Nano-grain evolution in austenitic stainless steel during multi-directional forging

▶ Severe plastic deformation of austenitic stainless steel (SUS 316)by multidirectional forging. ▶ Grain fragmentation by the coordinated effects of mechanical twinning, martensitic transformation and continuous dynamic recrystallization. ▶ Uniform evolution of packetswith the size (dp) from 40 nm to 100 nm. ▶ Ultrafine grains with an average grain size much lower than 50 nm. ▶ The superior balance of strength and ductility; 2.1 GPa UTS and 20% total elongation. ▶