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An experimental setup that allows quantitative measurements of the temperature programmed desorption of different gases from any sample is described. The samples to be analyzed are uniformly heated to temperatures up to 2100 K by electron bombardment from the rear side at a rate of about 10 K/s. The temperature is controlled and can be measured on the front side by a pyrometer. The gases released from a sample are measured with a quadrupole mass spectrometer according to the partial pressure change in the residual gas. In order to get quantitative results the equipment is calibrated for different gases. The facility was tested with measurements of the hydrogen inventory and desorption temperatures for graphite samples from the vessel walls of the fusion experiment ASDEX Upgrade.

Stainless steel 316 specimens have been implanted with deuterium ions at 7 keV up to doses of 2×1018 D/cm2 at −120°C. Trapped quantities and depth profiles of the implanted atoms have been determined using the 3He (d,p) 4He nuclear reaction, using both the product particles for making the analyses. Up to doses of 5×1017 D/cm2 the implanted deuterons were retained within the analyzing zone, but at higher fluences the amounts retained no longer increased linearly with the bombardment dose. Deuterium to metal atom ratios of nearly 1:1 were observed. The density of retained deuterium was not a function of holding time at −120°C, but upon warming, the loss of deterium could be measured. At roughly −50°C the rate of loss was a maximum, and by +40°C only a few percent of the original amount of deuterium remained.