| 摘要 |
PURPOSE:To release adsorbed gases from an Al surface and to prevent the decrease in the degree of vacuum in the stage of producing an Al member to be used in a high vacuum part by subjecting the surface facing the vacuum part to surface working such as cutting in a gaseous atmosphere contg. oxygen without bringing the same into contact with the atmosphere contg. moisture. CONSTITUTION:The surface facing a vacuum part of an Al member as a material facing the vacuum member of a high vacuum device is cut or ground to expose the fresh surface in a gaseous atmosphere contg. 0.5-30vol% O2 and consisting of the balance Ar, He or gaseous N inert with Al or a vacuum contg. a slight amt. of O2 in the stage of producing said member. The exposed surface of Al contacts with O2 without contacting with the atm. air contg. moisture and is therefore oxidized by which an Al2O3 film is formed on the surface. Since no hydrated oxide is formed on the surface of the Al, moisture, gaseous hydrocarbon and gases such as CO2, CO, etc. which decrease the degree of vacuum are not generated in vacuum. The high degree of vacuum is thus maintained. |
