NUCLEAR-REACTION ANALYSIS OF DEUTERIUM IN DEUTERIDED ZR-2.5 WT-PERCENT NB ALLOY

The deuterium concentration of homogeneous bulk levels in Zr-2. 5 wt% Nb alloy has been measured by nuclear reaction analysis. The accuracy is plus or minus 10% which is comparable to the accuracy of gas analytical techniques. A large surface peak is seen in all the samples due to a deuteride rich layer less than 20 nm thick. The deuterium concentration in this surface layer is more than 10 times the bulk value. At high ion beam fluences, significant effects due to the analyzing beam are seen in the deuterium depth distribution. These are ascribed to deuterium trapping in the **3He implanted region, deuterium diffusion and dissolution of deuterides. These samples are not recommended as general deuterium standards for ion beam analysis experiments because of ion beam effects and the presence of a surface peak. However, they still serve as a useful reference when care is taken to avoid effects due to high fluences.