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A Free Energy Model for the Inner Loop Behavior of Pseudoelastic Shape Memory Alloys

Published online by Cambridge University Press:  01 February 2011

Olaf Heintze
Affiliation:
Dept. Mech. & Aero. Eng. Campus Box 7910, 3211 Broughton Hall, North Carolina State Univ., Raleigh, NC 27695-7910
Stefan Seelecke
Affiliation:
Dept. Mech. & Aero. Eng. Campus Box 7910, 3211 Broughton Hall, North Carolina State Univ., Raleigh, NC 27695-7910
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Abstract

The paper presents a free energy model for the pseudoelastic behavior of shape memory alloys. It is based on a stochastic homogenization process, which uses distributions in energy barriers and internal stresses to represent effects typically encountered in polycrystalline materials. This concept leads to a realistic desription of the rate-dependent inner loop behavior, but is characterized by rather long computation times. This is prohibitive in regard to a potential implementation into other numerical codes, such as finite element or optimal control programs or a Matlab/Simulink environment. For this purpose a parameterization method is introduced, which is derived from the concept of a representative single crystal. The approach preserves the desirable properties of the original formulation, at the same time reducing the numerical effort significantly. Finally, we show that the method can reproduce the experimentally observed behavior accurately over a large range of strain rates including the minor loop behavior.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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References

[1] Bergman, A. and Seelecke, S.. Experimental investigation of inner hystersis loops and ratedependence in pseudoelastic niti wires. Acta Mater., 2005. submitted.Google Scholar
[2] Bertotti, G., editor. Hysteresis in Magnetism, For Physicists, Material Scientists, and Engineers. Academic Press, 1998.Google Scholar
[3] and, Z. Bo Lagoudas, D. C.. Thermomechanical modeling of polycrystalline SMAs under cyclic loading, Part I: theoretical derivations. Int. J. Eng. Sci., 37:1089ω1140, 1999.Google Scholar
[4] Bo, Z. and Lagoudas, D. C.. Thermomechanical modeling of polycrystalline SMAs under cyclic loading, Part II: material characterization and experimental results for a stable transformation cycle. Int. J. Eng. Sci., 37:1141ω1173, 1999.Google Scholar
[5] Bo, Z. and Lagoudas, D. C.. Thermomechanical modeling of polycrystalline SMAs under cyclic loading, Part III: evolution of plastic strains and two-way shape memory effect. Int. J. Eng. Sci., 37:1175ω1203, 1999.Google Scholar
[6] Bo, Z. and Lagoudas, D. C.. Thermomechanical modeling of polycrystalline SMAs under cyclic loading, Part IV: modeling of minor hysteresis loops. Int. J. Eng. Sci., 37:1205ω1249, 1999.Google Scholar
[7] Entchev, P. B. and Lagoudas, D. C.. Modeling of transformation-induced plasticity and its effect on the behavior of porous shape memory alloys. part i: Porous sma response. Mech. Mat., 36:893ω913, 2004.Google Scholar
[8] Hairer, E. and Wanner, G.. Solving Ordinary Differential Equations II. Stiff and Differentialalgebraic Problems. Springer Series in Computational Mathematics. Springer-Verlag, 1991.Google Scholar
[9] Heintze, O.. A Computationally Ef oient Free Energy Model for Shape Memory Alloys - Experiments and Theory. PhD thesis, North Carolina State University, Raleigh, NC, USA, 2004.Google Scholar
[10] and, M. Huang Brinson, L. C.. A multivariant model for single crystal shape memory alloy behavior. J. Mech. Phys. Solids, 46(8):1379ω1409, 1998.Google Scholar
[11] Ikeda, T., Nae, F. A., Naito, H., and Matsuzaki, Y.. Constitutive model of shape memory alloys for unidirectional loading considering inner hysteresis loops. Smart Mat. Struct., 13:916ω925, 2004.Google Scholar
[12] Khan, M. M., Lagoudas, D. C., Mayes, J. J., and Henderson, B. K.. Pseudoelastic sma spring elements for passive vibration isolation: Part i - modeling. J. Intelligent Mat. Syst. Struct., 15:415441, 2004.Google Scholar
[13] Lagoudas, D. C. and Entchev, P. B.. Modeling of transformation-induced plasticity and its effect on the behavior of porous shape memory alloys. part i: Constitutive model for fully dense smas. Mech. Mat., 36:865ω892, 2004.Google Scholar
[14] and, Z. K. Lu Weng, G. J.. Martensitic transformation and stress-strain relations of shape-memory alloys. J. Mech. Phys. Solids, 45(11/12):1905ω1928, 1997.Google Scholar
[15] Lu, Z. K. and Weng, G. J.. A self-consistent model for the stress-strain behavior of shape-memory alloy polycrystals. Acta Mater., 46(15):5423ω5433, 1998.Google Scholar
[16] Massad, J. E.. Macroscopic Models for Shape Memory Alloy Characterization and Design. PhD thesis, North Carolina State University, Raleigh, NC, USA, 2003.Google Scholar
[17] Massad, J. E. and Smith, R. C.. A domain wall model for hysteresis in ferroelastic materials. J. Intelligent Mat. Syst. Struct., 14(7):455ω471, 2003.Google Scholar
[18] Seelecke, S.. Zur Thermodynamik von Formgedachtnislegierungen. Number 433 in Fortschr.-Ber. VDI Reihe 5. VDI Verlag Dusseldorf, 1996.Google Scholar