عنوان مقاله [English]
In this research, the effect of cast microstructure on the recovery and recrystallization process of 2304 duplex stainless steel has been investigated. The specimens were hot-formed at low temperatures of 850°C and 950 °C and high temperatures of 1050 and 1150°C by using hot compression test machine at strain rates of 0.001 to 1 s−1. The microstructure changes were studied using optical microscopy equipped by image analyzer. In addition, the apparent activation energies were determined based on the stress-strain hot compression curves. The results show that during of hot deformation of 2304 two-phase stainless steel, the restoration mechanisms in two phase are different, it is performed by dynamic recovery in the ferrite phase and by recrystallization process in the austenite phase. The apparent activation energy Q of the cast microstructure at 850 and 1150 temperatures of hot working is 325 and 150 kJ/mol respectively, which is lower than the applied wrought microstructure.
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