Development of laser heating facility for steam oxidation at extreme temperatures

倉田 正輝 ; Pham, V. H.   ; 永江 勇二 

Kurata, Masaki; Pham, V. H.; Nagae, Yuji

Since the disaster at Fukushima Daiichi Nuclear Power Plant, development of accident tolerant fuel to manage severe accidents has been proposed. As temperature of fuel rods could reach to temperatures above 2000C during the accident, investigation of oxidation behavior at such temperatures for fuel claddings must be conducted. Nevertheless, there is no test facility capable for operating at such conditions. In this study, we developed a laser heating facility for steam oxidation of cladding materials at extreme temperatures. Main features of the facility are controlled environment, in situ observation, extreme fast heating and cooling rate and off gas analysis. As the heat is focused on the test sample only, the facility can be operated at temperatures above 2000C. Preliminary tests have been conducted for monolithic SiC at 1400-1800C for 1-7 h under 0.96 atm steam partial pressure. Results of the investigation showed that SiC underwent a mass loss which obeyed paralinear laws. Based on the mass change data, parabolic oxidation rate and linear volatilization rate of the process were obtained. The apparent activation energy of the oxidation process was calculated to be 96 kJmol . Bubbling phenomenon was observed on SiC sample surface at 1800C.