Comparison of a low carbon steel processed by Cold Rolling (CR) and Asymmetrical Rolling (ASR): Heterogeneity in strain path, texture, microstructure and mechanical properties

A low carbon steel was processed by Cold Rolling (CR) and Asymmetrical (ASR) at room temperature until 200 μm thickness reduction using multiple rolling passes of 25 μm. ASR process induced a soft curvature with 45.7 mm length 128.8 radius, while the CR did not show any curvature. Materials showed differences in strain path as well texture microstructure evolution, only concerning mode deformation but also across sheet thickness. The hardness tensile tests indicated higher strength after processing than for same reduction. Changes dislocation densities grain size were more pronounced surface neighborhoods material as-received (AR) conditions, homogeneous Synchrotron measurements allowed to build dislocations crystal distribution functions. These functions demonstrated that zones condition, high correspond grains developing components. In contrast, highest center zone formed inside smallest crystals shear orientations. By ASR, heterogeneous hard surfaces generated small reductions narrow thick sheet. CR, increase obtained throughout sheet's thickness, avoiding material. It found distributions geometrically necessary (GNDs) responsible additional hardening.