The behaviors of static and cyclic creep of Ni-35Cu alloy are investigated at 485K (0.43 Tm) and 450 MPa. The effect of stress amplitude on the cyclic creep behavior is studied by measuring the friction stress and the activation energy for the creep.
Cyclic creep acceleration is observed and the cyclic creep rate increases with the stress amplitude. The activation energy for cyclic creep is slightly lower than that for static creep and the activation energy for cyclic creep deformation is slightly decreasing with increasing stress amplitude.
In the cyclic creep deformation, the fact that the activation Energy is not significantly affected by the stress amplitude means the deformation mechanism is independent of the stress amplitude.
From the above results, it is considered that the cyclic creep rate is controlled by the friction stress level and the recovery rate during unloading.
