Effect of cold rolling and annealing processes on the microstructure and mechanical properties of S32101 lean duplex stainless steel

Lean duplex stainless steel (S32101) is widely used in chemical, petrochemical, and marine industries due to its excellent corrosion resistance and high strength. However, optimizing the balance between strength and ductility through cold rolling and annealing remains a challenge. This study investigates the effects of cold rolling (20–60%) and annealing times (30, 60, 90 min) on the microstructure and mechanical properties of S32101. The results show that increasing cold rolling reduction significantly enhances yield strength but reduces ductility. The best balance of strength and ductility was achieved with 60% cold rolling reduction and 60 min of annealing, resulting in a yield strength of 509 MPa, tensile strength of 730 MPa, and 67% elongation. Insufficient annealing (30 min) caused incomplete phase transformation and limited ductility, while excessive annealing (90 min) led to grain growth and reduced strength. This study provides a systematic analysis of the relationship between cold rolling and annealing parameters, offering valuable insights for optimizing processing techniques for S32101 in industrial applications.