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Effect of femtosecond laser processing on mechanical properties of plates made of submicrocrystalline VT1-0 titanium alloy is studied using active deformation and fatigue testing involving cantilever bending.

Differential scanning calorimetry has been used to study the effect of the temperature and holding time upon isothermal annealing on the calorimetric effects of the martensitic transformations (MTs) of an aging Ti–50.7 at % Ni alloy produced by hot helical rolling at a temperature of 850–900°С with subsequent cooling in air. The sequence of the phase transitions upon reverse MT has been determined using X-ray diffractometry. The regularities of the evolution of the characteristic temperatures of martensitic transformations after annealing at temperatures of 400, 430, and 450°С for 1–10 h have been analyzed. The results of electron-microscopic studies of the structure of the alloy in the initial state and after annealing have been presented; the features of the morphology of the Ti3Ni4 phase precipitated upon aging have been analyzed. Based on the results of calorimetric and structural studies, the temperature of the highest intensity of the aging processes has been determined.

Using warm, lengthwise grooved-roll processing of the Ti – 0.7 wt.% Si alloy, a nanostructured state is formed in it at 873 K with the grain-subgrain elements measuring about 280 nm. The titanium silicides precipitating during the dynamic strain-induced aging of the alloy are investigated by the methods of high-resolution scanning electron microscopy. It is found that the shape of the silicides is close to spherical, they have an FCClattice and an incoherent interface with the matrix.

We have experimentally studied the structure and phase variations in polycrystalline titanium stimulated by stepwise shock compression at pressures up to 40 GPa with subsequent unloading. The experiments were performed on samples of commercial titanium (VT1-0 grade) in a broad range of initial grain sizes (0.2–50 μm). The phenomenon of grain refinement and phase composition variation in titanium under stepwise shock-wave action has been studied by transmission and scanning electron microscopy techniques. Specific features of these changes are discussed.

A method of preparation of titanium materials with a porous surface layer by hydrostatic pressing and subsequent high-temperature sintering with use of a pore former as a temporary space holder was proposed. Comparative studies of the structure and properties of titanium materials with a porous surface layer fabricated in a new way and by the classical method of powder metallurgy (uniaxial pressing and high-temperature sintering) were carried out. It was shown that this method makes it possible to obtain porous titanium samples with preset parameters of pore space (volume fraction and pore size) and high mechanical properties. An experimental sample of an endoprosthesis element (acetabular cup) was fabricated using the proposed method.