J. Mater. Sci. Technol. ›› 2026, Vol. 244: 180-185.DOI: 10.1016/j.jmst.2025.04.025

• Research Article • Previous Articles     Next Articles

Effect of proton irradiation on ferrite microstructure in aged 308L stainless steel

Xiaofeng Yanga, Yuanfei Lib, Jianchao Penga,c, Xue Liangc, Wenqing Liua,*, Xiangbing Liub,*, Hefei Huangd,*   

  1. aInstitute of Materials, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China;
    bSuzhou Nuclear Power Research Institute, Suzhou 215004, China;
    cKey Laboratory of Microstructure, Shanghai University, Shanghai 200444, China;
    dNational Key Laboratory of Thorium Energy, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
  • Received:2024-12-03 Revised:2025-04-22 Accepted:2025-04-29 Published:2026-02-10 Online:2025-05-26
  • Contact: *E-mail addresses: wqliu@staff.shu.edu.cn (W. Liu), liuxbing@cgnpc.com.cn (X. Liu), huanghefei@sinap.ac.cn (H. Huang)

Abstract: To investigate the microscopic changes in the ferrite phase of the 308 L stainless steel matrix under service conditions, the welding material was first aged at 400 °C for 5000 h, followed by 240 keV proton irradiation at the same temperature. Transmission electron microscopy (TEM) and atom probe tomography (APT) were used to characterize the ferrite phase as a function of irradiation damage and depth. The results indicate that, after thermal aging, the G phase forms within the ferrite phase and spinodal decomposition occurs simultaneously. Irradiation leads to an increase in the size of the G phase and the formation of NiSi clusters due to irradiation-induced segregation. The size and number density of NiSi clusters increase with increasing irradiation dose. However, no significant changes in the degree of spinodal decomposition are observed.

Key words: Proton irradiation, Thermal aging, 308 L stainless steel, Atom probe tomography, Spinodal decomposition, G phase