Study on creep response of nickel-base single crystal circular notched specimens

Seven U-type and V-type circular notched specimens of nickel-base single crystal DD3 had been creep numerical simulated under tensile orientation [001] and 950°C with the software MARC. These finite element models are capable of representing complex stress state. The durability lifetimes including circular notch and smooth specimens were investigated based on the maximum shear stress amplitude. The results show that the notch size has strong influence on stress distributions and lifetime. The resolved shear stresses increase with the increasing of notch radii. For the same net-section stress, the notched specimens have a longer lifetime than the smooth specimen. This result confirms to P. Lukas' research.