Hitachi, Ltd.

Hitachi Metals, Ltd.

Hitachi, Ltd., Research Development Corporation of Japan

Joo Ishihara

Toshio Ogawa

Hideo Suzuki

Yasuo Suzuki

Katsuzo Aihara

Isao Ikuta

Naofumi Tada

Masaichi Nagai

Sadami Tomita

Takeo Tamamura

Tetsuroh Minemura

Ken-ichi Sato

Masashi Era

A method of producing a long-life roll for a rolling mill manufacturing a rolled sheet having brightness. At least the surface of the roll barrel is made of steel containing carbide, the average grain size of which is not greater than 0.6 .mu.m, and the areal ratio of the carbide in the matrix is 6-30%. The roll is manufactured by canning steel powder produced by an RST process into a metal cylindrical container in a vacuum, sintering the powder in the cylindrical container by hot isostatic pressing, working the sintered body into the cnfiguration of a roll by machining and further giving it a heat treatment and finishing work. The roll and a rolling mill incorporating the roll are also disclosed.

Roll for a rolling mill, method of producing the same and the rolling

A matrix for magnetic separators which comprises wire or ribbon of a crystalline magnetic alloy having a fine-grained structure and a supersaturated solid solution structure.

Magnetic separator matrix of cut pieces of an elongated crystalline

A method of producing a composite material of and Nb or V used for a superconductive wire comprises vacuum - melting two kinds of raw materials, 70 wt % Cu and 30 wt % Nb or V to form a melt; scattering the melt by a rotating disc to form a plurality of fine droplets each of which includes Cu and Nb or V at substantially the same compounding rate as the raw materials; and cooling rapidly the fine droplets by spraying an inert gas onto the scattering droplets thereby providing particulate bodies each of which dendrites of Nb or V are precipitated in Cu. The fine particles are compression - molded to form a molded product. The molded product is sintered to form an ingot in which the dendrites of Nb or V are dispersed homogeneously in the Cu base. The ingot is used for producing a superconductive wire, namely, it is subjected to cold rolling to reduce its sectional area, coating with Su or Ga, and diffusion heat-treating the wire to form Nb.sub.3 Sn or V.sub.3 Ga in the Cu base, whereby a superconductive wire is provided in which Nb.sub.3 Sn or V.sub.3 Ga are homogeneously dispersed in the Cu base.

Method of producing material for superconductor

An apparatus for producing a metal ribbon has a rotary roll. Molten metal is poured from a heated nozzle onto the outer peripheral surface of the roll to form a solidified metal ribbon on the roll surface. To facilitate easy separation of the metal ribbon from the roll surface, a jet of a non-oxidizing gas is directed to the point of separation of the ribbon from the roll surface. The roll surface just upstream of the metal-pouring nozzle is enclosed by a cover the inside of which is evacuated to assure intimate contact of the poured metal with the roll surface and thus improve cooling of the poured metal. A heater is provided in the cover to heat the roll surface just upstream of the metal-pouring nozzle for thereby removing dew droplets and ambient gases from the roll surface whereby the formation of depressions or recesses in the roll-containing ribbon surface is prevented.

Apparatus for producing metal ribbon

Growing community of inventors

Hitachi, Japan

Joo Ishihara