AVS 63rd International Symposium & Exhibition
    Vacuum Technology Tuesday Sessions
       Session VT-TuM

Paper VT-TuM6
Outgassing of UHV Stainless Steel Cans

Tuesday, November 8, 2016, 9:40 am, Room 104C

Session: Vacuum Pumping and Material Outgassing
Presenter: Lily Wang, Los Alamos National Laboratory
Authors: L.L. Wang, Los Alamos National Laboratory
P.D. Honnell, Los Alamos National Laboratory
Correspondent: Click to Email
UHV stainless steel cans are used to contain material samples in our experiments to study how the materials age under accelerated thermal conditions. In addition to characterizing the material properties after the thermal aging treatment, we also measure the amount of gas released during these thermal aging runs and analyze the off gas collected. In preparing for the experiments, the stainless steel cans were first vacuum-baked at 150°C to remove adsorbed moisture. The vacuum-baked cans were then brought into a dry nitrogen glovebox where the samples were loaded into these cans. The experiments were conducted in static vacuum at various temperatures ranging from 25 to 145°C for a duration ranging from 25 days to several years. The pressure of the gas accumulated in the sample can was measured with a capacitance diaphragm gauge. At each temperature, an empty UHV stainless steel can was also measured. Stainless steel contains dissolved hydrogen that diffuses out and contributes background outgas in vacuum systems. This talk will present the gas evolution results obtained from these empty cans and discuss how this stainless steel outgassing affects our gas evolution measurements.