An attempt has been made to develop dual-phase (d-p) steels from cold-rolled plain carbon sheet steels. Three plain carbon sheet steels with carbon content of 0.075, 0.095 and 0.2 wt.% have been selected. Intercritical heat treatments at 740 °C and holding times of 0.5, 1, 1.5, 2, 3, 4, 5, 8, 10, 15, and 30 minutes at this temperature followed by fast water quenching were used. A good combination of strength and ductility of d-p steels has been observed for the heat treatment cycle of 740 °C for 1.5 minutes and WQ. D-p steel with 0.075 wt.% carbon has shown an ultimate tensile strength of 560 MPa and a ductility (uniform elongation) of 16% whereas the starting material i.e. plain carbon cold rolled sheet steel, has a UTS of 382 MPa and a ductility of5.5 %. Similar improvements have been observed for other steels. These improvements in the mechanical properties are explained on the basis of the cold work energy and the kinetics of austenitisation during intercritical annealing.