Achievement of high strength-ductility combination in austenitic and ferritic duplex stainless steel by heterogeneous deformation

Abstract

In this work, heterostructured duplex stainless steel consisting of fine-grained austenite and bimodal-grained ferrite was prepared by heavy cold rolling and 2-min annealing at 1050 °C. The tailored steel achieved an excellent combination of high strength with a yield stress of ∼710 MPa and high ductility with a tensile elongation of ∼43%. The results revealed that the plastic incompatibilities between the constituent phases arising from the microstructural heterogeneity contributed to the significant partitioning of plastic strain, and the respectable strength–ductility synergy was attributed to hetero-deformation induced strengthening and strain hardening.

Keywords

• Duplex stainless steel
• Heterogeneous deformation
• Ductility
• Strain hardening