Optical properties of Zircaloy and Zircaloy oxide by ellipsometry

The optical constants of Zircaloy 2 and 4, which are alloys of zirconium and their thermal oxides, are determined by ellipsometry over a 0.3131-3.39-microm wavelength range. Both the refractive index and extinction coefficient of both types of Zircaloy are similar to those of zirconium. Both components of the complex index increase with wavelength from nominal values of 1.135-il.523 at 0.3131 microm to 4.846-i7.345 at 3.39 microm. The refractive indices of the oxide of Zircaloy 2 and 4 heated in air are similar to that of zirconium oxide and decrease in value as a function of wavelength from ~2.3 at 0.3131 microm to ~2.0 at 3.39 microm. The extinction coefficient is both thickness and temperature dependent and varies between ~0.1 and 0.3.