Quantitative determination of the bulk deuterium content of zirconium alloys using nuclear reaction analysis

摘要

The use of the D(~3He,p)~4He reaction to study the bulk deuterium concentartion in thick Zr alloy targets has been reported previously. In the present paper, we report on new measurements where the technique is extended to larger sample depths using higher projectile energies. This development is important since deuterium is known to concentrate at free surfaces and defects that may occur near surfaces; this effect might yield values unrepresentatively higher than the true bulk concentration. The bulk concentration has been extracted from a detailed comparison of experimental data with simulated proton spectra. In contrast to conclusions reached in an earlier study, the effect of ion beam desorption is unimportant with regard to the measurement of bulk deuterium concentrations when modest ~3He fluences are used. Analyses using beams at energies of 2 and 4.5 MeV are consistent and in good agreement with bulk deuterium concentration measured by high vacuum extraction mass spectrometry (HVEMS).