The authors investigated the outgassing rates and fluxes of vacuum chambers constructed from common 304L stainless steel vacuum components and subjected to heat treatments. Our goal was to obtain H2 outgassing flux on the order of 10−11 Pa l s−1cm−2 or better from standard stainless steel vacuum components readily available from a variety of manufacturers. The authors found that a medium-temperature bake in the range of 400 to 450°C, performed with the interior of the chamber under vacuum, was sufficient to produce the desired outgassing flux. The authors also found that identical vacuum components baked in air at the same temperature for the same amount of time did not produce the same low outgassing flux. In that case, the H2 outgassing flux was lower than that of a stainless-steel chamber with no heat treatment, but was still approximately 1 order of magnitude higher than that of the medium-temperature vacuum-bake. Additionally, the authors took the chamber that was subjected to the medium-temperature vacuum heat treatment and performed a 24-h air bake at 430°C. This additional heat treatment lowered the outgassing rate by nearly a factor of two, which strongly suggests that the air-bake created an oxide layer which reduced the hydrogen recombination rate on the surface. []
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机译：作者研究了由常见的304L不锈钢真空组件构成并经过热处理的真空室的除气速率和通量。我们的目标是从标准不锈钢真空中获得10 −11 Pa ls −1 cm −2 或更高等级的H2脱气通量各种制造商容易获得的组件。作者发现，在腔室内部在真空下进行的400至450°C的中温烘烤足以产生所需的除气通量。作者还发现，在相同温度下于空气中烘烤相同时间的相同真空组件不会产生相同的低脱气通量。在那种情况下，H 2的放气通量低于未经热处理的不锈钢室的通气量，但仍比中温真空烘烤的通气量高约1个数量级。此外，作者将室进行了中温真空热处理，并在430°C下进行了24小时的空气烘烤。这种额外的热处理将除气速率降低了近两倍，这强烈表明空气烘烤会形成氧化物层，从而降低表面上的氢复合率。 []
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