Study on irradiation effects on component materials of electrochemical corrosion potential sensors

Chimi, Yasuhiro; Hanawa, Satoshi ; Nishiyama, Yutaka ; Nakamura, Takehiko ; Tahara, Yuki*; Kojima, Takao*; Inoue, Hiroyuki*; Iwase, Akihiro*

In order to understand irradiation effects on measurement of electrochemical corrosion potential (ECP), we have investigated the irradiation effects on component materials of zirconia membrane type ECP sensors. In the present report, we will present the change in properties of yttria(YO)-stabilized zirconia(ZrO) (YSZ), which is used as the membrane, irradiated with energetic heavy ions. After irradiation with 200-MeV Xe ions up to 110 ions/cm at room temperature, the lattice parameter of YSZ specimens increases beyond about 0.5% of initial value. Micro-Vickers hardness of the specimens also increases with ion fluence. Considering the damage in YSZ by Xe-ion irradiation (about 0.2 dpa maximum), in case of in-core use of zirconia membrane type ECP sensors, neutron irradiation can affect the durability of a junction between YSZ and metal housing in the sensors.