Effect of the Conditions of Crystallization of Rapidly Quenched TiNiCu Amorphous Alloys with High Copper Contents on the Characteristics of Martensite Transformations and Shape Memory Effect

Resumo

Amorphous TiNiCu alloys with copper contents of 28 to 38 at % are fabricated via melt spinning. The isothermal crystallization of alloys is conducted at 500°C with variable durations of the heat treatment (100 to 300 s). It is shown that shortening the duration of crystallization prevents the formation of brittle phases of the Ti–Cu system and contributes to the martensitic B2 ↔ B19 transformation, with the temperature intervals of transformation shifting to higher values and a marked increase in the enthalpy of the martensitic transitions and the magnitude of the shape memory effect.