New model for creep damage analysis and its application to creep crack growth simulations
Additional Document Info
A creep damage model from the micromechanics viewpoint is presented in the paper. In order to mitigate the difficulty of calibrating many parameters in the existing damage evolution models, a simple creep ductility exhaustion approach is employed to account for the accumulation of the creep damage. Two-dimensional and three-dimensional numerical analyses of creep crack growth based on the new creep-damage model and/or Liu-Murakami model are carried out. When the damage parameter reaches a critical value, the load carrying capacity of each damaged element approaches zero and thus crack growth can be characterised by a completely damaged element zone ahead of the initial crack tip. The finite element simulation results obtained are compared favourably with experimental data for the compact tension specimen for 316 stainless steel and bending cracked plate for T91 steel at elevated temperatures. The comparisons show the excellent capability of the proposed model in predicting the crack growth rate and progressive crack profiles. In addition, the influences of the plasticity and mesh size are discussed in this paper. 2014 Institute of Materials, Minerals and Mining.