Hot deformation behavior and processing map of ultra-high strength stainless steel

Abstract

The 10Cr13Co13Mo5Ni3W1VE(S280) ultra-high strength stainless steel was subjected to isothermal and constant strain rate compression experiments at deformation temperature of 800-1150 °C, the strain rate of 0.001-10 s–1, and the deformation amount of 70% by using Thermecmaster-Z thermal simulation testing machine. The hot deformation behavior of the steel was analyzed, and the processing maps based on Murty instability criterion were established. The results show that the flow stress of S280 ultra-high strength stainless steel during hot deformation is sensitive to deformation temperature and strain rate. With the increase of strain rate and the decrease of deformation temperature, the flow stress increases significantly. It is determined that the region of instability occurs in the temperature range of 800-1040 °C and strain rate range of 0.06-10 s–1, and the corresponding instability deformation mechanism is mainly flow localization. The desired parameters are 1095-1150 ℃ and 0.001-0.04 s–1 with the plastic deformation mechanism of dynamic recrystallization, and the optimum parameters are around 1125 ℃ and 0.001 s–1.

Keywords

• s280 ultra-high strength stainless steel
• hot deformation behavior
• processing map
• dynamic recrystallization
• process parameter optimization