Ni2MnGa alloy belongs to a new group of materials, which attracts the attention of researchers as a ferromagnetic shape memory alloy. Ferromagnetic shape memory alloys are different from conventional shape memory alloys so that they can exhibit the shape memory effect in attendance magnetic field. Researches indicates that martensitic transformational temperature is strongly dependent on the percentage of the initial constitute components. If the percentage of Ni element increases (within the limit of the crystal structure), the transition phase, TM, will be changed from 180K up to 450K. Structural and magnetical phase transition temperature have an important role in description of application of shape memory alloys. In this paper the structural properties of the shape memory alloy, Ni2MnGa, and its magnetic characteristics at room temperature were investigated by a vibration sample magnetometer with maximum applied magnetic field of 2000 Oe. We prepared our samples by using an arc melting method. Also we studied the Magnetic susceptibility of the sample in temperature range of 100-300 K. We took advantage of x-ray diffraction analysis to determine the actual structure of Ni2MnGa target sample. The result of EDX indicated that the sample composition is Ni49.7Mn26.6Ga23.7 which is almost close to the desired alloy structure (Ni2MnGa) at room temperature. This sample has L2 cubical structure with lattice constant of 5.88 A. By measuring the alternative magnetic susceptibility in terms of temperature, we obtained TM=215 K for transformation temperature from martensite to austenite phase. By measuring the alternative magnetic susceptibility in terms of temperature, we obtained TM=215 K for transformation temperature from martensite to austenite phase and also the pre martensit unstable phase transition was found to be at 258K. The result of magnetic susceptibility shows that this alloy exhibit ferromagnetic behavior above the martensitic transformational temperature (TM) and paramagnetic below this temperature. The result of VSM indicates that at room temperature the sample is soft ferromagnetic with magnetic saturation value of 80.60 emu/gr. Applications of these materials will be extensively tested in laboratory conditions. High precision required for synthesis of these materials demands their evaluation before use in testing applications. Test results presented in this study provide a solid basis for future magnetic and physical properties evaluation efforts.

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