チタン製真空容器の真空特性 Vacuum Characteristics of Titanium Chamber
Surface roughness and vacuum characteristic of pure titanium plates modified by buffing and electrolytic polishing were investigated by atomic force microscopy (AFM) and thermal desorption spectroscopy. Surface roughness of the titanium plates decreases after polishing and a typical value of the surface roughness (Ra) is 12.9 nm at 10 × 10 μm range by AFM. The magnitudes of ion currents due to outgassing such as H<SUB>2</SUB>, H<SUB>2</SUB>O, N<SUB>2</SUB> and CO<SUB>2</SUB> from the polished titanium plates are smaller than those from the polished stainless steel plates by a factor of 10. The polished titanium is used to prepare a vacuum chamber with O-ring seals. The chamber is pumped down by a turbo molecular pump and the pressure reaches 1.2 × 10<SUP>-7</SUP> Pa after a 78 h baking at 150°C.
真空 42(3), 200-203, 1999-03
The Vacuum Society of Japan