On the study of the effects of notch shape on the creep damage under cyclic loading

Numerical calculations with the K-R damage law have been performed to study the creep damage development of different notch specimens (Circumferential, U-type and V-type notch) under cyclic loading. Emphasis was placed on the roles of notch geometry, multi-axial stress rupture parameter cx, frequency and stress ratio. Notch shape has a notable influence on the creep damage and fatigue life. Different notch specimens have different creep damage distributions. The development of creep damage in the minimum cross-section varies with notch shape and notch radius. For the Circumferential notch specimen, the maximum creep damage lies at the point in from notch tip; For the U-type and V-type notch specimens, the maximum creep damage always happens at the notch tip. Creep damage is greatly affected by the amplitude of load, stress ratio, multi-axial stress rupture parameter alpha. Larger mean stress, stress ratio and material parameter 7 cause faster development of the creep damage. (c) 2006 Elsevier Ltd. All rights reserved.