It is our great pleasure to welcome all of you to ICAA12, the 12th International Conference on Aluminium Alloys in Yokohama, Japan. The ICAA, which is held every two years, is the leading international conference on aluminium alloys, ranging from production, processing, and alloy development to applications. The first conference was held in Charlottesville, Virginia, in 1986 to celebrate the centennial of the Hall-Héroult process, which heralded the commercial application of aluminium alloys. Subsequent conferences have been held in: Beijing 1990, Tronheim 1992, Atlanta 1994, Grenoble 1996, Toyohashi 1998, Charlottesville 2000, Cambridge 2002, Brisbane 2004, Vancouver 2006, and Aachen 2008. In 2010, ICAA comes to Japan again and is being held in Yokohama.

Aluminium alloys are extremely noticeable lightweight materials that meet various needs of society, and thus are of great interest to people. In ICAA12, we are organizing special technical sessions on the latest developments and applications of aluminium alloys together with key topics of fundamental importance.

We also have specially planned to exhibit aluminium industries and technological developments in Japan. We expect to see many of the friends we have met over the years, to meet new colleagues, and to learn from the presentations, poster sessions, and the formal and informal discussions. Yokohama, the representative international city, is an ideal place for researchers and engineers involved in aluminium alloys to meet together for lively discussions and to chart the future direction of aluminium.

The ICAA12 Proceedings are published on a USB flash drive for the convenience of participants. You do not need to carry heavy proceedings books during the conference and you can refer the paper you want on your PC at the conference site. Thanks to all your contributions, the number of papers stored here is over 400 and the papers came from about 30 countries. These are far better than we expected. We would like to thank the authors of the papers and also the referees who provided great assistance to improve the quality of the papers. The editorial committee of Materials Transactions is planning to publish a special issue on “Aluminium Alloys 2010” in May 2011. The author who presented his or her work in the proceedings has the privilege of publishing the polished-up papers in a special issue.

Finally we would like to express our thanks to The Japan Institute of Light Metals for organization and The Light Metal Educational Foundation, Inc., Japan Society for the Promotion of Science, Japan Aluminium Association, Japan Light Metal Welding & Construction Association, Amada Foundation for Metal Work Technology, Showa Denko K.K., Mitsubishi Aluminum Co., Ltd., Nippon Light Metal Company, Ltd., Sumitomo Light Metal Industries, Ltd., Furukawa-Sky Aluminum Corp., Kobe Steel, Ltd., and the City of Yokohama for their cooperation. We would also like to express our thanks for The Organizing Committee and The Steering Committee, the Secretariat of ICAA12 (ICS Convention Design, Inc.) and the Secretariat of The Japan Institute of Light Metals (Tomoya Ohzono, Sonomi Maeda and Akiko Kimura) for their commitment to and assistance with the present conference.

Shinji Kumai (Tokyo Institute of Technology)
Osamu Umezawa (Yokohama National University)
Yoshimasa Takayama (Utsunomiya University)
Takayuki Tsuchida (Nippon Light Metal Company, Ltd.)
Tatsuo Sato (Tokyo Institute of Technology)