Numerical Comparison Between Two Different Constitutive Models for Shape Memory Alloys
Marcello Almeida de Paula1; Alberto Paiva1; Darlene Souza da Silva Almeida1; Dionisio Jose Rodrigues da Costa1
1 Universidade Federal Fluminense
doi:10.20906/CPS/COB-2015-2464
Resumo
The constitutive modeling of the hysteretic behavior inherent to smart materials is a challenging task, no matter which scale is adopted. Concerning Shape Memory Alloys (SMA), there are a number of constitutive formulations, which are well-established in the literature and have been widely used by the research community. Nevertheless, each of them has its advantages and drawbacks, depending on the scope of application. Within this context, the main point is to provide the easiest model capable of describing the widest variety of phenomena. This work aims to compare two one-dimensional constitutive theories, highlighting that, despite of their simplicity, both of them are able to describe most of the thermomechanical behaviors exhibited by SMA and, thus, constitute suitable choices to simulate SMA smart structures applications. The first constitutive theory considers the "assumed transformation kinetics" approach, whereas the second one is based upon internal restrictions. Numerical simulations are performed in order to demonstrate the capability of both models to describe pseudoelastic behavior at different temperatures, shape memory effect and temperature-induced phase transformation, besides their subloops due to incomplete phase transformations, for both tensile and compressive behavior. At last, a critical discussion is conducted to elucidate some discrepancies between the two models.
Palavras-chave: Shape Memory Alloy; Constitutive Model; Numerical Simulation