Phase-field modeling of high cyclic fatigue in brittle materials

Abstract

The engineering structures are designed to operate in an elastic domain, and the plastic deformations are not permissible. Therefore, the safety of structures can be violated if the structure is subjected to cyclic loading conditions due to the accumulation of damage in the material. The damage of the material is usually considered as the appearance of micro-cracks and dislocation. These phenomena can be modeled by the Phase-Field Damage Modeling (PFDM) approach. The PFDM in brittle materials considers the elastic strain energy the main and the only source of material damage. By introducing the fatigue degradation function, the PFDM can be extended to predict the structure's fatigue under cyclic loading-unloading conditions. The PFDM framework is implemented into Finite Element Software, and the first simulation results on one element example are presented. The results show good qualitative simulation results, which follow the phenomenology of structures' behavior under cyclic loading and fatigue conditions.