| About this Abstract |
| Meeting |
Materials Science & Technology 2020
|
| Symposium
|
Advanced Characterization of Materials for Nuclear, Radiation, and Extreme Environments
|
| Presentation Title |
In Situ Observation of Irradiation Damage in Polycrystalline Nuclear Graphite |
| Author(s) |
Dong (Lilly) Liu, David Cherns, Joshua Kane, Weiying Chen, Steve Jones, Karthik Chinnathambi, William Windes |
| On-Site Speaker (Planned) |
Dong (Lilly) Liu |
| Abstract Scope |
Understanding irradiation induced damage in nuclear graphite is of particular relevance to operating AGRs and some GenIV designs. Ex situ C+ implantation (Surrey Ion Beam Centre, UK) and in situ Ar+ irradiation (IVEM, ANL, USA) were used to simulate neutron damage over a range of temperatures up to 1000C. The surface morphological changes as well as residual stresses introduced by carbon ions were characterized and the decrease in crystallite size was compared to samples with the same neutron doses. It was found that large amount of porosity was introduced due to irradiation which has subsequently contributed to the volume change. The Ar+ irradiation carried out in situ within a TEM showed that basal plane dislocation movement was the primary cause of the macro-scale behavior. A novel mechanistic model was proposed based on these observations and it is considered to be applicable to all materials with nano-scale 2D graphite-like polycrystalline structures. |