Kobe Steel, Ltd.

Kabushiki Kaisha Kobe Seiko Sho

Yoshio Itsumi

Hideto Oyama

Yasuyuki Fujii

Keitaro Tamura

Akio Okamoto

Akihisa Fujita

Kazuki Sakamoto

Shogo Murakami

Takeshi Kudo

Koichi Akazawa

Tadashige Nakamoto

Kayo Yamamoto

Takashi Konno

Keita Sasaki

Norikazu Matsukura

Jun Suzuki

Disclosed is a titanium or titanium alloy plate rolled in one direction, wherein a lubricating film is coated on the surface and the coefficient of sliding friction of the lubricating film-coated surface is controlled to less than 0.15. The elongation (L-El) of the titanium or titanium alloy plate in the rolling direction and the r value (T-r) in the direction perpendicular to the rolling direction have the following relation (1).(-)/(-)&#x2267;0.07&#x2003;&#x2003;(1)

Titanium or titanium alloy plate excellent in balance between press formability and strength

Heat exchanger tube

An original plate material for a heat-exchanging plate fabricated by press working and a method for fabricating the original plate material are provided. An original plate material for a heat-exchanging plate is a flat plate material made of titanium on the surface of which convex parts and concave parts are formed, and the heat-exchanging plate is fabricated by press working the original plate material. The convex parts and the concave parts are formed in a manner such that the shape parameter defined by (Rz&#xd7;L/P) is 12 &#x3bc;m or less, where Rz (&#x3bc;m) denotes the height of the convex parts, L (&#x3bc;m) denotes the width of the concave parts, and P (&#x3bc;m) denotes the pitch between neighboring convex parts.

Original plate material for heat-exchanging plate, and method for fabricating original plate material for heat-exchanging plate

Plate for heat exchanger

Disclosed is a pure titanium sheet having a strength corresponding to JIS Grade 2 level (215 MPa in terms of 0.2% yield strength) or more and having satisfactory stamping formability. The pure titanium sheet includes titanium and inevitable impurities, has a 0.2% yield strength of 215 MPa or more, has an average grain size d of its structure of 25 &#x3bc;m or more and 75 &#x3bc;m or less, and has a hexagonal crystal structure, in which respective grains in the hexagonal crystal structure have an average of Schmidt factors (SF) of (11-22) twins with a rolling direction as axes, and the average Schmidt factor (SF) and the average grain size d satisfy following Expression (1):0.055&#x2266;[SF/&#x221a;]&#x2266;0.084&#x2003;&#x2003;(1).

Pure titanium sheet excellent in balance between stamping formability and strength

A titanium alloy product according to the present invention: has a strength level higher than that of an existing titanium alloy product; can be successfully cold rolled (coil rolled); and is also provided with workability. In the titanium alloy product according to the invention, expensive alloy elements are not essentially required, and hence cost can be suppressed. The titanium alloy product according to the invention includes Al equivalent represented by (Al+10O (oxygen)): 3.5 to 7.2% (% by mass, the same hereinafter), Al: more than 1.0% and 4.5% or less, O: 0.60% or less, Fe equivalent represented by (Fe+0.5Cr+0.5Ni+0.67Co+0.67Mn): 0.8% or more and less than 2.0%, and one or more elements selected from the group consisting of Cu: 0.4 to 3.0% and Sn: 0.4 to 10%, in which the balance is Ti and unavoidable impurities.

Titanium alloy product having high strength and excellent cold rolling property

Growing community of inventors

Kakogawa, Japan

Yoshio Itsumi