Effect of microalloying elements (Nb, V and Ti) on the hot flow behavior of high-Mn austenitic twinning induced plasticity (TWIP) steel

摘要

This research work studies the effect of microalloying elements such as Nb, V and Ti on the hot flow behavior of high-Mn austenitic TWIP steel. For this purpose, isothermal uniaxial hot compression tests were carried out at three temperatures (900, 1000 and 1100℃) and four constant strain rates (10~(-1), 10~(-2), 10~(-3) and 10~(-4)s~(-1)). Experimental results revealed that hot flow curves of microalloyed TWIP steels show single peak curves for all test conditions. Results are discussed in terms of the peak stress (σ_P) and peak strain (ε_p) and its dependence on the strain rate (ε) and temperature. The addition of microalloying elements such as Nb, V and Ti in TWIP steels generates a slight increase in the σ_p value, and Ti microalloyed TWIP steel exhibits the highest σ_p value. Hot deformed microstructures were analyzed by the Electron Back-Scattering Diffraction Technique (EBSD). The most important results of the austenitic recrystallized grain refinement were obtained for V and Ti microalloyed TWIP steels.