Riken Corporation

Other

Nobuhide Itoh

Hitoshi Ohmori

Manabu Yamada

Susumu Shimizu

Shinji Ishii

Nobuyuki Nagato

Kiyoshi Imai

Yutaka Yamagata

Kotaro Yano

Naoki Oyanagi

Toshio Kasai

Masayuki Ishii

Kineo Kojima

Toshiro Karaki-Doy

Junichi Uchino

Toshiaki Uno

Kenichiro Horio

The present invention comprises a metal bond grind stone having a flat plate portion and a tapered portion ; an electrode opposed to the metal bond grind stone with a gap therebetween; voltage applying means for applying a direct-current pulse voltage between the metal bond grind stone and the electrode; conductive liquid supplying means for supplying a conductive liquid between the metal bond grind stone and the electrode; and grind stone moving means for moving the metal bond grind stone in a direction orthogonal to the shaft center thereof, and an ingot of a single crystal SiC is thereby cut at the tapered portion of the metal bond grind stone and the cut surface is then specular-worked at the flat plate portion

Method and apparatus for cutting and grinding single crystal SiC

An ELID centerless grinding apparatus comprising: a blade for horizontally supporting a rotator workpiece and and a regulating wheel driven to rotate around a horizontal shaft center. An outer surface of the workpiece is subjected to ELID grinding by using a conductive grinding wheel . An outer peripheral portion of the wheel includes a conductive elastic member and abrasion resisting particles . An electrolytic electrode is provided in close vicinity to an outer peripheral surface of the wheel . An electrolytic power supply applies an electrolytic voltage between the electrolytic electrode and the wheel. A conductive electrolytic fluid is flow between the electrode and the wheel and the member is removed by the electrolytic dressing to cause the abrasion resisting particles to project, while the particles are brought into contact with the outer peripheral surface of the workpiece to rotate around its shaft center. Consequently, the coefficient of friction of the outer peripheral surface shape of the regulating wheel with respect to the workpiece can be maintained more or less constant during the grinding process of the workpiece.

ELID centerless grinding apparatus

There is provided a conductive grinding wheel rotating centering on a vertical shaft center and including a horizontal working surface , and the grinding wheel comprises a conductive base member formed of an integrally molded flat plate, and a plurality of fan-shaped segments detachably attached to the base member to entirely constitute the annular working surface. Each segment comprises a base metal directly attached to the base member and a grinding wheel part formed on the surface of the base metal. Moreover, the grinding wheel part comprises a recessed groove for partitioning the working surface into a plurality of working areas , and an electrolytic fluid supply hole for directly supplying the electrolytic fluid to the respective working areas, so that the electrolytic fluid is supplied to the respective electrolytic fluid supply holes through the base member.

Grindstone for ELID grinding and apparatus for ELID surface grinding

A metal bond grinding wheel,having a horizontal working surface,a holding and rotating means,for a workpiece having a horizontal supporting surface,opposite to said working surface,a voltage applying means,having the metal bond grinding wheels and an electrode,installed oppositely to the working surfaces in an uncontacted state and applying a pulsed voltage between them, a grinding fluid feeding means,for feeding an electroconductive grinding fluid to the working surfaces are installed. The holding and rotating means,holds and rotate a disk-like magnetic disc substrate,or a truing grinding wheel,to closely contact to its supporting surface, has constitution capable of moving horizontally and vertically, wherein a surface for working,is processed to yield a flat surface on the machine, subsequently, alternative operations on the machine are carried out for grinding of the supporting surface,of the holding and rotating means of the workpiece simultaneously with electrolytic dressing of the metal bond grinding wheel and grinding of the magnetic disc substrate,attached to the holding and rotating means of the workpiece.

Apparatus and method for mirror surface grinding of magnetic disc substrate

The method disclosed here comprises the steps of (a) mixing metal powder, a resin, abrasive grains, and a solid reducing agent at the normal (room) temperature through the melting point of the reducing agent to form a mixture and (b) molding and baking the mixture at the melting point of the reducing agent through that of the metal powder. The solid reducing agent is a fatty acid, preferably stearic acid having a volume ratio of 5 to 20% with respect to the metal powder. With is, it is possible to make metal-resin bond grindstones that give such high-quality mirror surfaces that have conductivity fit for ELID grinding and are not liable to have chippings or scratches and also have an Rmax value of approximately 3 nm or less.

Metal-resis bond grindstone and method for manufacturing the same

Growing community of inventors

Hitachi, Japan

Nobuhide Itoh