الفهرس 
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Abstract
Smart materials have the ability to respond to external stimuli. These materials get use in many fields, and applications acting as sensors, or actuators. Shape memory alloys are a type of smart materials. They are programmed to memorize original trained shape. Nickel, manganese, and gallium (Ni-Mn-Ga) is one of ferromagnetic shape memory alloys. They can give large output strain at high frequencies. This work presents a study of producing polycrystal ferromagnetic shape memory alloy, and investigating magnetic properties of a thermally treated alloy which was trained by means of a new method of training by applying different hydrostatic pressures to the alloy. Single near stoichiometric composition was produced by means of two alternatives; the first is induction furnace, and the second is arc furnace. Elemental analysis showed homogeneity of the alloy produced by the arc method while induction sample had some impurities and non-homogeneous composition. So induction sample was eliminated, and arc sample is used for this study. XRD pattern revealed Martensitic phase peaks. Transformation temperature was found to be below 100 OC for the thermally treated sample. Training was applied by the hydrostatic pressing die. Different training pressures were applied using a universal testing machine. After applying hydrostatic pressures starting from 2.5 bar to 10 bar, it was found that pressures up to 7.5 bar will increase the coercivity, and saturation magnetization of the alloy, while loads beyond 7.5 bar lessened these magnetic properties. Hardness values for all trained samples were convergent which mean that neither thermal treating process nor training makes any effect on the hardness of the alloy.