Effects of alloying elements on the tensile properties and oxidation behavior of modified Zircaloy-4 in 360°C water

The effects of oxygen and tin contents on the tensile properties and oxidation behavior of modified Zircaloy-4 (Zry-4) were investigated. The modified alloys were prepared by changing the chemical compositions of Zry-4; the tin contents were decreased from 1.0 wt% to zero while oxygen increased from 0.1 to 0.8 wt%, 0.1 wt% Nb was added and the amounts of Fe and Cr were kept 0.1 and 0.2 wt%, respectively. The UTS increased significantly with the oxygen content. 0.2 wt% oxygen could compensate the decrease in strength resulted from the reduction of tin content from 1.0 wt% to zero. The weight gain in water at 360°C under a pressure of 180 bar increased with tin and oxygen contents. The alloy with tin and oxygen contents of zero and 0.1 wt% showed the lowest weight gain for 120 days of oxidation test.