Hot deformation analysis of lean medium-manganese 0.2C3Mn1.5Si steel suitable for quenching et partitioning process

Abstract

The paper mainly focuses on calculating and comparing a mathematical model of the deformation behaviour at high temperatures. Analysis of the high-temperature plastic behaviour of lean medium-manganese steel 0.2C3Mn1.5Si was carried out in the temperature range of 900-1200 • C and the deformation rate in the range of 0.01-10 s −1 to the maximum value of the true strain 0.8. Microstructural changes were observed using light optical microscopy (LOM) and scanning electron microscopy (SEM). The effect of hot deformation temperature on true stress, peak stress, and the true strain was evaluated using the flow curves. Based on these results, transformations in steel were discussed from the dynamic recovery and recrystallisation point of view. Furthermore, a present model, taking into account the Zener-Hollomon parameter, was applied to predict the true stress and strain over a wide range of temperatures and strain rates. Using constitutive equations, material parameters and activation energy for the investigated steel could be derived. Results demonstrate the use of the model for lean medium-Mn quenching and partitioning steel (Q&P) compositions in hot deformation applications with acceptable accuracy.

A Systematic Review of Medium‐Mn Steels with an Assessment of Fatigue Behavior

“…In an interesting study, Sarkar et al [ 34 ] have employed different thermomechanical processing methods, including hot forging, hot rolling, cold rolling, and intermediate annealing, before subjecting medium‐Mn steels to intercritical annealing to observe the variation in tensile properties. Furthermore, lean medium‐Mn steels are a subgroup of medium‐Mn steels with a reduced Mn content between 3 and 4.5 wt% and C content up to 0.2 wt% that are processed differently [ 35 ] than discussed thermomechanical processing (refer to Figure 2). After cold or hot rolling, these steels are austenitized above the AC 3 temperature and then quenched below the M s temperature.…”

Effects of C and Al Alloying on Constitutive Model Parameters and Hot Deformation Behavior of Medium-Mn Steels

“…The increase in Ti content reduces the deformation activation energy, decreases the original austenite grain size, accelerates the occurrence of the DRX process, and promotes the formation of fine lath martensite microstructure [16]. Krbat'a et al [17] investigated the high-temperature plastic behavior of low manganese Si-containing medium-Mn steel. They analyzed the effects of deformation temperature on peak stress via flow curve and discussed the phase transformation of the steel from the perspective of DRV and DRX.…”