Study on the behavior of medium carbon vanadium microalloyed steel by hot compression test

Abstract

This article investigates the hot working behavior of medium carbon vanadium microalloyed steel by hot compression tests over the temperature range of 850–1100 °C and strain rate range of 0.001–0.5 s −1 to strain of 0.8. In this study, the general constitutive equations were used to determine the hot working constants. The peak stress ( σ P) and strain ( ɛ P) for initiation of dynamic recrystallization (DRX) at different temperatures and strain rates were calculated. The power law, exponential and hyperbolic sinusoidal types of Zener–Hollomon equations were used to determine the hot deformation activation energy ( Q). The results suggested that the highest correlation coefficient was achieved for the hyperbolic sine law for the studied material. The magnitude of hot deformation activation energy ( Q) was obtained as 319.910 kJ/mol. The classical single peak DRX was observed in most of temperatures and strain rates. However, for temperature of 1100 °C and strain rates of 0.001 s −1, 0.01 s −1, and also for temperature of 950 °C and strain rate of 0.001 s −1 the multiple peak dynamic recrystallization (MDRX) was observed, which showed that the ‘recrystallization’ was an observed strain rate behavior.