Structure and Mechanical Properties of AISI1045 in the Helical Rolling–Pressing Process

Abstract

The structure and mechanical properties of steel AISI 1045 subjected to three passes of the combined process “helical rolling–pressing” at a temperature of 500 °C were investigated. During the helical rolling–pressing process, the structure was substantially crushed to ultrafine-grained state, as the structure of steel AISI 1045 with an average grain size of 25 µm after deformation was decreased by 25 times, the average grain size was 1 µm. The values of tensile strength and yield strength increase in three passes from 619 to 925 MPa and from 545 to 867 MPa, respectively. The relative contraction after rupture varies from 42 to 35%; but the change is not as significant as in usual helical rolling. The combined helical rolling–pressing process is an effective way to form an ultrafine-grained structure and improve the mechanical properties of AISI 1045 steel.