The influence of microstructure on ductile fracture initiation in low-alloyed steel

Abstract

In this paper the quantitative microstructural analysis of low-alloyed pressure vessel steel has been discussed. The values of volume fraction and mean free path of non-metallic inclusions determined in that way were used in the numerical analysis. A series of elastic-plastic calculations of round smooth specimen and compact tension (CT) specimen was made using Finite elements (FE) method under conditions of ductile fracture initiation of tested steel, followed by large plastic deformation. The influence of microstructure of tested ferritic steel on crack initiation and growth was considered using two micromechanical models.