Kinetics of Formation of Austenite and Effect of Heating in the Intercritical Temperature Range on the Structure of Steel 08G2B

Abstract

The kinetics of formation of austenite in steel 08G2B under continuous heating at a rate of 0.3 and 90 K/sec to the intercritical temperature range is studied with the help of x-ray diffraction, dilatometric and calorimetric methods of analysis. The tests are performed for specimens in two initial conditions, i.e., after recrystallization-free controlled rolling with accelerated cooling and after water quenching from 1000°C. It is shown that the α – γ transformation under the conditions studied may be treated as a diffusion-controlled isokinetic reaction occurring in two stages with rapid formation of austenite nuclei primarily over the boundaries of initial austenite grains.