Modeling of the hot deformation behavior of boron microalloyed steels under uniaxial hot-compression conditions

The present study shows that the hot deformation behavior of boron microalloyed steels can be quantitatively described by constitutive equations. These equations take into account both dynamic recovery and recrystallization phenomena. They have been fitted Using experimental data taken from hot compression tests Of four boron microalloyed steels in order to determine their characteristic parameters. The tests were carried Out over a wide range of temperatures (950, 1000, 1050 and 1100 degrees C) and strain rates (10(-3), 10(-2) and 10(-1) s(-1)). The analysis of the characteristic parameters of the constitutive equations describing the hot flow behavior of these steels shows that boron additions play a major role in softening mechanisms rather than on hardening. A quantification of the boron effect is also presented. The experimental data were compared with the predictions of the proposed model and an excellent agreement between measured and predicted values for all boron microalloyed steels over a wide range of temperatures and strain rates was obtained.