Phase-field-crystal modeling for microcrack propagation and branching of ductile materials

摘要

The phase-field-crystal method is a new multiscale method,which can reproduce physicalphenomena on atomic level and on the diffusion time scale for ductile materials.The morphology ofmicrocrack propagation and crack branching of single crystal ductile materials under the conditionsof tensile are simulated by using phase-field-crystal method.The results show that,the shapeof the notch has a strong effect on crack propagation for different notch shapes with differentstress concentrations.Crack propagation will appears if only the strain reaches a critical valuefor uniaxial tension,and a crack branching will appears if only strain reaches a critical value forbiaxial tension.Supercooling degree takes significant effects on crack propagation.The smallersupercooling degree is (namely,the temperature is higher),the faster crack propagation is and themore crack branches are.It is observed that free energy of system decreases with time increasingand the energy decreases very faster after crack starts to branching.