Fracture of high-strength steel notched bars: a fractographic and numerical study

摘要

This paper deals with the fracture of high-strength pearlitic steel bars subjected to multiaxial stress states produced by notches of very different geometries. The research includes a fractographic study of the microscopic modes of fracture by scanning electron microscopy, and a numerical analysis by the finite element method to compute the distribution of continuum mechanics variables in the samples at the fracture instant. The results demonstrate that fracture takes place when the distortional part of the strain energy density reaches a critical value over a critical distance characteristic of the microstructure of the material.