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Shape memory alloys (SMA) have a unique behavior due to a reversible phase transformation between two solid crystalline structures: martensite (low temperature and low stiffness phase) and austenite (high temperature and a higher stiffness phase). This transformation can occur either as a result of temperature change or mechanical stress load, both above characteristic critical values of these materials. Due to the reversible nature of this phenomenon, direct transformation occurs when austenite transforms into martensite and reverse transformation when martensite transforms into austenite. The latter is induced by raising the temperature and it is this process that occurs during the generation of significant associated forces through the undergone deformation recovering of the material, being of fundamental importance for the use as actuators.