フェライト結晶粒内のへき開面形成シミュレーション

抄録

Dependence of cleavage fracture facet on test temperature is found out in the authors’ previous experimental study. In the present study, a numerical model is developed in order to simulate the formation of the cleavage fracture facet. In this model, three grains are modeled as cubes and their sizes are independently introduced by using the distribution of the test steel. The condition of the breakthrough at grain boundary is defined based on the local fracture stress criterion. The fracture facets in a grain are evaluated by mechanical and topological patterns of fracture. The numerical results show that the multiple fracture facets are frequently formed in one grain and the size of fracture facets become small in case of low fracture arrest toughness. That is, the influence of temperature on the fracture facet distribution in experimental results is simulated by the microscopic fracture arrest toughness in the developed numerical model.