Influences of heterogeneous nano-structure developed in heavily cold-rolled austenitic stain-less steel on texture and ductility

SUS316LN austenitic stainless steel was simply and heavily cold-rolled up to 92% reduction in thickness. The microstructure developed was composed of complicated heterogeneous nano-structure; "eye-shaped" twin domains, which were surrounded by shear bands, were embedded in low-angle lamellar boundaries. The cold-rolled austenitic steel exhibited marvelous high strength of 1.95 GPa when tensile tested normal to the rolling direction, while lower strength of 1.57 GPa along the rolling direction. Mod-erate ductility around 10 % was still retained in spite of the high strength. The superior mechanical properties of the heavily cold-rolled austenitic stainless steel would be attributed to complicated heterogeneous nano-structures. These achieved strengths were comparable with those obtained by methods of severe plastic deformation. ? 2017 The Japan Institute of Metals and Materials.