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The effect of gamma irradiation on the optical band gap of polyimide film and its composites with a filler of finely dispersed powder of high-temperature superconductor (HTSC) YBa2Cu3O6.7 with concentrations of 0.05% by weight; 0.1% by weight; 0.5% by weight was studied. Optical properties were studied in the spectral range of 190-1100 nm using a Shimadzu UV-3600 spectrophotometer. Based on optical absorption spectra and optical band gap calculations for the composite system, we find that the optical band gap (Eg)...

We studied polyimide and lavsan films after exposure to varying doses of electron irradiation, mechanical loading, and temperature. It was found that at the first stage of mechanical loading, up to 1 MPa. A similar sharp increase in the relative elongation of the films by 3% was observed. This is due to the rotation of globules and the straightening of macromolecular chains in the material along the direction of the applied load. The dependence of the absorption coefficient on the wavelength per unit path length i...

It is shown that the corrosion-electrochemical behavior of coatings with iron (cobalt) tungsten alloys depends on the content of the refractory component, and the increase in chemical resistance in an acidic medium is due to the formation of acidic tungsten oxides on the surface. The use of artificial neural networks allowed us to identify the most significant parameters that determine the corrosion resistance of alloys. Electrolysis was carried out in a glass cell for a two-electrode scheme using planar positione...

The process of mixed oxide coatings forming on a high-silicon aluminum alloy in the cobalt-containing pyrophosphate electrolyte by the plasma-electrolytic oxidizing (PEO) method is studied. It was shown that AL25 chemical composition heterogeneity causes the consumption of part of the anode current to homogenize the treated surface, which is reflected in minimizing the content of doping components at the initial processing stage. It was established the growth of mixed oxides Al2O3·CoxOy relative mass to be a funct...

The structure and the properties of the oxide nano-composition coatings formed on titanium in the diphosphate based electrolytes by means of plasma electrolytic oxidation in the spark-discharge regime at application of interelectrode voltage 100 to 130 V have been studied. The possibility to obtain the oxide layers containing the alloying elements by the modification of the composition of electrolytes has been stated. The chemical and phase composition as well as the topography, the microstructure and the grain si...

The aim of the present work is to develop, substantiate, and study a fundamentally new method of derivation of composite electrolytic films making it possible to control their composition and structure. We assume that, after the termination of the stirring-up of a bath containing the electrolyte-suspension with monodisperse spherical particles of the same density, a uniform sedimentation space is established. The upper boundary of this field will descend with a velocity depending on the dispersity and density of a...

Engineering novel material structures has continually been pursued to further advance modern technologies. These advancements often rely on novel processing technologies. Although many processing parameters have been thoroughly examined in the field of composition coatings, the formation processes are an exception. In this work, we examine the unique microstructures of composite electrolytic coatings, obtaining from electrolytes-suspension which contains nano-size particles of SiO2 and carbon. Metallographic resea...

The main aim of the work is theoretical and experimental research of nanocomposite systems formation process on the model of chromium electrolytic coatings, ascertainment of laws and mechanis ms of silicon dioxide nano-sized particles influence on the structure and properties of metal. We researched the process of electrolytic formation of chrome - silicon dioxide nanocomposite systems and nanostructured composite electrolytic coatings with silicon dioxide (3-50 nm) used as a dispersed phase. Methods of the resear...