Numerical thermomechanical modelling of shape memory alloy wires

The dynamic properties of straight shape memory alloy (SMA)-actuator wires are characterised by the rate of heating and cooling procedures. Based on an analysis of energy fluxes into and out of the actuator, a numerical model that simulates the time response of SMA-wires is presented. Cause variables that have an impact on the actuator behaviour (actuator geometry, provided load, arbitrary time variant heating current, environmental conditions) can easily be implemented in the model. Taking these changing boundary conditions into consideration, the model enables a simple design layout for technical solutions with straight SMA-wires.