HOT TENSILE TESTING OF SAF 2205 DUPLEX STAINLESS STEEL

The changes to the microstructure of the duplex stainless steel SAF 2205 during hot tensile tests were investigated. The dominant restoration mechanisms for ferrite and austenite were dynamic recovery (DRV) and dynamic recrystallization (DRX), respectively. Also, the effect of temperature on the deleterious phase precipitation was investigated. The specimens were tested with hot tensile deformation tests in the temperature range from 800 degrees C to 1100 degrees C. The tensile strength of the investigated steel decreased rapidly in the temperature range from 800 degrees C to 950 degrees C and slowly at the testing temperatures from 1000 degrees C to 1100 degrees C. It was found that SAF 2205 has excellent hot-working properties at temperatures between 950 degrees C and 1100 degrees C. The differences in the mechanical properties of austenite and ferrite along with the precipitation of the sigma-phase represent the most important restrictions during hot working. Optical microscopy was used for the microstructure-evolution analysis in the duplex stainless steel during the hot tensile tests.