Non-destructive characterization of films grown on Zircaloy-2 by annealing in air

Zircaloy-2 is often used in engineering applications because of its corrosion resistance; a property attributable to a protective oxide film that grows on its surface. Variable angle infrared (IR) reflection spectroscopy and atomic force microscopy are used to determine the thickness and roughness of such films grown thermally on Zircaloy-2 surfaces in air. We find cubic growth kinetics in the temperature range 500-600 deg. C with an apparent activation energy of 227 kJ mol-1. We also demonstrate how an increase in microscopic surface roughness at higher temperatures correlates with a loss of oxide homogeneity as sampled by the IR method. (author)