Temperature threshold for preferential bubble formation on grain boundaries in tungsten under in-situ helium irradiation

• DOI: 10.1016/j.scriptamat.2020.01.013
• Publication Date: 2020-01-27T10:51:51Z
• Authors: O. El-Atwani; W.S. Cunningham; D. Perez; E. Martinez; J.R. Trelewicz; M. Li; S.A. Maloy
• Keywords: Liquid bubble; radiation damage

Abstract Understanding a material's radiation tolerance requires examining its performance under different irradiation conditions. Here, we investigate the radiation tolerance in terms of helium bubble damage in tungsten irradiated in-situ with 16 keV helium at 1073 K and 1223 K. Damage evolution represented by helium bubble density, size and total change in volume in the grain matrices and the grain boundaries are quantified as a function of fluence. Preferential large bubble formation and a higher change in volume on the grain boundaries occurred at 1223 K, suggesting faster migration of certain helium-vacancy complexes as confirmed by a diffusion-reaction model.