Athermal swelling and creep of heavily irradiated iron under uniaxial stress

L Stefanescu and M Boleininger and PW Ma, PHYSICAL REVIEW MATERIALS, 7, 073604 (2023).

DOI: 10.1103/PhysRevMaterials.7.073604

The athermal irradiation-induced swelling and creep in iron under the influence of external uniaxial stress were investigated through atomic scale simulations using the creation-relaxation algorithm. The defect relaxation volume density tensors (or eigenstrains) were evaluated as a function of external uniaxial stress. When the dose exceeded the level at which isolated defects were formed, interstitial-type defect clusters were formed with polarization, resulting in crystal growth in the direction where tensile stress was applied, and growth in the other two perpendicular directions when compressive stress was applied. The concentration of vacancies, isolated self-interstitial atoms, Laves phases clusters, and dislocations in the microstructure were largely unaffected by external stress up to +/- 1 GPa. Biased crystal growth was primarily attributed to the anisotropic formation of new lattice planes through the coalescence of interstitial defect clusters, leading to plastic deformation depending on the direction and magnitude of the external stress.

Return to Publications page