Creep Behaviour of a Zr-1 wt% Nb Alloy at Elevated Temperatures

This paper presents experimental data regarding creep behaviour of a Zr-1 wt% Nb alloy at elevated (623 K) and at high temperatures (873-1123 K) corresponding to loss-of-cooling situation of fuel cladding tubes for nuclear reactors. For an elaboration of methodological procedure and comparison purposes, the tensile creep tests were conducted using both constant stress and constant load over a wide range of applied stress. The substantial differences in the acquired creep data between constant stress and constant load creep testing were found especially at high stresses and large creep strain levels.