Nanoindentation experiment and crystal plasticity study on the mechanical behavior of Fe-ion-irradiated A508-3 steel

• Published in: Journal of nuclear materials 2022-12, Vol.571, p.154002, Article 154002
• Main Authors: Lin, Pandong, Nie, Junfeng, Liu, Meidan
• Format: Article
• Language: English
• Subjects: CPFEM; Dislocation loop; Hardness; Irradiation; Nano indentation
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2022.154002

•Irradiation hardness of reactor pressure vessel steel is studied.•The macroscopic deformation behavior of irradiated steel is elucidated.•Mobile/immobile dislocation, absorption dislocation loops contribute to hardening. This study investigates the mechanical properties of A508-3 steel irradiated with Fe ions to 0.1, 0.4, 2.0, and 5.0 dpa at 20, 100, and 300 °C using a nanoindentation experiment and crystal plasticity finite element model (CPFEM). The Nix–Gao model is applied to obtain the hardness H0 based on the measured data. The hardness of the steel increases with increasing radiation damage at all temperatures. The simulations of the nanoindentation process by CPFEM loaded in the [001], [110], [111], [112], and [123] directions concurred with the corresponding experimental data in all the studied cases, validating the CPFEM results. The dislocation loop expedites the increase of mobile dislocation and retards the decrease of immobile dislocation, resulting in larger von Mises stresses of the irradiated samples with a flatter shape, especially near the irradiated region. Furthermore, the area of the von Mises stress shrinks with an increase in temperature. This study could help understand the macroscopic deformation behavior of irradiated steel based on experimental and microstructural analyses.