|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Accelerated Materials Evaluation for Nuclear Applications Utilizing Irradiation and Integrated Modeling
||Effective Defect Sinks in Metallic Composite with Nanodispersoids: In situ Ion Radiation Transmission Electron Microscopy and Position Annihilation Lifetime Spectroscopy
||Kangpyo So, Ming Liu, Mohammad Shahin, Myles Stapelberg, So Yeon Kim, Michael Short, Ju Li
|On-Site Speaker (Planned)
The accumulation of defects during irradiation leads to material property degradation modes such as embrittlement and swelling, eventually causing material failure. Effective and efficient removal of defects is of crucial importance to design radiation damage-tolerant materials. Here, by biasing defect migration pathways via carbon nanotube (CNT) infiltration, we present a greatly enhanced damage-tolerant metal-CNT composite with defect storage measured to be one order of magnitude lower than that in pure, irradiated Al. In situ ion irradiation transmission electron microscopy (TEM) experiments and atomistic simulations together reveal the dynamic evolution and convergent diffusion of radiation-induced defects to CNTs, facilitating defect recombination and enhancing radiation tolerance. The occurrence of CNT-biased defect convergent migration is tuned by the thermodynamic driving force of the stress gradient in the Al matrix due to the CNT phase transformation. Further positron annihilation lifetime spectroscopy of nano-dispersion will be discussed to verify the defect annihilation mechanism.