Clarification of degradation mechanism for yttria-stabilized zirconia due to -ray-induced phase transformation

Okuno, Yasuki

In the accelerator driven system, it is necessary to suppress erosion and corrosion of stainless steel piping by oxygen control of lead bismuth eutectic alloy (LBE). An oxygen sensor using yttria-partially-stabilized zirconia (PSZ) is effective for measuring the oxygen concentration in LBE, and it need to be understood about the influence of radiation during ADS operation. In this study, it was observed that phase transformation from tetragonal to monoclinic crystal occurred when Co -ray was exposed to the PSZ. From the calculation result of the radiation behavior simulation analysis, it has been clarified that this phase transformation was caused by the ionization effect. In this presentation, we report on the phase transformation mechanism of PSZ due to this ionization effect attributed to the radiation.