Nippon Steel Corporation

Toho Kinzoku Co., Ltd.

Nippon Hardmetal Co., Ltd.

Hiroto Imamura

Hirokazu Taniguchi

Toru Ono

Michio Endo

Mitsuji Hirata

Koji Akafuji

Isao Arikata

Shigeki Ogura

Syoichi Sekiguchi

Masayuki Hashimura

Sakae Katayama

Tetsuo Sawashima

The present invention aims to provide a metal mold for glass, which needs not apply any swab in molding of glass, enabling no-swabbing glass forming. The alloy for the mold comprises by weight Cu: 10 to 80%, Al: 4 to 11%, Cr: 3 to 16%, Ni: 2 to 36%, and at least one rare earth element: 0.02 to 2.0% with the balance consisting of Fe and further comprises at least one member selected from the group consisting of Ti: Al%.times.0.5 to 2, V: Al%.times.0.2 to 1, Zr: Al%.times.0.1 to 0.3, and Nb: Al%.times.0.1 to 0.3. The alloy is gradually cooled from the solidification initiation temperature to 50.degree. C. at a cooling rate of 10.degree. C./ min. The surface of the mold is coated with an Al-containing coating or roughened to an average roughness of 0.3 to 5 .mu.m. A solid lubricating film is provided in a fitting portion of the mold, or alternatively a self-lubricating solid is embedded in the fitting portion of the mold.

Metal mold for glass forming

The present invention aims to provide a metal mold for glass, which needs not apply any swab in molding of glass, enabling no-swabbing glass forming. The alloy for the mold comprises by weight Cu: 10 to 80%, Al: 4 to 11%, Cr: 3 to 16%, Ni: 2 to 36%, and at least one rare earth element: 0.02 to 2.08 with the balance consisting of Fe and further comprises at least one member selected from the group consisting of Ti: Al %.times.0.5 to 2, V: Al %.times.0.2 to 1, Zr: Al %.times.0.1 to 0.3, and Nb: Al %.times.0.1 to 0.3. The alloy is gradually cooled from the solidification initiation temperature to 500.degree. C. at a cooling rate of 10.degree. C./min. The surface of the mold is coated with an Al-containing coating or roughened to an average roughness of 0.3 to 5 .mu.m. A solid lubricating film is provided in a fitting portion of the mold, or alternatively a self-lubricating solid is embedded in the fitting portion of the mold.

A cemented carbide tool of excellent wear resistance and fracture resistance includes a substrate of cemented carbide, and a ceramic coating layer by chemical vapor deposition. The thickness of the layer is in the range of between 2 .mu.m to 20 .mu.m, and the layer has cracks of such a depth that the cracks extend perpendicularly from a surface of the layer to the substrate. The cracks are formed in a network-like pattern to minutely divide the layer. The average value of the depths of the cracks in a direction perpendicular to the surface of the layer is not less than the thickness of the layer and not more than a value equal to the coating thickness plus 5 .mu.m. The average value of widths of the cracks is not more than 2 .mu.m. The average value of intervals between the cracks is not less than 10 .mu.m and not more than 100 .mu.m.

Ceramics coated cemented-carbide tool with high-fracture resistance

Growing community of inventors

Kitakyushu, Japan

Hiroto Imamura