International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Thin coatings of aluminum oxide (Al2O3), zirconium oxide (ZrO2) and samarium oxide (Sm2O3) on aluminum alloy Al7SiMg (A356) were prepared by sol-gel method and immersion technique. The materials were characterized in detail by X-ray diffraction. The luminescent properties at room temperature were also investigated. Luminescence analysis showed that the Al2O3 coating containing ZrO2 exhibits broad excitation and emission bands, peaking at 328 nm and 392 nm, respectively. Photoluminescence data for the Al2O3 coating containing ZrO2 and Sm2O3 indicated effective excitation at 404 nm and strong broadband emission, which is due to the co-emission of ZrO2 and Sm2O3. Chromaticity coordinate analysis revealed that Al2O3 coating containing ZrO2 and Al2O3 coating containing ZrO2 and Sm₂ O₃ emit in the blue-purple and pale pink regions, respectively.The chromaticity coordinates, color purity and CIE (Commission Internationale de L’Eclairage) color-correlated temperature were determined.

The latest version of MAGMASOFT software package – MAGMA6.1 is used to simulate and optimize a casting formation. The alloy AlSi7Mg was used for this purpose. The casting is intended for the production of a wire connector for high voltage power transmission networks. Die casting method is used. The results obtained from the stimulation of pouring and crystallization of the casting are presented. Based on the located defects and the analysis performed, changes of the technology were made, which ultimately ensure the formation of a defect-free and soundness casting.

This paper presents a methodology and an application presented by the authors in previous publications. The application is integrated into SolidWorks and it’s used to automate the design process of modular fixturing devices. Included in it is a methodology for automated determination of the positions of the clamping elements. Both the application and the methodology are using rule-based logic and mathematical formulas.

A summary study of the development of solar energy and the main factors determining the productivity of photovoltaic systems has been carried out. The predominant surface contaminants of solar panels, reducing the efficiency of photovoltaic installations, and the existing different design types of cleaning systems for their effective removal are examined. The main trends in the development of singlelayer and multi-layer hydrophobic and other oxide coatings with diverse performance indicators suitable for solar panels are traced. In laboratory conditions, experimental self-cleaning coatings (based on compositions with the participation of Y2O3 and ZrO2) deposited by the sol-gel method on vitreous samples were obtained. The structure and morphology of the prepared thin films and the technological conditions for the deposition of nanoscale layers with different functional characteristics were investigated. The experimental results represent a prerequisite for the development of a series of additional compositions and a detailed technological regime for obtaining various modifications of resistant, long-lasting self-cleaning coatings, potentially applicable to photovoltaic panels.

Thin films deposited on glass substrates by sol-gel containing ZrO2 show photocatalytic activity, which are compared with TiO2 – which is used as a standard photocatalytic material applied in photovoltaics. By modifying ZrO2, coatings on glass surfaces were obtained, which are characterized by high properties, which are a prerequisite for use in photovoltaics. The coatings are dense and nanocrystal line according to SEM and XRD studies and optically transparent according to UV-VIS-NIR spectra

A methodology has been developed for obtaining of porous castings from Al and aluminum A356 alloy. The methodology includes introduction of Ca into the melt for viscosity increasing and homogenization by mechanical stirring. This is followed by addition of TiH2, homogenization, subsequent formation of the porous structure and crystallization. Tests were carried out on specimens of the castings involving abrasive wearing under dry friction conditions on a surface with hard-attached abrasive particles.

An analysis of the prospects for the development of FDM printing technology has been carried out. The paper studies the possibility of obtaining polymer products based on polyamide 6 and its compositions by layer-by-layer deposition. Tests of the strength indicators of the printed experimental products were carried out. The mechanism of the influence of the composition and modes of formation of printed products on their strength characteristics is proposed. The influence of the composition of the composite polymer material based on PA6 on the quality of printing products has been studied. Methods for controlling the shrinkage parameters of products obtained by
layer-by-layer deposition are proposed. The obtained results of the study can be used in the development of composites for the production of polymer filament to ensure the process of FDM printing of polymer products, including for the needs of mechanical engineering.

The object of research – the natural glycoalkaloid solanine as a possible inhibitor of acid corrosion of steel St3. Modern data on the structure and physico-chemical properties of solanine, such as amphiphilicity, surface activity, basicity, characteristic of modern organic corrosion inhibitors, are presented. The basic concepts are defined: basic nitrogen, solanine amphiphilicity, mass and volume corrosion indicators, corrosion inhibitor, degree of protection, corrosion inhibition coefficient. The literature data on the corrosive activity of lactic acid (MC) are presented and characterized.

Four types of aluminium alloys (two casting and two plastically deformable) were used in the present study. A special press mould for compacting the aluminium alloy chips and subsequent extrusion of the resulting compacts was designed and manufactured. The compressive strength of the obtained samples was investigated, in relation to their chemical composition and technological parameters during their fabrication. The results of the research are presented in tabular and graphic form. It was established that compacted samples from AW-6082, AC-48000 and AW-2024 alloy possess high compression strength (in the range of 766 – 866 MPa) under compression loading at 60% deformation. It seems that the extrusion process improves compression properties of AW-2024 and AC-48000 alloy but has negative effect on AW-6082 and AC-42000.

Technological first-order phase transition is obtain base process of material science by numerical experiments at use of finite elements method (FEM). The history of movement and the geometry of the front in the first-order phase transition are investigated. A free first-order phase transition was investigated to estimate the local place of the liquid residue. Mathematical model is Stefan-Schwartz task in 3D case. The corresponding temperature fields of a free and technological first-order phase transition are presented. Engineering information is local phase transition conditions is shown of macro-level with the local transition time and volume at the front is assumed.