Effect of Annealing Temperature on Microstructure and Mechanical Properties of 00Cr21CuTi Stainless Steel Cold-Rolled Sheets

To investigate the evolution of microstructure and mechanical properties in cold-rolled sheets of Ferritic Stainless Steel (FSS) during annealing, a series of annealing tests were performed on 00Cr21CuTi at different temperatures of 930, 990, and 1050 °C. The changes in microstructure at these annealing temperatures were characterized by optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron back-scattered diffraction (EBSD). The influence of annealing temperature on mechanical properties was assessed utilizing a universal tensile testing machine and a laser confocal microscope. The results indicated a gradual decrease in yield strength and tensile strength with increasing annealing temperature, whereas elongation exhibited an upward trend. At an annealing temperature of 930 °C, the yield strength, tensile strength, and elongation of the steel were 251 MPa, 409 MPa, and 30.9%, respectively, with a high product of strength plastic 12.64 GPa·%. This result represented an optimal balance between comprehensive strength and plasticity.