Volume 11, Issue 3, September 2021

A successful attempt to incorporate knowledge obtained from severe plastic deformations into the AA5XXX series aluminum alloys treatment has been made. These advantages allowed revealing age hardenable mechanisms in non-age-hardenable alloy AA5XXX. All side investigation of structure and properties was made.

During fracture of high-pressure pipelines, the longitudinal crack can stop in one of two ways, which are discussed in the article.

Assessment of the performance of carbon Nano tube reinforcement in Nano composite coatings.

Prediction exactly of the failure zone in Lead rupture within the same non-homogeneous zone previously detected exactly using Scanning Contact Potentiometry technique,which was done in the elastic mode before conducting the tensile test.

Computer modeling of the pressure welding process of cylindrical workpieces from heterophase nickel-based superalloys through an interlayer was carried out.Two combinations of materials to be welded were considered: I – cylinders of the same wrought EP975 nickel-based superalloys in the initial coarse-grained state were welded through an interlayer of EP975 with a fine-grained microstructure; II – cylinders of different kinds nickel-based alloys, including wrought alloy EP975 in a coarse-grained state and intermetallic alloy VKNA-25 with a single-crystal structure, were welded through an interlayer of EP975 alloy with a fine-grained microstructure of the microduplex type. The distribution of equivalent, axial, radial, circumferential and shear components of stress and strain in the samples have been investigated. Analysis of the simulation results allows us to conclude that, in comparison to welding of the same name materials, when welding of different kinds materials, the radial, axial and circumferential stresses values increase. The maximum values area of shear stresses in the region of contact between the cylinders and the interlayer also increases. This factors combination allows us to conclude about more favorable pressure welding conditions for welding of different kinds alloys in comparison with the same name materials.

The microstructural images of superalloy subjected to different solid solution treatment obtained near the fracture zones of samples after creep tests at 850°C / 450 MPa.

The results of experiments on tension of the Ti-6Al-4V alloy in the range of strain rates from 0.1 to 1000 1 / s under uniaxial and complex stress states are presented. It was found that Ti-6Al-4V alloy exhibits a transition in fracture behavior from ductile to brittle at the stress state triaxiality parameter range from 0.44 to 0.497.

Diagrams «torque - twist angle» during torsion testing of samples of hot-rolled coarse-grained (1) and ultrafine-grained (2, 3) titanium Grade4 after ECAP conforms (2) and ECAP conforms + drawing (3)

In the work the possibility of obtaining promising layered metal-rubber composites based on low-carbon steels, aluminum alloy Al-Mg3 and heat-and-frost-resistant rubber by hot pressing is studied. The influence of the composition and design of composites on the impact strength at temperatures of 20 and -60 °C and the damping properties of materials determined by the method of dynamic mechanical analysis is discovered.

Cold rolling of Fe-17Cr-13Ni-3Mo-0.01C austenitic stainless steel leads to the formation of a fragmented structure with a high density of crystal structure defects. The main deformation mechanism during rolling is dislocation slip, which is accompanied by the development of mechanical twinning as an additional mechanism contributing to structure fragmentation. Saturation with hydrogen promotes more active development of twinning and the occurrence of the γ → ε phase transformation, and an increase in the current density upon saturation of the samples with hydrogen before rolling and a decrease in the deformation temperature is accompanied by an increase in the density of twin boundaries and the density of dislocations.

Confocal laser scanning microscopy technique allows high accuracy reconstruction of the corrosion damage topology, providing access to the assessment of the metal's volume loss and the corrosion rate

The characteristics of the stress-strain state determine the path and geometry of quasi-cleavage cracks in hydrogen-embrittled low-carbon steels.

Electric spark deposition of AISI 1045 in mixtures of iron granules with an amorphous CrMoWCBSi composition and the addition of WC powder makes it possible to form a composite coating of an amorphous matrix reinforced with tungsten carbide grains.

Structure of the high-entropy alloy irradiated by an electron beam with the energy density of 30 J/cm2. Temperature distribution on time throughout the depth for the energy density Es = 30 J/cm2.

Graphical abstract shows the electrochemical behaviour of nanocrystalline Ni, Ni90Cu10, Ni-TiN and Ni90Cu10-TiN thin films processed by reactive magnetron co-sputtering

A defective nanotube containing 5 and 8 -membered rings shows the highest adsorption capacity of 1.82 %wt/wt which is higher than the pristine nanotube and the adsorption capacity increases with %defect.

Modification of a microstructural model allows describing the strain variation on isothermal holding and predicting conditions (temperature and stress), at which the maximum of isothermal strain is attained.

The effect of the temperature of equal-channel angular pressing ranging from 0.45 to 0.75 Tm on the processes of grain refinement in the Al-3% Cu alloy was investigated. An increase in temperature led to increasing the average size of new grains, decreasing the average misorientation of intergranular boundaries, and shifted the formation of a fine-grained structure towards the higher strains.

The process of formation of a solitary wave under external harmonic action at the frequencies of the forbidden zone of the crystal.

Heat treatment at 700 ° C of commercially pure grade 4 - Grade 4 titanium results in the release of β-modification nanoparticles. The deformation of the material leads to an increase in the volume fraction of particles precipitated after annealing.

It was found that the electric pulse of low capacity leads to the development in the cryorolled pure aluminum of recovery and continuous recrystallization without hardness changes. Under threshold energy conditions there were found transition from in-situ recrystallization to grain growth, and sharp decrease in hardness.

Regulation of the corrosion rate of bioresorbable magnesium alloys through the use of vacuum zirconium coatings.

The oxide layer in the zone of solid-phase joint (SPJ) of ultrafine-grained titanium alloy VT6. The observed oxide layer reduces the shear strength of the SPJ by more than 2 times.