Section of Mechanical and physical properties of materials

Nanostructured NiTi and its tensile behaviour.

The thermokinetics of shape recovery after bending of Ni-rich titanium nickelide was studied. Loading–unloading procedure was carried out in various phase states using isothermal and non-isothermal modes varying loading strain. The two-stage character of shape recovery under heating is revealed; the hypothesis of its origin is suggested.

Possibility of using silver nanoparticles (Ag NPs) as additive for silicone elastomers as internal heating agent for microwave radiation assisted local curing is experimentally investigated. The obtained PDMS/AgNP composite materials acquired a significantly higher work of adhesion to glass, a lower viscoelastic modulus and slightly higher wettability. With time of microwave treatment and consequently cross-linking of the material those parameters head towards or approach those of the stock PDMS material.

Extensive hydrogen desorption, which is continued and not ceased even after 24 hours after pre-exposure of ZK60 samples in the corrosion solution, is the evidence for the corrosion reaction occurring under the layer of corrosion products.

Protective coatings that improve the corrosion resistance of the E125 zirconium alloy under conditions of the combined effect of a hydrogen-containing medium and friction wear have been investigated.

Mechanical properties of Ti-6Al-4V three-layer material

The force change depending on the deflection during DWTT Curve No. 2 - the notch is perpendicular to the direction of vibration (WD); Curve No. 3 - the notch is parallel to the direction of vibration (WD). A characteristic feature of the deformation diagrams for specimens with the parallel notch is the presence of two local maxima. This contrasts with the force change curve for the perpendicular notch specimens.

Ductile-brittle transition behavior of medium-carbon steel with 0.32 %C-1,35 %Mn-0,003 %B by instrumented impact testing and fracture analysis was studied. On the load-displacement curves the periods corresponding to different zones of crack propagation are distinguished. Each period can be quantitatively described by a set of strength, plastic and gradient parameters.

Consolidation of detonation nanodiamond: effect of thermobaric sintering. The size increase in the nanodiamond core occurs through the growth of both the diamond phase and ordered graphite.

The microstructure, phase composition and mechanical properties of a low-carbon steel billet, obtained by the electron-beam additive manufacturing method using an industrial welding wire, have been studied.

Modeling the growth of a crack originating in the sample volume

Tensile machine and the results of the materials elastic modulus measurements and elongation at break

Thermal analysis (red curve, DSC) and the microhardness (HV) of nanostructured Invar 36 alloy (blue curve) as the function of the annealing temperature.

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

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.

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.

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

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.

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)

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.

The strain rate significantly influence on the functional properties of the NiTi alloy. In some cases, the shape recovery curves during thermocycling are completely different.

Preliminary deformation leads to an increase in the recovery stress only at a stiffness, at which the recovery stresses was close to the value of the yield stress in non-deformed specimens.

Median –0.0011, average –0.0010, max. 0.2135, min. –0.1775, standard deviation 0.0705.

Allocation of intermetallic phases in the material. Friction track and example of data recording of friction coefficient change.

Content increasing of nickel up to 20-25 % and molybdenum alloying, leads to a decrease of the peak strain values level during forging in the temperature range 900 - 1200 ° С at the 0,1 s-1 deformation rate

Fuel cells are the most efficient means to directly convert stored chemical energy to usable electrical energy. Doped ceria is considered to be a promising electrolyte for intermediate temperature operation.

It shows the wear behavior of three different orientations (a) Basal, (b) Prismatic, and (c) Pyramidal for the AZ91 magnesium alloy.

SEM images of obtained (co)polymers samples and installation for measuring of thin film sensors conductivity as a function of air humidity.

Magnetocaloric effect in as-cast Gd2In

Ni-14(Al, Ta)-30.7(Co, Cr, W, Hf) (wt.%) superalloy microstructure.

The paper emphasis on CNT-Al6065 Metal matrix composite for experimental investigations of mechanical and tribological behaviour. Surface modification on CNT were performed to avoid the agglomeration.

The value and relationship between the degree of elastic anisotropy and the Poisson's ratio of Ti-Ni alloy crystals are analyzed on the basis of our own and literature data obtained experimentally and computationally from the first principles. The elastic anisotropy of Ti-Ni crystals can be determined based on numerical differences in the extreme values of μ as Aµ = / µmax - µmin|/<μ>. A strong correlation was established between the elastic anisotropy coefficient A and the factor Aµ (the correlation coefficient 0.9871).

The influence of the annealing atmosphere on the electrical conductivity and thermo-EMF of strontium orthocuprate (Sr2CuO3) at temperatures up to 150°C has been investigated. It was shown that during heat treatment in hydrogen or in an atmosphere saturated with water vapor at temperatures above 70°C ionic current carriers appear in Sr2CuO3.

The selectivity of shear systems during microindentation of single crystals of Hadfield steel by a Vickers pyramid is shown in accordance with the calculated value of the Schmid factor for slip systems.

The results of experimental studies of the electronic conductivity, Seebeck coefficient and thermal conductivity of the superionic KxCu2-xS (x = 0.1, 0.2, 0.25) alloys in the temperature range from 30 to 420 ° C are presented and discussed.

The value of thermokinetic EMF in equiatomic titanium nickelide depends on a preliminary deformation.

The electrical supply was applied to induce an electrical field to the titanium samples, and their microhardness and elastic modulus were measured. The microhardness raised by 11% from 0 V to 1 V, and the elastic modulus increased three times.

Impact loading diagrams of layered samples

A straight-line section of the kinetic diagrams of the fatigue fracture of the Mg6Al magnesium alloy after annealing (white dots) and after ECAP (black dots). The test samples were carried out at loads of 800 and 1000 N.

We obtain a decreasing of hardness with increasing the fracture toughness of Mo2NiB2 - Ni cermets because of the formation of Mo10Ni3C3B phase. A comparative analysis of electronic structure showed relatively low hardness as well as higher plasticity of Mo10Ni3C3B compared to Mo2NiB2 boride due to more isotropic character of interatomic bonding.

The true stress-strain diagram of alloy E110 in the axial and tangential directions.

The fracture surface consisting of two parts featuring by low-temperature cleavage and hydrogen-assisted quasi-cleavage facets has been obtained. It is shown that the average misorientation angle of quasi-cleavage facets is 1.5 times lower than that of the cleavage ones.

The summary energy expenditures for deformation of specimens of pipe steel of strength class X80 were determined basing on experimentally measured geometry of the 3D images of fractured specimens.

The figure shows the true stresses versus the true strains of the Zr-1% Nb alloy under tension at high strain rates. The inhomogeneous fields of equivalent strains obtained by computer simulation of high velocity tension of specimens have good agreement with experimental data.

During bending, the distribution of deformation and microhardness is asymmetric.

Change in surface morphology as a result of irradiation of the surface with UV radiation

Structure and corrosion damage in a biologically active medium of a bioresorbable magnesium alloy

The fracture surface of the material with the formation of cracks in the volume of the sample

Timeline on transparent/translucent Sialon ceramics.