Shape memory alloys (also referred to as smart materials ,intelligent materials ,adaptive materials) are materials which have increasing range of engineering , aerospace, and biomedical applications. Smart materials can act as transducers and physical parameters converters. Some of them can convert energy from one form into another such as mechanical energy (stress) into a change in length (strain) or electrical energy (supplied electric field) to electric displacement. Others convert the thermal energy (change in temperature) into a change in entropy and the magnetic energy (supplied magnetic field ) to a magnetic flux. The chemical energy (change in concentration) may also be converted into a volumetric flux by SMA's. Smart materials undergo solid to solid phase transformations from Austenite to Martensite Mostly Austenite has cubic lattice structure while Martensite phases have lower symmetries which may be (trigonal, tetragonal, orthorhombic , or monoclinic ) lattice structure.