Oxidation and evaporation behaviors of Mo under a severe accident condition

Liu, J.  ; Nakajima, Kunihisa  ; Miwa, Shuhei  ; Karasawa, Hidetoshi; Osaka, Masahiko  

To construct a precise Mo release model in a severe accident, oxidation and evaporation behaviors of metallic Mo powders were investigated by the thermogravimetric analysis technique. The experimental results showed that there were two evident oxygen concentration gradients on the diffusion path of O(g) to surface of powders and in the solid MoO layer formed on the surface of Mo powders, respectively. Therefore, the oxidation and evaporation rates of Mo were thought to be influenced by oxygen diffusion rates in the gas phase and the solid MoO layer.