An influence of the maximum thermal cycle temperature on a value and temperatures of the two-way shape memory effect (TWSME) was studied in Ti50Ni50 alloy subjected to a preliminary deformation by two ways: through isothermal deformation up to 12 % in martensite state or via cooling and heating under a constant stress of 80 MPa. Additionally the samples were subjected to one or ten thermal cycles within the temperature range of 440 – 300 K to change the dislocation structure formed during preliminary deformation. It was found that values of the TWSME and martensitic transformation temperatures varied in three temperature ranges on an increase in maximum thermal cycle temperature. It was shown that in the first temperature range from 440 to 490 K a variation in TWSME parameters was observed in the samples which were not subjected to preliminary 10 thermal cycles. In the second temperature range from 490 K to 610 K a redistribution of the dislocations resulted in a decrease in a value of TWSME with a low rate and hardly increase in Ms temperature. In the third temperature range from 610 K to 700K a recrystallization led to a significant decrease in a value of TWSME and a strong increase in Ms temperature.
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- Materials Science(all)