Work

The interaction of edge dislocations with hydrogen-helium bubbles in tungsten

Year: 2025

Type: article

Abstract: In fusion reactors, plasmas-facing components undergo degradation due to displacement damage and injection of gas impurities. Significant amounts of hydrogen (H) and helium (He) impurities can be introduced into materials through plasma exposure and nuclear transmutation, and their synergistic effects lead to the formation of mixed He/H bubbles under irradiation, changing their hardening mechanisms. In this study, molecular dynamics (MD) models were developed to study the interaction between ½<111> edge dislocations with mixed He/H-bubbles in W. The critical resolved shear stress (CRSS) that is required for dislocation breakaway increases with He/H-to-vacancy ratio at 600 K, indicating strong pinning effects of mixed He/H bubbles. However, as the temperature increases up to 1400 K, the mixed He/H bubbles become unstable as the H atoms are increasingly emitted from the mixed He/H bubbles and migrate into W matrix, which lowers bubble pressure and CRSS. Overall, these results highlight the synergistic effects of He and H on dislocation behavior in irradiated W during deformation.

Source: Journal of Nuclear Materials

DOI: 10.1016/j.jnucmat.2025.156362

Authors: Safqut Sanwar, Mathew M. Swisher, Cheng Sun

Institutions: Clemson University, Idaho National Laboratory

Language: English

Topic: Fusion materials and technologies

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $2,640

Funders: U.S. Department of Energy, U.S. Nuclear Regulatory Commission, Idaho National Laboratory