Engineering Transactions, 47, 3-4, pp. 321–337, 1999

Modelling of Hot Metal Forming in the Conditions of Variable Strain Rates and Temperatures

M. Pietrzyk
University of Mining and Metallurgy

The model, based on the internal variable theory, describing behaviour of metals during hot plastic deformation, is presented. This model is coupled with a typical thermal-mechanical finite-element solution for hot metal forming processes. Problems connected with simulation of hot forming of steel and aluminium alloys in the variable conditions are discussed. Two types of materials are considered: (i) those showing a delay of the response in transient conditions, (ii) those reaching without delay a new level determined by the equation of state for new conditions of deformation. The model is verified experimentally.
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C.M. SELLARS, Modelling – an interdisciplinary activity, Proc. Symp. Mathematical Modelling of Hot Rolling of Steel [Ed.] S. Yue, Hamilton 1990, 1–18.

P.D. HODGSON, D. MCFARLANE and R.K. GIBBS, The mathematical modelling of hot rolling: accuracy vs. utility, Proc. Conf. Modelling of Metal Rolling Processes, London 1993, 2–15.

Q. ZNU and C.M. SELLARS, Recrystallisation behaviour in tension/tension and tension/compression hot deformation of Al-2Mg, Proc. Conf., Thermo-Mechanical Processing in Theory, Modelling and Practice, Eds., B. Hutchinson, M. Andersson, G. Engberg, B. Karlsson, T. Siwecki, Sztokholm 1996, 193–200.

A. KORBEL, Perspectives of the control of mechanical performance of metals during forming operations, Proc. Conf. Metal Forming'92 [Eds.] M. Pietrzyk, J. Kusiak, J. Mat. Proc. Technol., 34, 41–50, 1992.

Y. ESTRIN, Dislocation density related constitutive modelling, unified constitutive laws of plastic deformation [Eds.] A.S. Krausz, K. Krausz, Academic Press, 1996.

H. MECKING, U.F. KOCKS, Kinetics of flow and strain-hardening, Acta Metall., 29, 1865–1875, 1981.

Y. ESTRIN, H. MECKING, A unified phenomenological description of work hardening and creep based on one-parameter models, Acta Metall., 32, 57–70, 1984.

R. SANDSTROM, R. LAGNEBORG, A model for hot working occurring by recrystallisation, Acta Metall., 23, 387–398, 1975.

R. SANDSTROM, R. LAGNEBORG, A model for static recrystallisation after hot deformation, Acta Metall., 23, 481–488, 1975.

W. ROBERTS, B. AHLBLOM, A mucleation criterion for dynamic recrystallisation during hot working, Acta Metall. 26, 801–813, 1978.

H.J. McQUEEN, Controversies in the theory of dynamic recrystallisation, Mat. Sci. Forum, 113–115, 429–434, 1993.

S. WIERZBIŃSKI and A. KORBEL, Some aspects of dynamic restoration processes in Cu-lONi alloy, High Temp. Metar. Proc., 12, 105–116, 1993.

C.H.J. DAVIES, Dynamics of the evolution of dislocation populations, Scr. Metall. Mater., 30, 349–353, 1994.

M. PIETRZYK, Numerical aspects of the simulation of hot metal forming using internal variable method, Metall. Foundry Eng., 20, 429–439, 1994.

M. PIETRZYK, R. KUZIAK, Application of the internal variable approach to the simulation of microstructural phenomena in hot forming of eutectoid steel, Proc. Conf. EUROMAT'95, Padua 1995, 239–244.

M. PIETRZYK, J.G. LENARD, Thermal-mechanical modelling of the flat rolling processes, Springer Verlag, Berlin 1991.

M. PIETRZYK, C. ROUCOULES, P.D. HODGSON, Dislocation model for work hardening and recrystallisation applied to the finite-element simulation of hot forming, Proc. Conf. NUMIFORM'95, [Eds.] S.-F. Shen, P.R. Dawson, Ithaca 1995, 315–320.

M. PIETRZYK and R. KUZIAK, Validation of the history dependent flow stress model for hot forming of metals, Proc. Conf. COMPLAS 5 [Eds.] D.R.J. Owen, E. Onate, E. Hinton, Barcelona 1997, 1363–1368.

R. KUZIAK, private information, Gliwice 1998.

Q. ZHU, H.R. SHERCLIFF, C.M. SELLARS, Modelling hot deformation behaviour based on evolution of dislocation substructures, Proc. Conf. THERMEC'97, [Eds.] T. Chandra, T. Sakai, Wollongong 1997, 2039–2045.

C.M. SELLARS, Q. ZHU, Microstructural evolution during hot deformation of aluminiummagnesium alloys, Proc. Symp. Hot Deformation of Aluminium, Rosemont 1998 (in press).

DOI: 10.24423/engtrans.635.1999

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