In the last decades, smart materials especially Shape Memory Alloys (SMA’s) have attracted special attention as these materials can make an appropriate solution for the most of engineering problems. Nowadays, SMA’s are widely used in many engineering fields including: biomechanics, aerospace, civil and robotics applications. One of the most important applications of SMA’s is in the field of actuators. For predicting the SMA actuators, an appropriate model that can consider all of the SMA’s complexities is needed. Firstly, a 1-D Electro-Thermo-Mechanical model is proposed for actuator applications. This model, within the continuum mechanics framework, can predict shape memory effect, pseudoelacticity, strain rate dependency and longitudinal variation of parameters. The problems considered in the previous works for complicated thermomechanical paths are solved in this model. The proposed model is evaluated in 4 common conditions in SMA actuators. Then, the effective factors in the time response of SMA actuators are investigated. Results show that the supposed model of free convective heat transfer has a great effect in the final response and that considering the convective heat transfer coefficient as a constant number, may not be a good assumption. Comparing to equations obtained by energy balance, deriving the governing equations in the continuum mechanics framework would lead to obtain some additional expressions. Results show that neglecting these terms can lead to a wrong prediction for SMA actuators. The second part corresponds to experimental works. Because of the complexities existing in the behavior of shape memory alloys, prediction of SMA response needs several material parameters which should be obtained by accurate tests. Firstly, a proper procedure to access transformation temperatures is suggested. Secondly, a thermal chamber is designed and manufactured for performing different thermomechanical tests. This chamber can be mounted on different tensile tests machines and can be used for carrying out mechanical tests in the specified temperatures. By performing several thermomechanical tests, the necessary parameters for the proposed model are extracted for the both NiTi samples. Keywords: Shape memory alloy, Electro-Thermo-Mechanical model, SMA actuators, DSC tests, Thermal chamber, Thrermo-Mechanical tests,