Sumitomo Special Metals Co., Ltd.

Neomax Co., Ltd.

Hiroshi Hashikawa

Osamu Yamashita

Shuhei Okumura

Seiichi Kohara

Tsunekazu Saigo

Hirokazu Kitayama

In a process for handling green compacts made from a rare earth metal-based magnetic alloy powder by a press machine to slide, on a sintering support plate, the green compacts, the support plate used has a surface roughness degree Ra in a range of 0.6 to 47 &#x3bc;m. At a first step, the green compacts are disposed in a first position near a final transport position, and at a second step, the said green compacts disposed in the first position are slid on the sintering support plate and disposed in the final transport position. Thus, by using the support plate having a surface roughness degree in a particular range, the green compacts made from the rare earth metal-based magnetic alloy powder can be sintered without occurrence of the deposition of the green compacts to the support plate, the chipping of the green compacts and the like. In addition, the efficiency of operation of the press machine can be increased.

Process for handling powder green compacts, and rare earth metal-based magnet

In a process for handling green compacts made from a rare earth metal-based magnetic alloy powder by a press machine to slide, on a sintering support plate, the green compacts, the support plate used has a surface roughness degree Ra in a range of 0.6 to 47 &mgr;m. At a first step, the green compacts are disposed in a first position near a final transport position, and at a second step, the said green compacts disposed in the first position are slid on the sintering support plate and disposed in the final transport position. Thus, by using the support plate having a surface roughness degree in a particular range, the green compacts made from the rare earth metal-based magnetic alloy powder can be sintered without occurrence of the deposition of the green compacts to the support plate, the chipping of the green compacts and the like. In addition, the efficiency of operation of the press machine can be increased.

Process for handling powder green compacts and rare earth metal-based magnet

The purpose of this invention is to present fabrication methods and equipment for granulated powders whereby, the reaction between the R--Fe--B-type or R--Co-type rare earth containing alloy powders and the binder is controlled, the residual oxygen and carbon content of the sintered products after sintering is reduced, and whereby it is possible to obtain isotropic or anisotropic granulated powders having good powder flowability and lubrication properties when molding. After stirring a slurry of rare earth containing alloy powders formed by adding a binder consisting of water and at least one of either methyl cellulose, polyacryl amide or polyvinyl alcohol, and mixing, oriented liquid droplets are formed by applying a magnetic field to the slurry to orientate the said powder particles and spraying within the chamber of a spray dryer apparatus. By instantaneously dry solidifying these anisotropic granulated powders, it is possible to fabricate spherical granulated powders with good magnetic properties and a high flowability whereby the flowability and lubrication properties of the powder at the time of compression molding are improved, as well as improving the molding cycle and the dimensional precision of the molded product.

Fabrication methods and equipment for granulated powders

The purpose of this invention is to present fabrication methods and equipment for granulated powders whereby, the reaction between the R-Fe-B-type or R-Co-type rare earth containing alloy powders and the binder is controlled, the residual oxygen and carbon content of the sintered products after sintering is reduced, and whereby it is possible to obtain isotropic or anisotropic granulated powders having good powder flowability and lubrication properties when molding. After stirring a slurry of rare earth containing alloy powders formed by adding a binder consisting of water and at least one of either methyl cellulose, polyacryl amide or polyvinyl alcohol, and mixing, oriented liquid droplets are formed by applying a magnetic field to the slurry to orientate the said powder particles and spraying within the chamber of a spray dryer apparatus. By instantaneously dry solidifying these anisotropic granulated powders, it is possible to fabricate spherical granulated powders with good magnetic properties and a high flowability whereby the flowability and lubrication properties of the powder at the time of compression molding are improved, as well as improving the molding cycle and the dimensional precision of the molded product.

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Osaka, Japan

Hiroshi Hashikawa