A phenomenological two-phase constitutive model for porous shape memory alloys

Date

2012-07-01

Author

EL SAYED, TAMER
Gürses, Ercan
SIDDIQ, AMIR

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We present a two-phase constitutive model for pseudoelastoplastic behavior of porous shape memory alloys (SMAs). The model consists of a dense SMA phase and a porous plasticity phase. The overall response of the porous SMA is obtained by a weighted average of responses of individual phases. Based on the chosen constitutive model parameters, the model incorporates the pseudoelastic and pseudoplastic behavior simultaneously (commonly reported for porous SMAs) as well as sequentially (i.e. dense SMAs; pseudoelastic deformation followed by the pseudoplastic deformation until failure). The presented model also incorporates failure due to the deviatoric (shear band formation) and volumetric (void growth and coalescence) plastic deformation. The model is calibrated by representative volume elements (RVEs) with different sizes of spherical voids that are solved by unit cell finite element calculations. The overall response of the model is tested against experimental results from literature. Finally, application of the presented constitutive model has been presented by performing finite element simulations of the deformation and failure in unaixial dog-bone shaped specimen and compact tension (CT) test specimen. Results show a good agreement with the experimental data reported in the literature.

Subject Keywords

Porous shape memory alloys, Unit cell calculations, Constitutive model, Porous plasticity

URI

https://hdl.handle.net/11511/34745

Journal

COMPUTATIONAL MATERIALS SCIENCE

DOI

https://doi.org/10.1016/j.commatsci.2012.02.031

Collections

Department of Aerospace Engineering, Article

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Citation Formats

T. EL SAYED, E. Gürses, and A. SIDDIQ, “A phenomenological two-phase constitutive model for porous shape memory alloys,” COMPUTATIONAL MATERIALS SCIENCE, pp. 44–52, 2012, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/34745.