Microstructural evolution of NF709 austenitic stainless steel under in-situ ion irradiations at room temperature, 300, 400, 500 and 600 °C

Journal Article · 01 October 2018 · Journal of Nuclear Materials

DOI: https://doi.org/10.1016/j.jnucmat.2018.07.044 · OSTI ID:1490233

Xu, Chi ^[1]; Chen, Wei-Ying ^[2]; Chen, Yiren ^[2]; Yang, Yong ^[3]

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1. Univ. of Florida, Gainesville, FL (United States); Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division
2. Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division
3. Univ. of Florida, Gainesville, FL (United States)

Irradiation induced microstructural changes in the NF709 austenitic stainless steel were investigated under 1 MeV Kr ion irradiations to a dose of 3 dpa at room temperature (RT), 300, 400, 500 and 600 °C, and a dose of 20 dpa at RT. The irradiation-induced defects and the stability of precipitates were characterized with transmission electron microscopy (TEM). Frank dislocation loops were observed in all the irradiated samples, and the loop sizes were much larger at 600 °C than those at lower temperatures. “Raft” defect structures, formed through self-alignment of small dislocation loops, were also observed in all irradiated samples. M23C6 precipitates were amorphorized under irradiations at RT and 300 °C, but remained to be crystalline at 400 °C and above. MX precipitates were stable under irradiations at RT up to 20 dpa, and at temperatures below 600 °C to 3 dpa. At 600 °C, some MX precipitates were observed to dissolve during in-situ irradiation, suggesting possible precipitate instability at this irradiation temperature.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Nuclear Energy (NE); USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-06CH11357; AC07-051D14517
• OSTI ID: 1490233
• Alternate ID(s): OSTI ID: 1582079
• Journal Information: Journal of Nuclear Materials, Vol. 509; ISSN 0022-3115
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English