Numerical study on the creep damage development in circumferential notched specimens under cyclic loading

Numerical calculations with Kachanov-Rabotnov damage law have been performed to study the creep damage development of circumferential notched specimens under cyclic loading. The emphasis was placed on the roles of specimen geometry and loading. The results show that the distributions of creep stress and damage are different under cyclic loading from that under a constant amplitude load. Different specimen has different damage distribution. The development of creep damage in the minimum cross-section varies reasonably with the notch radius. The evolution of creep damage is clearly affected by the mean load, loading cycle (frequency) and ratio. With the other two factors unchanged, each of the following three factors, larger mean load, higher loading frequency and smaller loading ratio, can cause the damage to develop faster.