Piecewise linear model of shape memory alloy and its damping characteristics
ZHENG Ji-zhou1； ZHANG Yan2
1.College of mechanical and electronic engineering, Shandong Agricultural University, Tai an 271018，China；2.College of information science and engineering, Shandong Agricultural University, Tai an 271018，China
Abstract：It is important to establish a simple and effective constitutive model of shape memory alloy (SMA) for engineering applications and theoretical analysis. The nonlinear constitutive relation between stress and strain of superelastic SMA was simplified and a piecewise linear one was derived with the effect of martensite content during the phase transition considered. Based on this model, expressions of loss factor and other characteristic parameters were given. Finally, the model was applied to a single degree-of-freedom system and the effects of shape memory alloy on vibration isolation were analyzed. The results of numerical simulation show that strain amplitude and temperature both affect these parameters with different degrees, and the stiffness of parallel spring has an influence on the damping effect of SMA wire.
2012, Vol. 31 
