Hitachi, Ltd.

Toyota Jidosha Kabushiki Kaisha

Tohoku University

Mec International Co., Ltd.

Kyosuke Yoshimi

Yutaka Sato

Takeshi Matsuo

Yuichi Furukawa

Satoshi Hirano

Takaaki Niinomi

Seung Hwan Park

Setsuyu Hayakawa

Hiroyuki Kokawa

Mitsuo Suzuki

A metal material that is, without using expensive apparatus, carburized in a low temperature region where crystal grains do not grow so much, and a producing method of the metal material are provided. A metal material mainly containing iron, wherein a surface of the metal material is subjected to a carburization treatment by a treatment using fullerenes as a carbon source.

Carburized metal material and producing method thereof

An object of the present invention is to provide a friction stir welding tool which enables friction stir welding of a wide range of materials, from low-melting temperature metallic materials including aluminum to high-melting temperature metallic materials including steel. An entire friction stir welding tool or a tool tip including a pin is made of Mo alloy having a dual phase microstructure of Mo and intermetallic compound MoSiB. It is desirable that the Mo alloy be composed of 6.0 to 10.0 mol % of Si, 10.0 to 20.0 mol % of B, and 20 to 60% of Mo-phase volume content. This Mo alloy tool has excellent high-temperature strength and wear-resistance properties and hardly deform and wear when used for the welding of steel.

Friction stir welding tool and friction stir welding apparatus

Growing community of inventors

Sendai, Japan

Kyosuke Yoshimi