Micromechanical failure analysis and tensile behavior of dual phase steel using 2D and 3D RVEs

Dual phase (DP) steels contain of soft ferrite and hard martensite phases. The features of these steels are high strength and ductility that make them attractive especially in the automotive industries and related fields. In the past, researches were conducted to analyze the behavior of DP steels based on the micromechanical and macro mechanical simulation using two-dimensional RVEs . The researchers have analyzed the failure mechanism of DP steel using simulation of uniaxial tensile test based on 2D RVE. Analysis of 3D RVE can be considered for more detailed investigation of failure mechanisms and modification of 2D RVEs. In this paper, prediction of deformation pattern and damage mechanisms of DP steels and failure of specimens are performed at micro scale using finite elements (FE) method. Metallographic and SEM images at three different loads ((i) necking, (ii) after necking, and (iii) failure point) were used to investigate the deformation pattern and failure mechanisms at micro scale. On the other hand the effect of various factors such as 2D and 3D RVEs, mesh size, consideration of large and small deformation theories in FE analyses and also effect of volume fraction of martensite phase on the mechanical properties are examined.