An aluminum vacuum chamber for the bending magnet of the SRRC synchrotron light source

Abstract

A bending magnet vacuum chamber of the SRRC synchrotron light source has been studied. The A6061-T6 aluminum alloy was chosen as the chamber material, and a numerical-controlled oil-less machining process was applied for the fabrication. The AES and SIMS surface analysis methods have been applied to analyse the contaminations on the surface of this chamber. After a TIG welding process, the deformation of this chamber was ⪅ 0.3 mm per meter length. The ‘concentrated’ pumping method was designed and a distributed ion pump was also built in this chamber. A static vacuum of ⩽ 1 × 10 −10 torr has been reached after a bakeout of 150°C. In addition to the above-mentioned works, the residual gases of the system and the pumping speeds of the distributed ion pump were also measured.