| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Mechanical Behavior of Nuclear Reactor Materials and Components IV
|
| Presentation Title |
Microstructural Related Mechanical Properties and Fracture Behavior in Nuclear Graphite |
| Author(s) |
Gongyuan Liu, Aman Haque, Jing Du, William Windes, Arvin Cunningham |
| On-Site Speaker (Planned) |
Gongyuan Liu |
| Abstract Scope |
Medium-grain NBG-18 and NBG-17 nuclear graphite are chosen as candidates for the Very High Temperature Reactor (VHTR). The microstructure, characterized by grain sizes up to 1mm and various pores and defects, significantly affects their mechanical and fracture behavior. Mechanical fracture tests combined with X-ray computed tomography (XCT) were performed on both pristine and neutron-irradiated specimens to study crack-microstructure interactions. During fracturing, crack bridging, deflection, and twisting were observed. Micro-CT images from these tests were used to create voxel-based finite element (FE) models with detailed microscale geometry that holds the potential to predict crack initiation and propagation. Raman spectroscopy revealed localized residual stresses on the notch surface, indicating that sample preparation-induced stresses might affect crack initiation predictions. Nanoindentation was conducted on both pristine and neutron-irradiated specimens. The elastic modulus and hardness of pristine and irradiated specimens were compared. The indentation results could serve for further FE simulation of neutron-irradiated specimens. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, |