MATERIALS SCIENCE

V. A. Kryven

An exact analytical solution to the anti-plane problem of plastic strips quasi-static development on the extension of two arbitrarily distant cracks with the same length located on the same straight line is obtained. According to this solution the strips starting from a pair of inner tips develop to meet, and from the outer tips – in the opposite direction. The plasticity condi…

Ya. Ya. Sirak, V. M. Posuvailo, H. H. Veselivska, Yu. S. Shpuliar

The modern approaches to the formation of wear-resistant and bioactive coatings on titanium alloys by plasma electrolytic oxidation are summarized, the influence of electrolytes and additives on the coating properties is analyzed, and combined methods and prospects for biomedical applications are evaluated.

M. M. Student, I. M. Pohrelyuk, A. G. Luk’yanenko, O. Z. Student et al.

This study investigates the influence of surface modification of VT6 titanium alloy with interstitial elements (nitrogen and oxygen) on its tribological behavior under dry sliding conditions against a Cr18Ni10T steel counterbody. Tests were conducted at a specific load of 1 MPa for 600 s. Diffusion-hardened surface layers were produced by thermochemical treatment. Phase composi…

S. I. Gubenko

Abstract not available. Bibliographic information is searchable.

I. M. Dmytrakh, A. M. Syrotyuk, V. V. Ovsyanykov, R. L. Leshchak

Abstract not available. Bibliographic information is searchable.

M. M. Lopachak, L. M. Boichyshyn

Electrochemical behavior of as-cast and nanostructured alloys Co77Si11B12, Co72Fe5Si11B12, Co68Cr9Si11B12, and Co72Fe2,5Cr2,5Si11B12 in 1 M KOH solution was investigated. It was found that alloying with chromium shifts the corrosion potential to –0.43 V and increases the corrosion current density up to 1,03×10–2 mA/cm2. After annealing, the Cr-containing alloy exhibits a two-or…

M. R. Chuchman, V. R. Ivashkiv, M. S. Khoma, V. A. Vynar et al.

Abstract not available. Bibliographic information is searchable.

R. M. Yuzefovych, I. M. Javorskyj, Yu. I. Torba, Ye. V. Sbrodov et al.

Abstract not available. Bibliographic information is searchable.

O. M. Mokryy

Abstract not available. Bibliographic information is searchable.

A. G. Prygunova, S. S. Petrov, T. A. Aiupova, S. V. Prygunov

The effect of rapid cooling during melt deformation on the structure of hypereutectic Al–16.5% Si alloy, the elements of which are highly dispersed phases and primary silicon crystals of specific morphology, is studied. Under the synergistic action of local melt deformation and high cooling rates, the mechanism of crystal nucleation and growth changes. During eutectic decomposi…

I. B. Ivasenko, O. R. Berehulyak, R. A. Vorobel, T. I. Voronyak et al.

An automated method for estimating the Poisson’s ratio using interferograms and speckle interferograms of the material surface by means of digital image processing was developed. Preliminary image processing based on a parameterized retinex was performed to equalize the background in preparation for further segmentation. Image segmentation was carried out using a threshold leve…

V. Z. Stankevych, O. M. Stankevych, M. O. Babyak

The stress-strain state of a two-layer composite containing a penny-shaped crack under the influence of SH-waves generated by time-harmonic torsional loads is investigated. The problem is solved using the boundary integral equation method, with the wave-field solutions represented through Helmholtz potentials. A system of boundary integral equations is derived to determine the …

M. B. Tymus, I. M. Zin, S. A. Korniy, V. I. Fedoriv

The corrosion behavior of St3 steel in weakly alkaline, chloride-containing solutions was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy, scanning electron microscopy, and energy-dispersive X‑ray microanalysis. These environments were inhibited by starch biopolymer and a composition based on it. The optimal content of starch + sodium glu…

V. M. Uchanin

A traditional procedure for determining the length of detected cracks using eddy current probe signals is analyzed, as are possible errors in determining the crack length associated with the scanning step and the sensitivity threshold level of the eddy current flaw detector. A perspective method for determining the length of cracks using characteristic points of the spatial dis…

M. M. Hvozdiuk, O. P. Maksymenko, Ye. V. Kharchenko, V. M. Paliukh

Abstract not available. Bibliographic information is searchable.

O. Ya. Chepil, I. M. Soviak, A. M. Syrotyuk

An analytical approach to evaluating the residual life Nfс of a defective pipeline element is proposed. The analytical approach considers the effects of the internal pressure (p) of a hydrogen-containing operating environment, defect geometry (axis ratio a/c), and the total hydrogen concentration in the metal (СH). Experimentally determined cyclic fracture resistance parameters…

V. P. Revenko, A. V. Revenko

Bodies with cylindrical and plane-parallel boundaries in the form of disks or rings are considered. To describe their three-dimensional stress state, the general solution of the Navier equations in the cylindrical coordinate system is used. After integrating the stresses over the thickness of the cylindrical plate, the normal and tangential forces are expressed in terms of one …

L. Yo. Onyshko, N. V. Zdolbitska, M. V. Delyavskyy, V. S. Kravets

The elastic equilibrium of thin iron-concrete plates resting on Winkler elastic foundation is investigated. Plates are considered as homogeneous and orthotropic ones with average Huber’s elastic modulus. The method for solving such plates is constructed. The procedure of generation of edge and surface nodes is suggested too. The method provides high accuracy and effectiveness o…

R. V. Horda, I. O. Polishko, Ye. M. Brodnkovskyi, D. M. Brodnikovskyi et al.

The electrolyte materials of solid oxide fuel cells, made of the developed 8YSZ powder and its analogue manufactured by Tosoh (Japan) were compared. It was found that under the same manufacturing conditions, ceramics from the developed powder demonstrated higher strength and ionic conductivity. Thus, samples sintered at 1400°C made from the developed and foreign powders, with a…

Xianghui Meng

Abstract not available. Bibliographic information is searchable.