Hot deformation behavior and flow stress model of F40MnV steel

Abstract

Single hit compression tests were performed at 1 223–1 473 K and strain rate of 0.1–10 s⁻¹ to study hot deformation behavior and flow stress model of F40MnV steel. The dependence of the peak stress, initial stress, saturation stress, steady state stress and peak stain on Zener-Hollomon parameter were obtained. The mathematical models of dynamic recrystallization fraction and grain size were also obtained. Based on the tested data, the flow stress model of F40MnV steel was established in dynamic recovery region and dynamic recrystallization region, respectively. The results show that the activation energy for dynamic recrystallization is 278.6 kJ/mol by regression analysis. The flow stress model of F40MnV steel is proved to approximate the tested data and suitable for numerical simulation of hot forging.

Keywords

microalloyed forging steel / flow stress / dynamic recovery / dynamic recrystallization / Zener-Hollomon parameter

References

[1] LaasraouiA., JonasJ. J.. Prediction of steel flow stresses at high temperatures and strain rates[J]. Metallurgical Transactions A, 1991, 22A(7): 1545-1558

[2] SerajzadehS., KarimiT. A.. Prediction of flow stress at hot working condition[J]. Mechanics Research Communications, 2003, 30(1): 87-93

[3] KimS. I., LeeY., ByonS. M.. Study on constitutive relation of AISI 4140 steel subject to large strain at elevated temperatures[J]. Journal of Materials Processing Technology, 2003, 140(1/3): 84-89

[4] SerajzadehS., KarimiT. A.. An investigation on the effect of carbon and silicon on flow behavior of steel[J]. Materials and Design, 2002, 23(3): 271-276

[5] MedinaS. F., HernandezC. A.. Modelling of the dynamic recrystallization of austenite in low alloy and microalloyed steels[J]. Acta Materialia, 1996, 44(1): 165-171

[6] HernandezC. A., MedinaS. F., RuizJ.. Modelling austenite flow curves in low alloy and microalloyed steels[J]. Acta Materialia, 1996, 44(1): 155-163

[7] NaylorD. J.. Microalloyed forging steels[J]. Materials Science Forum, 1998, 284/286: 83-94

[8] Gonzalez-BaquetI., KasparR., RichterJ., et al.. Microalloying and a new post forging treatment of medium carbon steels[J]. Materials Science Forum, 1998, 284/286: 411-418

[9] de ArdoA. J.. Microalloyed strip steels for the 21st century[J]. Materials Science Forum, 1998, 284/286: 15-26

[10] DongC.-r., RenH.-o., JinT.-z., et al.Microalloyed Forging Steel[M], 2000, Beijing, Metallurgical Industry Press

[11] McqueenH. J., YueS., RyanN. D., et al.. Hot working characteristics of steels in austenitic state[J]. Journal of Materials Processing Technology, 1995, 53(1/2): 293-310

[12] SellarsC. M., WhitemanJ. A.. Recrystallization and grain growth in hot rolling[J]. Metal Science, 1979, 13(3/4): 187-194

[13] KarhausenK., KoppR.. Model for integrated process and microstructure simulation in hot forming[J]. Steel Research, 1992, 63(6): 247-256

[14] ImbertC. A. C., McqueenH. J.. Dynamic recrystallization of A2 and M2 tool steels[J]. Materials Science and Engineering A, 2001, 313(1/2): 104-116

[15] KongL. X., HodgsonP. D., WangB.. Development of constitutive models for metal forming with cyclic strain softening[J]. Journal of Materials Processing Technology, 1999, 89/90: 44-50

[16] EstrinY., MeckingH.. Unified phenomenological description of work harding and creep based on one-parameter models[J]. Acta Metallurgica, 1984, 32(1): 57-70

[17] MeckingH., KocksU. F.. Kinetics of flow and strain-hardening[J]. Acta Metallurgica, 1981, 29(11): 1865-1875