Shape memory alloys (SMAs)have enormous potential for a wide variety of applications. Therefore there has been a wide concern for studying the properties of those alloys. In this study polycrystalline alloys from shape memory alloy have been prepared successfully by thermal plasma spray in a wire form of 3mm diameter in a graphite cast with three different ratios Ni5oTi5o, Ni5o.5Ti49.5 and Ni51Ti49 . Its structure has been tested by means of (X-ray) diffraction technique The samples of (X-ray) have showed that its structure in the room temperature is a mixture of austenite and martensite phases . It has been noticed that annealing at 500° C helps to transform part of the material from an austenite phase into a martensite phase .It has also been noticed that increasing Ni proportion more than 50% to Ti in the alloy increases the martensite phase . Calculating the temperature of phase transformation as a function to the temperature of NiTi is done by using Differential Scanning Calorimeter (DSC)at a temperature between 100°C and -80.0°C in a scan rate of 10°C/min . The charts show that transformation from an austenite phase into martensite phase is done through an intermediate phase called (R-phase )which means there is no direct transformation , while transformation from martensite into austenite in heating cycle is direct . An exception to that is annealing Ni5oTi5o at a temperature of 400°Cwhere the transformation cycle is in two stages. A training process for NiTi wire has been done to programme shape memory alloys where they are reversed in the direction of heating and cooling cycle that is from one-way memory effect into two-way memory effect. The mechanical properties for the wire of shape memory alloy which include tension test and measuring the amount of elongation in a stable temperature have also been studied . To test the ability of using NiTi in the medical filed to get benefite of its physical properties, the biological influnces on the bone tissues have been studied as well.