Creep behaviour of U–6%Zr alloy by impression creep technique

In this study, the impression creep behaviour of U–6 wt.%Zr alloy was studied in the temperature range 550–650 °C at different stresses. The velocity of the punch at different stresses and temperatures was evaluated for the above alloy. The creep curves at 575 °C showed a wavy phenomenon at all stresses. The stress exponents and thermal activation parameters of the above alloy were determined. A power law behaviour is displayed in the temperature range 600–650 °C with the stress exponents range from 8 to 8.4. The activation enthalpy for the U–6%Zr alloy was found to be independent of stress with an average value of 157 kJ/mol.

► The creep behaviour of U–6%Zr alloy studied using impression creep technique in temperature range of 550–650 °C. ► The creep curves at 575 °C showed a wavy phenomenon due to the formation of δ phase. ► The stress exponents in temperature range of 600–650 °C range from 8 to 8.4. ► The activation enthalpy for U–6%Zr was found to be 157 ± 4 kJ/mol. ► The concept of structure invariant model is used to interpret deformation mechanism.