EVALUATION OF STRENGTH CHARACTERISTICS CONSIDERING MICROSCOPIC HETEROGENEITY OF STRUCTURAL STEELS AND WELD ZONE BY USING FEM-MD COUPLING METHOD

摘要

The strength properties of structural steels or their weld zone are influenced by the microscopic heterogeneity. It is im-portant to investigate the stress distribution for clarification of the mechanism of fracture and the material design by consider-ing a grain boundary or its neighborhood because either can be a zone where the stress concentration is likely to occur due to a mismatch of the displacement. For this purpose, FEM-MD cou-pling method is one of the useful methods because it can treat the mismatch of the displacement caused by the microscopic heterogeneity. In this study, FEM-MD coupling method is pro-posed and the influence of the microscopic heterogeneity of steels is investigated by using FEM-MD coupling method.