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The deformation behavior, microstructure, phase composition, and mechanical and functional properties of Ti-50.9 at.%Ni shape memory alloy during uniaxial compression in the temperature range from 25°C to 1000°C have been analyzed and are discussed herein. It was found that the deformation temperature of 300°C marked a boundary for the transition from the low-to hightemperature type of flow curves; achievement of the steady-state deformation stage was observed across a wide range of deformation temperatures. Following comprehensive analysis of the obtained data, the temperature ranges of the dynamic processes of recovery, polygonization, and recrystallization of the Ti-50.9 at.%Ni alloy were determined. Deformation in the range of dynamic polygonization is accompanied by not only the formation of B2austenite and R-phase, but also the precipitation of fine Ti 3 Ni 4 particles during deformational aging. The highest shape recovery characteristics were obtained after deformation of the Ti-50.9 at.%Ni alloy in the temperature range from 300°C to 600°C.

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In the present work, flow curves of an equiatomic Ti-Ni shape memory alloy after deformation by compression in the temperature range from 100 to 900 °C at a strain rate of 1 s -1 and up to a true strain (e) of 0.9 were obtained. The phase composition, mechanical and functional properties after compression to e = 0.5 were studied. The boundaries of the temperature ranges of the development of dynamic softening processes were determined, as follows: dynamic recovery in 100-300 °C range; dynamic polygonization in 300-500 °C range and dynamic recrystallization above 500 °C. An optimum deformation temperature range in terms of accumulation of high strains and achieving improved functional properties is 300-500 °C. It has also been found that post-deformation annealing at temperatures above the deformation temperature leads to the decrease in the B2-austenite lattice defectness and to a significant increase in shape recovery characteristics.

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The effect of rotary swaging on the microstructure, texture, and mechanical properties of the magnesium alloy Mg‐4.4Al‐0.9Zn‐0.4Mn is studied. Repetitive processing, conducted at progressively dropped deformation temperature (from 400 down to 200 °C), leads to an increase in the cumulative strain ε. Rotary swaging of the alloy is shown to lead to microstructure fragmentation due to intensive twinning on various crystallographic planes. A high density of twins observed at the final stage of deformation, at ε = 2.77, leads to a decrease in the distance between boundaries (including both twins and grain boundaries) to ≈3 μm. With decreasing temperature, 0.2‐μm‐wide secondary deformation twins form within the primary twins with a width in the range of 1.5–2.5 μm. The texture analysis shows that, upon deformation, the number of orientations increases as does their scatter. Rotary swaging at 350 °C to ε = 2.77 gives rise to an increase of both strength and tensile ductility of the alloy. The high strength characteristics are achieved due to the formation of a subgrain structure and profuse twinning. The increased tensile ductility is associated with the activation of prismatic slip in addition to developed basal slip.

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