EXAMPLES OF ALUMINUM USE IN JAPAN - SPECIAL TREATMENTS OF ALUMINUM FOR ULTRAHIGH-VACUUM APPLICATIONS

Aluminium and aluminium alloy are preferred materials for ultrahigh vacuum and extremely high vacuum systems. Examples are described for aluminium alloy use in Japan such as beam chambers for electron storage rings, extremely high vacuum system, heat treatment furnace, multi-chambers for semiconductor processes, long pipe for laser gravitational wave detection, and honeycomb structures for space application. This paper presents aluminium alloy materials, surface treatments, welding, outgassing, and suitable ultrahigh vacuum components of flange, bellows, valves, pumps and gauges. Extremely fast pump-down system from atmosphere to 10(-8) Torr in 150 seconds using super-dry nitrogen is demonstrated.