Mathematical model and experimental verification of shape memory alloy for designing micro actuator

An advanced mathematical model of a shape memory alloy (SMA) useful for designing SMA micro-devices is proposed and applied to coil spring theory to analyze the appropriate mechanical and electrical characteristics. This model can handle three phases of the SMA: the parent phase, the martensitic phase, and the R-phase. of three steps. First, the mechanical properties of the three phases are modeled at the solid mechanics level. Second, a model of thermoelectric transformation is obtained at the thermodynamic level. Finally, the first and second steps are combined. The model was applied to coil spring theory and was verified successfully by experiments under general conditions