Finite element simulation of creep-fatigue crack growth behavior for P91 steel at 625°C considering creep-fatigue interaction

• Published in: International journal of fatigue Vol. 98; pp. 41 - 52
• Main Authors: Jing, Hongyang, Su, Dingbang, Xu, Lianyong, Zhao, Lei, Han, Yongdian, Sun, Ruiwen
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2017; Elsevier BV
• Subjects: Computer simulation; Continuum damage mechanics; Crack propagation; Cracks; Creep-fatigue interaction; Damage accumulation; Experiments; Fatigue failure; Finite element method; Finite element simulation; Fracture mechanics; Materials fatigue; Mathematical models; Metal fatigue; Metals creep; Numerical analysis; P91 steel; Creep-fatigue interaction; Damage accumulation; Finite element simulation; P91 steel
• ISSN: 0142-1123; 1879-3452
• DOI: 10.1016/j.ijfatigue.2017.01.004

•A creep-fatigue damage evolution model is proposed.•A third term is used to consider the creep-fatigue interaction.•The model is proved to have the ability in predicting creep-fatigue crack growth.•The effects of initial crack depth, specimen dimension and hold time are studied. A creep-fatigue crack growth model considering creep-fatigue interactions based on continuum damage mechanics was proposed in this paper. Numerical analyses of creep-fatigue crack growth of P91 steel at 625°C using compact specimens were conducted. The results agreed well with the experiment which indicated its good capability in predicting creep-fatigue crack growth behavior. The effects of initial crack depth, specimen dimension and hold time on crack growth behavior were investigated using the model. The results indicated that the increasing initial crack depth and specimen dimension promoted the crack growth rate, while the decreasing hold time accelerated the crack growth.