With the development of technology, the demand for "smart" materials, capable of actively respond to external influence (temperature or magnetic field, etc.) and even doing some work, has been increasing. These materials also include shape memory alloys, which remember how they were shaped before we deformed them and, when heated or cooled, will return to their original form without the use of external forces. The condition for the formation of shape memory effect is the crystallographically reversible martensitic - austenitic transformation, that can be followed by measuring the start and end temperatures of the transformation during cooling (Ms and Mf) or heating (As, Af).
In the diploma work, we studied the influence of thermal cycling on the change of the characteristic temperatures of the martensitic-austenitic transformation of Cu-Al-Mn alloy. Samples in the form of thin ribbons were produced by the melt spinning method. The change in the characteristic temperatures of the martensitic-austenitic transformation during thermal cycling was followed by accurate in-situ measurements of the change in electrical resistance. At the same time, we also monitored the change in the microstructure of the alloy by comparing and analyzing the microstructures of samples before and after thermal cycling. Characterization of the microstructure was performed by light and electron scanning microscope (SEM), equipped with the energy dispersive spectrometer (EDX).
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