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The corrosion-fatigue strength in 3 % aqueous NaCl solution and the resistance against hot salt corrosion (HSC) of the fine-grained near-α alloy Ti-5Al-2V (Russian analogue of Grade 9 titanium alloy with increased aluminium content) have been studied. The properties of the Ti-5Al-2V alloy in the coarse-grained state, in the fine-grained state after cold Rotary Swaging (RS), in the partly recrystallized state and in the fully recrystallized state have been investigated. The mechanical properties of the alloy were characterised using compression tests and microhardness measurements. The effects of RS, the annealing temperature, the time on the characteristics of corrosion destruction of the surface and the composition of the products of the HSC were studied. RS was shown to increase the depth of the intergranular corrosion defects, whereas recrystallization annealing promoted an increase in the corrosion resistance of the Ti-5Al-2V titanium alloy. The parameters of the Basquin equation for the corrosion-fatigue curves for the near-α Ti-5Al-2V alloy in the coarse-grained state, in the severely strained state and after recrystallization annealing were determined for the first time. An effect of non-monotonous dependencies of the slopes of the corrosion-fatigue curves for the strained near-α Ti-5Al-2V alloy on the recrystallization annealing temperature has been observed. • The corrosion resistance of the Ti-5Al-2V alloy depends on the presence of β-particles and the V-rich grain boundaries • Cold Rotary Swaging (RS) leads to an increase in the strength, hardness and corrosion-fatigue strength of the Ti alloy • RS results in a reduction in the corrosion resistance of the titanium alloy Ti-5Al-2V • Recrystallization annealing improves in the resistance to intergranular hat salt corrosion • Recrystallization annealing leads to a non-monotonic change in the slope of the corrosion-fatigue curve σ а (N) [ABSTRACT FROM AUTHOR]

Proposes a model for calculating the minimum grain size that can be obtained by the method of equal-channel angular pressing. Experimental and theoretical results; Expressions obtained describing the grain refining limit as a function of material properties and temperature of intense plastic deformation.

This paper presents the results of studying the thermal stability of the grain structure, mechanical properties, and specific electrical resistivity of the Al-0.5 wt%Mg- x Sc ultrafine-grained (UFG) alloys with varying scandium content (x = 0, 0.2, 0.3, 0.4, and 0.5 wt.%). The alloys were produced by induction casting and Equal-Channel Angular Pressing (ECAP). The alloys with Sc concentration above 0.3 wt% contained submicron Al 3 Sc primary particles, the amount of which increased with increasing Sc concentration. The decomposition kinetics of the Al–Sc solid solution in the UFG alloys was determined by the diffusion intensity along the dislocation cores in the lattice as well as at the grain boundaries. High thermal stability of the UFG structure in the alloys was ensured by ECAP at 225 оC whereas the recrystallization onset temperature was 375 оC. The UFG alloys exhibited high plasticity at the room and elevated temperatures and good combination of strength and electrical conductivity. • Al-0.5%Mg-(0–0.5)%Sc ultrafine-grained (UFG) alloys were obtained by ECAP. • The recrystallization temperature in the UFG alloys was found to be 375 оC. • The Al 3 Sc particles nucleate via the grain boundaries at lower temperatures. • The Al 3 Sc particles nucleate via the lattice dislocation cores at higher temperatures. • The UFG alloys exhibited high strength, good plasticity and electrical conductivity. [ABSTRACT FROM AUTHOR]

• A technique of microcumulative testing without the use of explosives was developed. • The microjet flow speed equals the speed calculated according to the hydrodynamic theory. • The efficiency of this technique was demonstrated using high-purity copper as an example. • The microjet penetration depth into a steel depends on the microstructural parameters of copper. A novel experimental laboratory technique for evaluating the ultimate dynamic plasticity of materials, under the conditions of cumulative jet flow and without using explosives, is described. To perform the microcumulative tests, miniature cylindrical specimens with conical pits were used. The dynamic loading of the specimens was performed using a gas gun with a striker accelerated up to speeds in the range of 600–800 m/s. The optimal specimen geometry and testing regimes, including the focal distance during microcumulation testing, were then determined. The flow speed of the microcumulative jet was found to be equal to its theoretical value calculated within the framework of the Lavrent'ev hydrodynamic theory. The novel technique was demonstrated to enable the study of the relationship between the initial specimen microstructure and the ultimate dynamic plasticity magnitude at the cumulative jet flow using high-purity copper as an example. The penetration depth of the cumulative microjet into a steel barrier was shown to depend on the parameters of the copper microstructure. A preliminary analysis of the effects of copper purity and processing regimes on the ultimate dynamic plasticity characteristics was performed. [Display omitted]. High-speed filming of the cumulative microjet. The head element of the CJ is marked by the blue dashed line. The time gap between (a) and (b) frames was 16 μs. [ABSTRACT FROM AUTHOR]

Highlights: [•] High density ceramics with NZP structure were prepared by Spark Plasma Sintering. [•] Ceramic materials were irradiated in cyclotron by Xe ions with fluences 6×1010 to 1×1013 ions/cm2. [•] The conditions of transformation from metamict to crystalline state have been found. [ABSTRACT FROM AUTHOR]