About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Developments in Advanced Nuclear Structural Materials
|
| Presentation Title |
Microstructural Optimization, High-Temperature Mechanical Properties, and Ion Irradiation Behavior of DED A709 for Nuclear Applications |
| Author(s) |
Subhashish Meher, Asif Mahmud, Robert Seffens, Mark Rhodes, Lin Shao, Isabella J. Van Rooyen |
| On-Site Speaker (Planned) |
Isabella J. Van Rooyen |
| Abstract Scope |
Directed Energy Deposition (DED) of A709 stainless steel offers promise for fabricating large‐scale, complex components for advanced reactor systems, yet as‐built microstructures often exhibit cellular walls with chemical segregation and uneven precipitate distributions that limit high‐temperature performance. In this study, a tailored sequence of solution annealing (1150 °C/1 h) and aging (750°C/10 h) treatments was applied to DED‐deposited A709 to homogenize chemistry and promote strengthening phase precipitation. Post‐heat‐treatment microstructural analysis reveals uniform dispersions of M23C6 carbides as well as a fine distribution of nanoscale MX phases. Tensile testing from ambient to 550°C evaluated yield strength variations across different heat-treated conditions along different directions. Additionally, the Fe2+ ion irradiation response of DED-fabricated A709 was compared with conventional wrought A709. These results demonstrate significant improvement in mechanical properties, with optimized heat treatments eliminating detrimental segregation while promoting beneficial precipitate formation. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, Characterization, Nuclear Materials |