Abstract
Most of models that have been proposed to describe hydrogen embrittlement primarily rely on the interactions between hydrogen and crystalline defects. These interactions are, however, still not fully understood because it is challenging to localize experimentally hydrogen within metallic alloys. Considering that the kinetics of phase transformations and resulting microstructures are mostly controlled by crystalline defects (solute mobility, nucleation barriers, interface energies), we hypothesized that hydrogen should affect the mechanisms of such transformations. Thus, we have experimentally investigated the influence of hydrogen on thermal stability and precipitation in Al-Cu and Al-Zr model alloys. The results provide unique information about interactions between hydrogen and crystalline defects in aluminium alloys.