基于相场法的氢脆断裂模拟

The phase field hydrogen embrittlement fracture model is improved by introducing tension-compression split of strain energy. The numerical formulas of the model are provided, besides, the coupling term of concentration field and displacement field is deduced. The matlab software is used to compile the numerical program of phase field hydrogen embrittlement fracture. The modes I and II cracks of hydrogen embrittlement are simulated respectively. The simulation results show that hydrogen ions concentrate at the crack tip where stress concentration happens, and that the hydrogen concentration reduces the critical failure load of the square plate. Compared with the numerical results of the existing models, the improved model can accurately calculate the critical failure load in the mode I crack and capture the embrittlement fracture phenomenon when the phase field and the concentration field are accumulated near the crack tip. Moreover, the improved model can effectively simulate the mode II crack with hydrogen embrittlement.