An extended thermomechanically coupled 3D rate-dependent model for pseudoelastic SMAs under cyclic loading. (15th August 2017)

• Record Type: Journal Article
• Authors: Gu, Xiaojun; Zhang, Weihong; Zaki, Wael; Moumni, Ziad
• Is Part Of: Smart materials and structures. Volume 26:Number 9(2017:Sep.)
• Publication Date: 2017-08-15
• Subjects: shape memory alloys -- thermomechanical coupling -- nonproportional loading -- residual strain -- cyclic loading; Smart materials -- Periodicals; Strucural design -- Periodicals; 620.11
• DOI: 10.1088/1361-665X/aa7c36
• Languages: English
• ISSNs: 0964-1726

Abstract

Abstract: The model presented in this paper was shown to successfully account for cyclic loading effects and thermomechanical coupling in SMAs, including the influence of load rate and temperature on both the rate and value at saturation of the residual strain. It is the first such comprehensive model to be successfully utilized for relatively complex simulations involving SMAs subjected to multiaxial nonproportional loading, which possibly result in strong stress gradients such as fracture mechanics. In fact, it is known that the high stress concentration at the tip of a crack in SMAs results in increased martensite transformation and reorientation, which influence the growth of the crack. The derivation of the constitutive equations as well as the time integration and relevant algorithmic considerations are presented in detail. The model was shown to allow reasonable agreement with several sets of reference experimental and simulation data taken from the literature.