Abstract
Relation between extruded aluminum surface structure and vacuum property was studied and the following results were obtained.
1) 6063 alloy extruded with the conditions of preventing air from entering inside of pipe and of taking in mixture gas of Ar+O2, showed low outgassing rate (2×10-13Torr•l/s•cm2) by only 150°C, 24h baking. And the inside of pipe showed pumping effect which is considered to adsorb gas molecules in space. 2) The material extruded in mixture gas of Ar+O2 by aluminum alloy of which magnesium is removed from 6063 alloy, showed the higher outgassing rate (1×10-12Torr•l/s•cm2) than that of 6063 alloy, in addition, showed no pumping effect. 1060 alloy extruded in mixture gas of Ar+O2 showsd the lower outgassing rate (7×10-14Torr•l/s•cm2), but showed no pumping effect. In this way, we could obtain new functional surface which has extremely low outgassing rate by controlling atmosphere in extrusion.
