In this work a 1-D constitutive model for high temperature shape memory alloys (HTSMA's) is presented, where the range of operating temperatures allows the appearance of creep mechanisms during transformation. The model aims to capture the coupled phenomenon, where the rate independent transformation and the rate dependent viscoplastic behavior coexist. Based on continuum thermodynamics, the Gibbs free energy and the evolution equations for forward, reverse transformation and creep are properly chosen. The generation of time independent irrecoverable strains during transformation is also taken into account. The calibration and validation of the model in the 1-D case is achieved with the help of experimental tests in Ti₅₀Pd₄₀Ni₁₀, including isobaric tests at selected stress levels with 2 different temperature rates.

Date Published: 31 March 2009
PDF: 7 pages
Proc. SPIE 7289, Behavior and Mechanics of Multifunctional Materials and Composites 2009, 72890U (31 March 2009); doi: 10.1117/12.817689

Published in SPIE Proceedings Vol. 7289:
Behavior and Mechanics of Multifunctional Materials and Composites 2009
Zoubeida Ounaies; Jiangyu Li, Editor(s)