About this Abstract |
| Meeting |
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Symposium
|
Materials in Nuclear Energy Systems (MiNES) 2025
|
| Presentation Title |
Creep Damage Quantification in LPBF Ni-Based Alloys Using Non-Destructive Evaluation and Advanced Microstructure Characterization |
| Author(s) |
Sebastien Dryepondt, Holden Hyer, Amanda Heimbrook, Rahul Franklin, Amir Ziabari, Yi-Feng Su, Chase Joslin |
| On-Site Speaker (Planned) |
Sebastien Dryepondt |
| Abstract Scope |
The advanced materials and manufacturing technologies (AMMT) program aims at accelerating the integration of new materials and manufacturing technologies such as laser powder bed fusion (LPBF) into nuclear-related systems. Ni-based alloys offer superior strength and corrosion resistance compared to advanced austenitic steels and creep testing was performed at 725-750°C on 𝛄’ strengthened LPBF 282 and solution strengthened LPBF 625. X-ray computed tomography and advanced microstructural image analysis were utilized to characterize defects evolution during creep testing. A few large printing flaws were directly linked to the LPBF 282 failure, and creep-related cracks either initiated from printing defects or formed and propagated along grain boundaries. The standard 4h at 800°C aging treatment resulted in the formation of a high number density of 𝛄’ strengthening precipitates, but solution annealing at 1180°C for 1h was not sufficient to fully recrystallize the alloy. Both the printing defects and grain structure played a role in the lower creep performance of the LPBF 282 compared to wrought 282. The LPBF 625 alloy was nearly defect-free, leading to creep strength similar to the creep strength of wrought 625. Annealing at 1150°C for 1h resulted in the recrystallization of the alloy and isotropic tensile properties, but an increase in creep rate was observed at 725°C. Interrupted creep testing was conducted in vacuum on a polished and etched specimen to quantify creep damages such as grain boundary cavitation and dislocation density evolution. Integration of these results into creep lifetime modelling and material qualification approaches will be discussed. |
| Proceedings Inclusion? |
Undecided |