rare earth-iron series permanent magnets and method of preparation

Rare-earth bonded magnet composition, rare-earth bonded magnet and

A rare earth iron permanent magnet including at least one rare earth element, iron and boron as primary ingredients. The magnet can have an average grain diameter of less than or equal to about 150 .mu.m and a carbon content of less than or equal to about 400 ppm and a oxygen content of less than or equal to about 1000 ppm. The permanent magnet is prepared by casting a molten alloy. In one embodiment, the cast body is heat treated at a temperature of greater than or equal to about 250.degree. C. Alternatively, the material can be cast and hot worked at a temperature of greater than or equal to about 500.degree. C. Finally, the material can be cast, hot worked at a temperature of greater than or equal to about 500.degree. C. and then heat treated at a temperature of greater than or equal to about 250.degree. C. The magnets provided in accordance with the invention are relatively inexpensive to produce an have excellent performance characteristics.

Rare earth cast alloy permanent magnets and methods of preparation

Horizontal and vertical displacement detector of wire rope

A rare earth iron permanent magnet including at least one rare earth element, iron and boron as primary ingredients. The magnet can have an average grain diameter of less than or equal to about 150 .mu.m and a carbon content of less than or equal to about 400 ppm and content of less than or equal to about 1000 ppm. The permanent magnet is prepared by casting a molten alloy. In one embodiment, the cast body is heat treated at a temperature of greater than or equal to about 250.degree. C. Alternatively, the material can be cast and hot worked at a temperature of greater than or equal to about 500.degree. C. Finally, the material can be cast, hot worked at a temperature of greater than or equal to about 500.degree. C. and then heat treated at a temperature of greater than or equal to about 250.degree. C. The magnets provided in accordance with the invention are relatively inexpensive to produce an have excellent performance characteristics.

A rare earth iron permanent magnet including at least one rare earth element, iron and boron as primary ingredients. The magnet can have an average grain diameter of less than or equal to about 150 .mu.m and a carbon content of less than or equal to about 400 ppm and an oxygen content of less than or equal to about 1000 ppm. The permanent magnet is prepared by casting a molten alloy. In one embodiment, the cast body is heat treated at a temperature of greater than or equal to about 250.degree. C. Alternatively, the material can be cast and hot worked at a temperature of greater than or equal to about 500.degree. C. Finally, the material can be cast, hot worked at a temperature of greater than or equal to about 500.degree. C. and then heat treated at a temperature of greater than or equal to about 250.degree. C. The magnets provided in accordance with the invention are relatively inexpensive to produce an have excellent performance characteristics.

Growing community of inventors

Suwa, Japan

Toshiyuki Ishibashi