Effect of Cold Rolling on the Microstructure and High Temperature Properties of 310S Heat-resistant Steel

Abstract The microstructure and high temperature properties of 310S heat-resistant steel were investigated before and after cold rolling with a deformation rate of 10% by using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffractometer (XRD) and tensile testing machine.The results showed that the microstructure of 310S heat-resistant steel remains unchanged with no formation of any new phase observed after cold rolling. The hardness is enhanced from 305.4HV prior to cold rolling to 321.6HV post cold rolling, exhibiting an augmentation of 16.2HV. The 310S heat-resistant steel is carried out a cold-rolling process with a deformation of 10% in the room temperature tensile test. The tensile strength exhibits an increase from 776.6MPa to 806.3MPa, with a difference of 29.7MPa.The yield strength has experienced a significant increase, from 554.4MPa to 679.6MPa, representing a substantial increment of 125.2MPa.The elongation decreased by 20.2%, from 61.9% to 41.7%, after cold rolling. The 310S heat-resistant steel with 0% deformation appears superplasticity at 750°C. The elongation rate reaches 113.1%. The 310S heat-resistant steel with 0% deformation appears fracture oxidation at 800°C. In the process of 700°C to 800°C, the tensile strength of 310S heat-resistant steel with 0% deformation is reduced by 101.9MPa, and the tensile strength of 310S heat-resistant steel with 10% deformation is reduced by 90.9MPa.