Warm Deformation of Low Carbon Steel Using Forward Extrusion-Equal Channel Angular Pressing Technique

 A combination of extrusion and equal channel angular pressing (ECAP) was used to deform a plain low carbon steel. This process consists of two successive deformations by extrusion and ECAP in a single die (Ex-ECAP). Cylindrical samples were heated to predefined temperatures (650 and 850 ℃) and then pressed through a die channel with crosshead speed of 10 mm/s. Microstructure and resultant mechanical properties of processed material were studied. The results showed that pressing temperature has a significant effect on the resultant microstructure. While at 650 ℃, the cold worked structure with elongated ferrite grains were obtained, and at 850 ℃ the microstructure consisted of elongated ferrite grains and very fine grains at their boundaries as a consequence of continuous dynamic recrystallization (CDRX) of ferrite phase. Also at 850 ℃, a particular microstructure consisted of cold worked ferrite and static recrystallized grains on shear bands was obtained.