Dynamic recrystallization behavior of a kind of Ti-microalloyed high-strength steel

By using thermo-mechanical simulator, OM and SEM, the dynamic recrystallization (DRX) behavior of a kind of Ti-microalloyed high-strength steel was investigated at 850 to 1150 and strain rates from 0.1 to 10 s-1. The activation energy for hot deformation of this Ti-microalloyed steel was calculated to be 381.61 kJ/mol by least square method, while the apparent stress exponent calculated to be 4.59. The equation describing the hot working process was also obtained. The mathematical models of peak strain and critical strain versus Z parameter were deduced. The results show that the peak strain and critical strain all bear linear relationship with lnZ. It's found that this kind of Ti-microalloyed steel is prone to the dynamic recrystallization at higher temperatures and lower strain rates.