A thermomechanical model accounting for the behavior of shape memory alloys in finite deformations

Shape memory alloys (SMA) comport an interesting behavior. They can undertake large strains and then recover their undeformed shape by heating. In this context, one of the aspects that challenged many researchers was the development of a mathematical model to predict the behavior of a known SMA under real-life conditions, or finite strain. This paper is aimed at working out a finite strain mathematical model for a Ni–Ti SMA, under the superelastic experiment conditions and under uniaxial mechanical loading, based on the Zaki–Moumni 3D mathematical model developed under the small perturbations assumption. Within the current article, a comparison between experimental findings and calculated results is also investigated. The proposed finite strain mathematical model shows good agreement with experimental data.     

Existence and nonexistence results for quasilinear elliptic equations involving the <Emphasis Type="Italic">p</Emphasis>-Laplacian with a critical potential

This paper deals with the existence and nonexistence results for quasilinear elliptic equations of the form -_pu=f(x, u), where _p:=div(|u|^p-2u), p>1, and the solutions are understood in the sense of renormalized or, equivalently, entropy solutions. In particular we prove nonexistence results in the case f(x,u)=u^p|x|^-p, that is related to a classical Hardy inequality. Mathematics Subject Classification (2000) 35D05, 35D10, 35J20, 35J25, 35J70