Upper bound to the outgassing rate of metal surfaces

An upper bound to the outgassing rate of low-surface-area metal surfaces after an atmospheric exposure is deduced from a recently derived model. The result is Q/sub max/=1.72 x 10-5/t (Torr l)/(s cm2) where t is in seconds. Comparisons of outgassing data with this estimate are made for (1) various low-surface-area materials, (2) a given surface at elevated temperatures, and (3) a variation in the real pumping speed for a particular surface. Q/sub max/ has been found to be an upper bound to the outgassing data under a variation of the above parameters provided that the material is operated at approximately-less-than100degreeC for times between 15 min and 7 days