High tensile ductility and high strength in ultrafine-grained low-carbon steel

High tensile ductility and high strength were simultaneously obtained in UFG low-carbon steel prepared by appropriate annealing of cold-rolled martensite–ferrite dual-phase structure. High tensile ductility and high strength are attributed to the coexistence of fully recrystallized ferrite grains with bimodal size distribution and dispersive nanoscale carbides.