A co-occurrence of magnetic and structural transitions was observed in a nonstoichiometric Ni 53 Mn 25 Ga 22 alloy which undergoes a reverse martensitic transformation from ferromagnetic martensite to paramagnetic austenite at a magnetic transition temperature (134 °C) higher than the Curie temperature of the stoichiometric Ni 2 MnGa alloy (103 °C). The effect of the magnetic field on the phase transition temperature was found to be two orders of magnitude greater in the present alloy than in Ni 2 MnGa due to the absence of the ferromagnetic state in austenite. This may open the possibility of utilizing NiMnGa alloys at a low magnetic field.
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