Influences of Manganese on the Hot Deformation of Austenitic Fe-Mn-Si-Al Alloys

摘要

Influences of Mn on hot deformation behavior of austenitic Fe-Mn-Si-Al alloys were investigated by hot compression tests on Gleeble 3500 thermo-mechanical simulator in temperature range from 900 to 1100 °C and at strain rate range from 0.01 to 1 s^-1. The results show that the peak stress and the hot deformation activation energy of the Fe-Mn-Si-Al alloy during hot deformation increase with increasing Mn content. The hot deformation activation energies are determined as 361.17 kJ/mol and 411.17 kJ/mol for Fe-20Mn-3Si-3Al alloy (20Mn alloy) and Fe-25Mn-3Si-3Al alloy (25Mn alloy), respectively. Furthermore, the softening mechanism of the Fe-Mn-Si-Al alloy during hot deformation varies with the variation of Mn content. The dynamic recovery (DRV) is the main softening mechanism for 20Mn alloy, and the dynamic recrystallization (DRX) is the main softening mechanism for 25Mn alloy within the investigated ranges of strain rate and temperature. The influences of Mn content on material constants in constitutive equations of both the alloys were also determined, and then the constitutive equations for the peak stresses for 20Mn alloy and 25Mn alloy were given.