TMAP modeling of D release from baked multi-layer Be-D co-deposits

Single-layer Beryllium-Deuterium (Be-D) co-deposits were analyzed using Thermal Desorption mass Spectrometry (TDS) as outlined in the companion paper (Baldwin et al 2019 Phys. Scr. PFMC Proc.). This work details the TMAP modeling and the analysis of selected samples that received double-layer (DL) coatings to study co-deposit thickness and prior bake effects. TDS data were simulated with detrap energies 0.8, 0.9, and 1.0 eV. In DLs formed at 393 K, modeling revealed that under-layers baked at 623 K for either 2 or 20 h had little pumping effect on over-layers, suggesting empty trap removal during bake. Extrapolated to ITER, data and analysis suggest less impact on the ongoing ITER bake efficiency than previously predicted (Baldwin and Doerner 2015 J. Nucl. Mater. 467 38391).