Toto Ltd.

Katsuaki Nakamura

Masatoshi Enoki

Toru Uchida

Hachihei Watanabe

Tatsuo Matsukuma

Yuji Matsuo

Nobuyuki Ashie

Tsuguya Okubo

Hiromi Katahira

Takayoshi Yanagida

Toshiyuki Iwao

Ryuji Matsubara

Akira Yubisui

An object is to improve machinability and polishability of a brass material prepared through cold working, particularly in a brass pipe material. Before cold working, by having an &agr; phase making heat treatment step for increasing an area ratio of an &agr; phase, cold ductility can be ensured at the time of cold working. Also, after cold working, by having a &bgr; phase making heat treatment step for increasing an area ratio of a &bgr; phase, a brass material excellent in machinability and polishability can be provided.

Brass material, brass tube and their production method

A brass for forging which has an apparent Zn content of 37 to 50 wt % and contains 0.5 to 7 wt % Sn. The brass has a microstructure of at least an &agr; phase and a &ggr; phase at a temperature of 300 to 550&deg; C. and has crystal grain sizes which are made fine. A process for preparing brass involving making the crystal grain size of brass material fine and plastic working the brass material at 300 to 550&deg; C.

Metal material, brass and method for manufacturing the same

Valve device using pipes and method of manufacturing it

Growing community of inventors

Kitakyushu, Japan

Katsuaki Nakamura