Oxidation resistance behavior of smart W-Si bulk composites

The oxidation behavior of W-Si bulk composite was investigated to evaluate its performance on the simulating accidental environment in the future fusion reactor. Tungsten trisilicide is the main functional phase, which can form amorphous SiOy and polycrystalline WO3 with nano-porous network during oxidation. This special structure can not only retard W volatilization, but also offer well self-adaption adjustment to different phases. In addition, cracks at the oxide scale/composite interface can be self-healed with the help of this structure. Protrusions are found on the surface of the oxidized W-32Si related with Fe impurity. The vapour-liquid-solid mechanism for the protrusions is proposed.