|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Accelerated Materials Evaluation for Nuclear Application Utilizing Test Reactors, Ion Beam Facilities and Integrated Modeling
||Effect of Temperature and Helium on Microstructure Evolution in Dual Ion Irradiated HT9 Steel
||David Woodley, Zhijie Jiao, Kai Sun, Gary S Was
|On-Site Speaker (Planned)
Ferritic-martensitic steels are leading candidates for structural materials in next generation reactors due to their resistance to swelling. The process of cavity nucleation and growth is not well understood but is known to be influenced by temperature, other microstructural features and helium generation from transmutation reactions. Dual ion irradiations were performed at the Michigan Ion Beam Laboratory on alloy HT9. A defocused 5 MeV Fe<sup>++</sup> beam and a degraded ~2 MeV He<sup>++</sup> beam were used for irradiations to a damage level of 188 dpa at temperatures from 440-480<sup>o</sup>C with helium-to-dpa ratios from 0 to 0.2 appm He/dpa. The effects of temperature and helium-to-dpa ratio on cavity, precipitate and dislocation loop evolution were analyzed. Increasing temperature resulted in an increased diameter and a decreased density for all features. Increasing helium-to-dpa ratio was found to increase diameter and decrease density for cavities and have negligible effect on the other microstructure features.
||Planned: Supplemental Proceedings volume