Pre-oxidation effect of a zirconium-silicide sputtered surface on boiling performance and oxidation resistance

Thin zirconium silicide (ZrSi2) material was coated on present cladding substrate, Zircaloy-4. At 700 °C air environment, the ZrSi2 coating prevented thermal oxidation and thereby protected the underlying Zircaloy-4 substrate. To investigate the boiling characteristics, the pool boiling experiment with saturated water and Leidenfrost experiment with low weber number were examined under atmospheric pressure condition. The experimental results showed that by thermal oxidation, critical heat flux and Leidenfrost temperature were not changed on ZrSi2 coated surface whereas the results were changed on uncoated Zircaloy-4 substrate. The surface parameters were changed while oxidation process and led to the transition of boiling parameters.