Processing of Grade a Low Carbon Steel by Equal Channel Angular Pressing

Abstract

The present study aims to analyze the effect of equal channel angular pressing (ECAP) on the microstructural and mechanical properties as well as the impact energy of low carbon steel. Grade A steel was processed using ECAP. One pass of ECAP did not cause a considerable decrease in the grain size of the steel. It brought about two different microstructures on the flow and transverse planes of an ECAP billet, instead. The microstructure consists of elongated ferrite and perlite grains aligned in a direction having mainly 45° angle with the extrusion direction on the flow plane while nearly equiaxed grains were formed on the transverse plane. These differences between the microstructures of two different planes of the ECAP sample are attributed to the share planes that are operative during ECAP. ECAP increased the hardness and strength values of the steel significantly due to the increase in the dislocation density during the process. However, it decreased the elongation to failure considerably. It was found that the impact energy of the ECAP-processed sample is dependent on the notch position of the Charpy impact test sample.