Analysis of the multiaxial stress state during crack initiation by the fracture phase field method

• Applicant: Professor Dr.-Ing. Ralf Müller
• Subject Area: Computer-Aided Design of Materials and Simulation of Materials Behaviour from Atomic to Microscopic Scale ; Mechanics
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 523648868

FGA or WEA/WEC occur in the presence of non-metallic inclusions and the associated complex multiaxial stress states, which are also present in rolling contact situations. FGA and WEC/WEA are closely related to material failure by cracks in the high cycle fatigue. The interrelation between cracks and microstructural changes is not well understood. The project aims at clarifying this question by means of simulations. To compute crack initiation and crack propagation in complex stress states a fracture phase field is used. The fracture phase field introduces an order parameter that interpolates continuously between fractured and virgin material. The evolution of the order parameter is given by an evolution law. For the modeling of cyclic crack propagation a variational approach is combined with a cyclic damage formulation.

• DFG Programme: Research Units
• Subproject of: FOR 5701: Identification of the formation mechanisms of white etching cracks and fine granular dark areas during fatigue loading – parallels and differences (White and Dark)