Study on eutectic melting behavior of control rod materials in core disruptive accidents of sodium-cooled fast reactors, 3; Kinetic study of boron carbide-stainless steel eutectic melting by differential thermal analysis

Kikuchi, Shin  ; Yamano, Hidemasa   ; Nakamura, Kinya*

In a postulated severe accidental condition of sodium-cooled fast reactor (SFR), eutectic melting between boron carbide (BC) and stainless steel (SS) may take place. Thus, kinetic behavior of BC-SS eutectic melting is one of the important phenomena to be considered when evaluating the core disruptive accidents in SFR. In this study, for the first step to obtain the fundamental information on kinetic feature of BC-SS eutectic melting, the thermal analysis using the pellet type samples of BC and Type 316L SS as different experimental technique was performed. The differential thermal analysis endothermic peaks for the BC-SS eutectic melting appeared from 1483K to 1534K and systematically shifted to higher temperatures when increasing heating rate. Based on this kinetic feature, apparent activation energy and pre-exponential factor for the BC-SS eutectic melting were determined by Kissinger method. It was found that the kinetic parameters obtained by thermal analysis were comparable to the literature values.