Annealing softening behaviour of cold-rolled low-carbon steel with a dual-phase structure and the resulting tensile properties

► Ferrite-martensite (F-M) structures are obtained by intercritical heat treatments. ► Cold-rolling and annealing of F-M yield ultrafine ferrite grains and nanocarbides. ► Excellent strength-ductility balance is achieved. ► Annealing softening behaviour of cold-rolled F-M is studied. ► Effect of F-M on softening, microstructure and tensile properties is discussed.