Optimization the working parameters of as-forged 42CrMo steel by constitutive equation-dynamic recrystallization equation and processing maps

42CrMo steel belongs to low-alloy medium carbon steel and also belongs to ultra-high strength steel. In this study, thermal compression tests (800 degrees C- 1200 degrees C, 0.01s(-1)- 10s(-1)) and subsequent calculations proved that many material constants of 42CrMo alloy steel have a similar functional relationship with Z parameter: Material constants = a*Zb. The thermal processing maps under strains of 0.2, 0.4, 0.6 and 0.8 were established, and the practical application of the processing maps was verified in combination with metallographic diagram analysis. The optimum thermal processing parameters range of the material was obtained: the temperature range of 1000 degrees C- 1125 degrees C and the strain rate range of 3.16 s(-1) - 10s(-1).The dynamic recrystallization volume fraction model and grain size model of the material were established, and the typical sigmodal curve was obtained. The hot workability and recrystallization behavior of 42CrMo were further analyzed. (C) 2020 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).