Nkk Corporation

Kitagawa Industries Co., Inc.

The Tokai University Juridicial Foundation

Jfe Steel Corporation

Moriaki Ono

Tsuyoshi Shiozaki

Yukio Shinbo

Makoto Kabasawa

Hiroshi Matsuda

Takeshi Fujita

Yukio Sekine

Yuji Yamasaki

Yasunobu Nagataki

Kohei Hasegawa

Yoshihiro Hosoya

Masaya Morita

Fusato Kitano

Toru Inazumi

Masanori Ohmura

Kenichi Iwazaki

Akio Sato

Yutaka Nagahama

Shigeyoshi Kosuge

Kyoji Tachikawa

Shigeyoshi Kosuga

A high strength cold rolled steel sheet consists essentially of 0.0040 to 0.01% C, not more than 0.05% Si, 0.1 to 1.0% Mn, 0.01 to 0.05% P, not more than 0.02% S, 0.01 to 0.1% sol.Al, not more than 0.004% N, 0.01 to 0.14% Nb, by weight, and a balance of substantially Fe and inevitable impurities, and having an n value of not less than 0.21 calculated from two points (1% and 10%) of nominal strain determined by the uniaxial tensile test, and a method for manufacturing the cold rolled steel sheet. The high strength cold rolled steel sheet has excellent combined formability, resistance to embrittlement during secondary operation, formability at welded portions, and anti-burring performance, and has a desirable surface appearance and uniformity of material in a coil, and thus can be desirably used for automobile exterior panels.

High strength cold rolled steel sheet and method for manufacturing the same

The present invention relates to a very low C&mdash;Nb cold rolled steel sheet giving 340 to 440 MPa of tensile strength. For example, the cold rolled steel sheet consists essentially of 0.0040 to 0.01% C, not more than 0.05% Si, 0.1 to 1.0% Mn, 0.01 to 0.05% P, not more than 0.02% S, 0.01 to 0.1% sol.Al, not more than 0.004% N, 0.01 to 0.14% Nb, by weight, and balance of substantially Fe and inevitable impurities, and has not less than 0.21 of n value calculated from two points (1% and 10%) of nominal strain determined by the uniaxial tensile test, and relates to a method for manufacturing the cold rolled steel sheet. The present invention provides a high strength cold rolled steel sheet for automobile exterior panels having excellent combined formability, resistance to embrittlement during secondary operation, formability at welded portions, anti-burring performance, good surface appearance, and uniformity of material in a coil.

A laser welded steel pipe having a weld zone containing a steel pipe containing 0.01 to 0.2 weight % C, 1 weight % or less S, 0.05 to 2 weight % Mn and 6 weight % or less Mn. The weld zone has a melted and solidified metal structure containing carbon and oxygen which satisfy the following equations:

Laser-welded steel pipe and method therefor

A laser-welded steel pipe includes: a steel pipe consisting essentially of C in an amount of 0.01 to 0.5 wt. %, Si in an amount of 1 wt. % or less, Mn in an amount of 0.05 to 2 wt. % and Cr in an amount of 6 wt. % or less; and a weld zone having a melted and solidified metal structure containing carbon and oxygen. The carbon content, �C wt. %!, and the oxygen content, �O wt. %!, in the melted and solidified metal structure satisfies the following equations:

Laser-welded steel pipe

A method of producing a welded steel pipe which comprises: (a) forming a steel strip having two edges in a cylindrical form so that the two edges face each other; (b) preheating the two edges of the steel strip to a temperature of a melting point or less by applying a high frequency electric current to the two edges; (c) pressing the two edges of the steel strip towards each other by contact with squeeze rolls to form a joint portion including a joint line; (d) radiating a high density energy beam sufficient to fuse a full thickness of the steel strip to a portion adjacent to a squeeze point to weld the joint portion; and (e) controlling an upset by applying the squeeze rolls sufficiently to reduce weld defects.

Method for producing a steel pipe using a high density energy beam

A method for manufacturing a superconducting article, comprising the steps of: forming a first layer comprising a mixture of LnBa.sub.2 Cu.sub.3 O.sub.x and Ln.sub.2 BaC oxid, on the surface of a substrate, said Ln being an optional rare earth element; then locally and sequentially/heating and melting the first layer to locally and sequentially form a molten pool of the mixture of the first layer, and causing the molten pool of the first layer to locally and sequentially solidify, thereby arranging the a-b plane of the crystal of the mixture of the first layer in parallel with the surface of the substrate; then forming a second layer comprising a mixture of at least CuO and BaCuO.sub.2 on the surface of the first layer; and then melting the mixture of the second layer to cause the resultant melt of the mixture of the second layer to diffusion-react with Ln.sub.2 BaCu oxide, in the first layer so as to convert the first and second into a film of a superconducting substance comprising LnBa.sub.2 Cu.sub.3 O.sub.x, in which the a-b plane of the crystal thereof is arranged in parallel with the surface of the substrate; thereby manufacturing a superconducting article comprising the substrate and the film of the superconducting substance formed on the surface of the substrate.

Method for manufacturing oxide superconducting article

A method for manufacturing a superconducting article, comprising the steps of: forming a first layer comprising a mixture of LnBa.sub.2 Cu.sub.3 O.sub.x and Ln.sub.2 BaCuO.sub.x ' on the surface of a substrate, said Ln being an optional rare earth element; then forming a second layer comprising a mixture of at least CuO and BaCuO.sub.2 on the surface of the first layer; and then melting the mixture in the second layer to cause the resultant melt of the mixture in the second layer to diffusion-react with Ln.sub.2 BaCuO.sub.x ' in the first layer so as to convert the first and second layers into a film of a superconducting substance comprising LnBa.sub.2 Cu.sub.3 O.sub.x ; thereby manufacturing a superconducting article comprising the substrate and the film of the superconducting substance formed on the surface of the substrate.

Method for manufacturing an oxide superconducting article

A magnetic shield which comprises: a plurality of metallic cylinders connected to each other in the axial direction thereof, each of the plurality of cylinders having at one end thereof an engaging section for receiving an end of an adjacent metallic cylinder to be connected thereto; and a film of a composite oxide superconducting material containing a Cu.sub.x O.sub.y -radical, formed on the entire inner surface of each of the plurality of cylinders, including the inner surface of the engaging section thereof. The above-mentioned magnetic shield can easily be scaled up and has a high magnetic shielding effect.

Magnetic shield

Growing community of inventors

Tokyo, Japan

Moriaki Ono