Microstructure Evolution and Mechanical Response of Nanolaminate Composites Irradiated with Helium at Elevated Temperatures

We summarize recent work on helium ( He) interaction with various hetero-phase boundaries under high temperature irradiation. We categorize the ion-affected material beneath the He-implanted surface into three regions of depth, based on the He/vacancy ratio. The differing defect structures in these three regions lead to the distinct temperature sensitivity of He-induced microstructure evolution. The effect of He bubbles or voids on material mechanical performance is explored. Overall design guidelines for developing materials where He-induced damage can be mitigated in materials are discussed.