Phenomenological analysis of thermal hysteresis in Ni-Mn-Ga Heusler alloys |
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Authors: | M. A. Zagrebin V. V. Sokolovskiy V. D. Buchelnikov |
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Affiliation: | 1. Chelyabinsk State University, Chelyabinsk, Russia;2. National Research South Ural State University, Chelyabinsk, Russia;3. National University of Science and Technology “MIS&4. S”, Moscow, Russia |
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Abstract: | The manipulation of thermal hysteresis in Ni-Mn-Ga Heusler alloys with coupled magnetostructural phase transition is studied theoretically using the Landau theory, including magnetic, elastic and crystal lattice modulation order parameters as well as an external magnetic field. It is shown that for the assigned combination of phenomenological parameters, in the phase diagrams, the Austenite–Martensite first-order phase transition has a finite (critical) point in which the thermal hysteresis is disappeared. Moreover, this point depends on the relation between modulation and elastic constants as well as on the magnetic field. Obtained results have been compared with other theoretical end experimental data. |
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Keywords: | Heusler alloys Landau theory phase transitions critical point hysteresis |
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