[3C06-09] Cladding Coating

[3C07] Study on coating technic to enhance accident tolerance of fuel cladding

(2) Oxidation and hydriding behavior of the Cr coated Zry4

*Keito Kawai¹, Yosiyuki Nemoto², Shinichiro Yamasita², Yasuhiro Ishijima², Ikuo Ioka², Koudai Funamoto³, Hisao Atsumi¹ (1. Kindai Univ., 2. JAEA, 3. Tocalo)

Keywords:light-water reactor, safety improvement, accident tolerance, fuel cladding

As a candidate for accident tolerant fuel (ATF) cladding tubes, chromium (Cr) coated tubes are being developed. The Cr coating on the outer surface is expected to improve oxidation resistance in high-temperature steam compared to conventional zirconium alloy cladding tubes. However, when considering the case of a loss-of-coolant accident (LOCA) and subsequent cladding tube rupture, it is necessary to also consider oxidation and hydrogen absorption on the inner surface of the cladding tube. In this study, after oxidation tests in high-temperature steam using a thermogravimetry (TG) apparatus, cross-sectional observations of the samples and measurements of hydrogen absorption were performed. In the lecture, we will discuss the results of these experiments.