Three-Dimensional Imaging of Radiation-Induced Defects in Metals

The formation of nanoscale void and gas bubble superlattices in metals and alloys under radiation environments has been proposed as a way to mitigate radiation-induced damage such as swelling and to develop next-generation radiation tolerant materials. However, the microstructural changes and strain induced by such superlattices are not well understood. In our approach, we utilize multi-reflection Bragg coherent diffraction imaging (MBCDI) to quantify the full strain tensor induced by void superlattices in iron (Fe) irradiated chromium substrate, a model metallic system. The combination of MBCDI with static mechanics simulations provides a powerful method for detailed investigation of the strain and structural changes caused by radiation-induced defects during Fe ion implantation that is previously inaccessible via conventional techniques. Our approach provides a quantitative estimation of strain generated at a microscopic level and helps predict the number density of defects with a high degree of accuracy.