Equivalent linear stiffness and damping of a shape memory alloy bar operating at isothermal and non-isothermal condition:

Complex stiffness of shape memory alloy bar is evaluated for isothermal and non-isothermal operating conditions. Analytical, numerical, and graphical approaches are used to evaluate complex stiffness. Real part of complex stiffness provides a measure of storage modulus, while imaginary part provides that of loss modulus. Complex stiffness is described as a function of forcing amplitude. Thermomechanical coupling changes the complex stiffness of the shape memory alloy bar at different operating conditions. It even becomes a function of forcing frequency during non-isothermal operation.