Analyzing crack, KIC and JIC in an API X70 pipeline numerically and theoretically by fracture toughness test samples modeling

An API X70 pipeline steel has been investigated with respect to crack propagation and fracture mechanism. A FEM approach has been applied to simulate the onset of crack propagation. The API X70 pipeline steel simulation has been investigated. Five standard samples of fracture toughness tests simulation in different loading (520-810(MPa)) were used to study crack propagation, while the simulation results were compared with each other. Additionally, in each simulation, plastic zone shape of crack propagation is shown and the results are compared by the theoretical results. Stress diffusion through all parts of simulated samples are shown. All results are extracted in 4(°C) temperature. There is a good agreement between theoretical and simulation results. According to these verifications, presented FEM simulation is reliable to predict crack behavior and calculating KIC and JIC of an API X70 pipeline steel in other kind of loading or crack propagation

Keywords:

KIC , JIC , Crack Behavior , API X70