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DOE OSTI · 2998562

Interpretation of Ion Irradiation and Neutron Irradiation Damage in Additively Manufactured 316 Stainless Steel using Multiscale Modeling

Kadambi, Sourabh Bhagwan [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000160851817)·Swisher, Mathew M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]·Mazumder, Sanjoy Kumar [Idaho National Laboratory (INL), Idaho Falls, ID (United States)]·Yorgason, William Tanner [Arizona State Univ., Tempe, AZ (United States)]·Jokisaari, Andrea M. [Aalo Atomics, Austin, TX (United States)]
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Abstract

The accelerated adoption of nuclear energy necessitates advanced manufacturing technologies, such as additive manufacturing, to meet heightened supply chain requirements and support innovative reactor technologies. Due to the unique microstructural characteristics of additively manufactured materials under distinct solidification conditions, comprehensive evaluation of their performance in reactor environments is essential. The Advanced Materials and Manufacturing Technologies program under the Department of Energy's Office of Nuclear Energy focuses on understanding the irradiation performance and damage evolution of laser powder bed fusion 316 stainless steel, with an emphasis on integrating ion and neutron irradiation data to accelerate the development and qualification of materials for advanced nuclear reactor applications. While ion irradiation is a cost- and time-effective method, modeling and simulation are required to interpret the data for the broader range of irradiation conditions encountered in advanced reactors. In fiscal year 2025, integrated multiscale modeling and simulations were conducted to assess irradiation damage in additively manufactured 316 stainless steel. Key outcomes include predictions of chromium enrichment at grain boundaries, nickel enrichment at dislocation cell walls and void surfaces, and heterogeneous void evolution under ion and neutron irradiation conditions. Cluster dynamics simulations revealed the coarsening of voids at high irradiation temperatures and the suppression of void growth by high network dislocation density, while also demonstrating significant growth and coarsening of voids and self-interstitial atom loops at low dose rates. Machine learning-accelerated atomistic simulations highlighted the impact of the local environment and chromium concentration on vacancy diffusivity, providing key insights on the influence of composition on void swelling and radiation-induced segregation. Additionally, molecular dynamics simulations demonstrated the presence of defect production bias and a significant effect of carbon content on defect cluster behavior. These combined efforts aim to predict the performance of additively manufactured materials under various reactor conditions, supporting their qualification for nuclear reactor applications by interpreting ion irradiation data. This report underscores the potential of integrated multiscale modeling to analyze ion irradiation data in the effort to accelerate the qualification of additively manufactured materials for nuclear reactor components.

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316 stainless steel36 MATERIALS SCIENCEadditive manufacturingcluster dynamicsdensity functional theorykinetic Monte Carlomachine learningmolecular dynamicsphase field

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Kadambi, Sourabh Bhagwan [Idaho National Laboratory (INL), Idaho Falls, ID (United States)] (ORCID:0000000160851817), Swisher, Mathew M. [Idaho National Laboratory (INL), Idaho Falls, ID (United States)], Mazumder, Sanjoy Kumar [Idaho National Laboratory (INL), Idaho Falls, ID (United States)], Yorgason, William Tanner [Arizona State Univ., Tempe, AZ (United States)], Jokisaari, Andrea M. [Aalo Atomics, Austin, TX (United States)]. 2025-09-30. Interpretation of Ion Irradiation and Neutron Irradiation Damage in Additively Manufactured 316 Stainless Steel using Multiscale Modeling. https://doi.org/10.2172/2998562

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