Thermophysical Properties of Zirconium Alloy E110 (Zr-0.01Nb) after Oxidation in Air Atmosphere

Zirconium alloys are used in nuclear power engineering as a cladding for the fuel elements and other parts of nuclear reactors. Reliable data on thermophysical properties of these alloys are necessary to predict the behavior of the fuel elements both at normal operation and at design basis accidents. At the accident conditions, when the reactor may lose coolant, the destructive influence of high temperatures and oxidized ambient atmosphere have an effect on the cladding. The subsecond resistive pulse heating technique has been used to study the temperature dependence of the heat capacity and spectral emissivity (for the wavelength of 0.65 mu m) of the zirconium alloy E110 (Zr-O.O1Nb) after oxidation in air atmosphere. The tubular samples were oxidized at multiple pulse heating cycles up to different maximum temperatures (1200, 1300, 1400, 1500, and 1600 K) and subsequent cooling. It is shown that the thermophysical properties of the oxidized samples depend on the maximum temperature of oxidation.