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The paper describes the growth features of thin Ti-Zr-Ni films prepared by the method of magnetron sputtering of the targets with compositions Ti53Zr30Ni18 and Ti41Zr38.3Ni20.7 on the substrates at 300 K with subsequent annealing in vacuum. The formation peculiarities of phase composition, structure and thermal stability of quasicrystalline thin films were studied. It was established that in initial state the films were X-ray-amorphous or nanocrystalline with coherence lengths (according to Scherrer) near 1.6-1.8 nm independently on the element composition of the sputtered target. This structure is relatively stable up to the temperature 673 K when the formation of the quasi-crystalline phase begins. In the films with composition of Ti53Zr30Ni18, the largest quantity of the quasicrystalline phase with a characteristic parameter aq  0.517 nm is observed at the annealing temperature of 673 K. It is added with an admixture of the 1/1 W-crystal approximant phase. In the films with Ti41Zr38.3Ni20.7 composition, an optimal annealing temperature is between 823 K and 873 K. The quasicrystalline phase is characterized by the quasicrystallinity parameter aq  0.5205 nm. Additionally, for the first time, the data on the formation of 2/1 approximant crystal as an admixture phase in this system were obtained. Under annealing at the temperatures higher than 873 K, the decomposition of the quasi-crystalline and approximant phases into crystalline phases stable at higher temperatures according to the equilibrium phase diagram was established.

In the work, we studied the regularities and mechanisms of microstructure formation in binary TiNi alloys with 50.2 and 50.8 at.% Ni under warm abc pressing with a stepped decrease in strain temperature (873, 673, 623, and 573 К) and isothermal (723 К) multipass caliber rolling. In the TiNi alloy with 50.2 at.% Ni at all abc pressing stages, microstructures inhomogeneous in grain size were formed due to faster dynamic recrystallization and hence faster formation of finer grains and subgrains in strain localization bands compared to microvolumes bounded by these bands. After final abs pressing at 573 К with a total true strain е = 7.7, a microstructure composed of submicroand nanocrystalline grains and subgrains was found. In the TiNi alloy with 50.8 at. % Ni subjected to warm rolling, three stages of grain structure evolution were revealed. At the first stage with low strains, the average grain size ‹d› increased due to collective dynamic recrystallization. At the second and third rolling stage, the average grain size ‹d› decreased steeply due to discontinuous and continuous dynamic recrystallization. On rolling at е = 2.0, a microstructure composed of microand submicrocrystalline grains was formed. An algorithm was proposed for estimating the critical strain for the onset of dynamic recrystallization from dependences of grain sizes on true strain. The sequences and temperatures of martensite transformations from a cubic В2 phase to rhombohedral R and monoclinic В19′ martensite phases were studied depending on the strain accumulated in abc pressing and rolling.

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