Impact of surfacic oxide layer on the kinetics of He bubbles growth in W(110)

Irradiation of the first wall tungsten (W) materials by He is a crucial parameter to consider for the application of nuclear fusion to energy production, with one major consequence being the modification of the crystalline structure. The aim of this proposal is to address the formation and growth of He bubbles under the W surface; in order to get closer to tokamaks operating conditions we must address the presence of oxides on the W surfaces. In particular, the impact of a surfacic oxide layer could modify the He bubbles depth distribution and favour their formation at the oxide/metal interface. The oxide

could also impact the surface bursting process that was observed on non-oxidized W crystal. It would therefore be of the utmost interest to study He irradiation on W with oxide layers, and measure via GISAXS and GIXD the impact on the bubble growth kinetics, spatial distribution, faceting during annealing up to 1400°C as well as strain evolution.