Critical conditions of dynamic recrystallization of SAE8620RH gear steel [SAE8620RH齿轮钢的动态再结晶临界条件]

作者：Zhang Q.; Li L.-J.^*; Chen S.-J.; Peng Z.-W.; Gao J.-X.

来源：Transactions of Materials and Heat Treatment, 2020, 41(6): 160-167.

DOI：10.13289/j.issn.1009-6264.2019-0565

• Critical condition
• Dynamic recrystallization
• Hot deformation activation energy
• SAE8620RH gear steel
• Work hardening rate

The dynamic recrystallization behavior of SAE8620RH gear steel under deformation temperature of 850-1100℃ and strain rate of 0.02-8 s-1 was studied by single-pass compression test on the Gleeble-3800 thermal simulator. The Zener-Hollomon parameters were calculated based on the stress-strain curves, the constitutive equation was constructed by hyperbolic sine equation, and the flow stress data was processed by the method of work hardening rate. The results show that the activation energy of high temperature deformation of the SAE8620RH steel is 295.274 kJ/mol. Combined with the inflection point of the curves of lnθ-ε and the criterion minimum value of the curves of dlnθ/dε-ε, the critical condition of dynamic recrystallization in the thermoplastic deformation of the SAE8620RH steel is determined, and the functional relationship between the critical condition and the temperature compensated strain rate factor Z is established: εc=3.21×10-4Z0.23687.

• 单位
  华南理工大学