Engineering Transactions, 45, 3-4, pp. 419-431, 1997

Numerical Modelling of Adiabatic Shear Bad Formation in a Twisting Test

A. Glema
Poznań University of Technology, Poznań
Poland

W. Kąkol
Poznań University of Technology, Poznań
Poland

T. Łodygowski
Poznań University of Technology, Poznań
Poland

The objective of the paper is the investigation of adiabatic shear band localized fracture phenomenon in a tubular specimen during dynamic loading processes. The fracture occurs as a result of an adiabatic shear band localization attributed to a plastic instability implied by ther­mal softening during dynamic plastic flow. The formulation of the physical problem is adopted following the paper by T. ŁODYGOWSKI and P. PERZYNA [8]. For regularized elasto-viscoplastic model, the numerical investigation of the three-dimensional dynamic adiabatic deformation in a particular body at nominal strain rates ranging from 103 to 104 s- 1 is presented. The attention is focussed on the discussion, which finite element models are acceptable for computational simulation of the real experiments, taking into account both the physical point of view and the computational efficiency. The restrictions in the creation of arbitrary 3-D models are discussed and for the case under consideration, a 2-D shell model is proposed. The results of computa­tions (plastic strains and temperature rise) obtained in the environment of ABAQUS package [1] confirm the laboratory observations with satisfying accuracy.

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References

ABAQUS 5.6 Manuals, Hibbitt, Karlsson & Sorensen Inc., 1996.

R.C. BATRA and X. ZHANG, On the propagation of a shear band in a steel tube, Int. J. Plasticity, 1993.

A. GLEMA, T. ŁODYGOWSKI and P. PERZYNA, Effects of microdamage in plastic strain localization, XIII Polish Conf. Comp. Meth. in Mech., pp. 451-458, Poznań, May 5-8, 1997.

K.A. HARTLEY, J. DUFFY and R.H. HAWLEY, Measurement of the temperature profile during shear band formulation in steels deforming at high strain rates, J. Mech. Phys. Solids, 35, 283-301, 1987.

B. LORET and J.H. PREVOST, Dynamic strain localization in elasto-visco-plastic solids. Part 1. General formulation and one-dimensional examples, Comp. Meth. in Appl. Mech. Engng., 83, 247-273, 1990.

T. ŁODYGOWSKI, On avoiding of spurious mesh sensitivity in numerical analysis of plastic strain localization, CAMES, 2, 231-248, 1995.

T. ŁODYGOWSKI, Theoretical and numerical aspects of plastic strain localization, Wyd. Politechniki Poznańskiej, No. 312, 1996.

T. ŁODYGOWSKI and P. PERZYNA, Numerical modelling of localized fracture of inelastic solids in dynamic loading processes, Int. J. Num. Meth. Engng., 1996, [in press].

A. MARCHAND and J. DUFFY, An experimental study of the formation process of adiabatic shear bands in a structural steel, J. Mech. Phys. Solids, 36, 251-283, 1988.

A.M. MERZER, Modelling of adiabatic shear band development from small imperfections, J. Mech. Phys. Solids, 30, 323-338, 1982.

J.A. NEMES and J. EFTIS, Constitutive modelling on the dynamic fracture of smooth tensile bars, Int. J. Plasticity, 9, 243-270, 1993.

P. PERZYNA, The constitutive equations for rate sensitive plastic materials, Quart. Appl. Math., 20, 321-332, 1963.

P. PERZYNA, Thermodynamic theory of viscoplasticity, Advances in Appl. Mech., 11, 313-354, 1971.

P. PERZYNA, Instability phenomena and adiabatic shear band localization in thermoplastic flow processes, Acta Mech., 106, 173-205, 1994.

H.M. ZBIB and J.S. JURBAN, Dynamic shear banding: A three-dimensional analysis, Int. J. Plasticity, 8, 619-641, 1992.




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