Santanu Ghosh
Indian Institute of Technology Delhi, India
Title: Radiation Stability of Nanostructured Ytrium Stabilized Zirconia
Biography
Biography: Santanu Ghosh
Abstract
Radiation damage in materials is strongly influenced by specific energy loss (electronic energy loss (Se) and/or nuclear energy loss (Sn)), material microstructure (grain size) and environmental (irradiation) temperature.For a systematic understanding of the dependence of radiation tolerance on these factors, yttria stabilized zirconia (YSZ) with different grain sizes (tens of nano-meters to few microns) were irradiated under different conditions (single beam irradiation with high energy (Se>>Sn) ions at 300K and 1000K, single beam irradiation with low energy (Sn>>Se) ions at 300K & simultaneous dual beam irradiation with high and low energyions at 300K).The low and high energy ions were chosen to mimic the damage produced by alpha recoils and fission fragments respectively, and thus the irradiations at 1000K and the dual beam irradiations helped to better simulate typical nuclear reactor environment. For the high energy (single beam)irradiations, (i) the nano-crystalline samples were more damaged compared to the micro-crystalline sample irrespective of the irradiation temperature and (ii) the damage for all grain sizes was found to be reduced at 1000K compared to that at 300K.Interestingly,this damage reduction was significantly more for the nano-crystalline samples as compared to the microcrystalline one.Results are explained in the framework of thermal spike model.