In-core ECP sensor designed for the IASCC experiments at JMTR

Tsukada, Takashi ; Miwa, Yukio; Ugachi, Hirokazu ; Matsui, Yoshinori ; Itabashi, Yukio; Nagata, Nobuaki*; Dozaki, Koji*

IASCC initiation and propagation tests will be performed on the per-irradiated specimen in the Japan Materials Testing Reactor (JMTR). Since in core, the radiolysis of water causes a generation of various kind of radical species and some oxidizing species such as hydrogen peroxide, the water chemistry in irradiation capsules must be assessed by measurements of the electrochemical corrosion potential (ECP). For the in-core measurement of ECP in JMTR, we fabricated and tested the Fe/FeO type ECP sensor. After the fabrication, the function of each sensor was examined in high temperature water by out-of-core thermal cycling and high temperature holding tests.