Scale-bridging analysis of heterogeneous deformation behavior in austenitic stainless steel

Abstract

In this study, scale-bridging analysis of heterogeneous deformation behavior in SUS310S austenitic stainless steel was conducted using X-ray line profile analysis, digital image correlation (DIC), and transmission electron microscopy (TEM). Specimens were prepared using tensile strain of 3%–40% at 298 ± 2 K. According to the X-ray line profile analysis, increasing strain increased dislocation density and decreased crystallite size. Furthermore, using DIC, low- and high-strain regions were observed in the early stages of deformation. TEM analysis showed that dislocations in the low-strain region were rarely tangled, while in the high-strain region, tangled dislocation and increased dislocation density were observed. TEM analysis also demonstrated that the formation of dislocation cells was promoted in the later stages of deformation, and the size of dislocation cells decreased as the strain increased. Moreover, we showed quantitative relationships between dislocation density, dislocation cell size, and crystallite size based on our findings.