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

The article investigates the influence of technology and technological parameters of manufacturing on the structure, phase composition and physical and mechanical properties of the Fe-FeCr800 composite system. It was established that the determining factor in phase and structure formation is the manufacturing technology, while vacuum sintering and hot forging have their own optimal technological parameters. At the same time, hot forging makes it possible to obtain a composite with a higher microhardness of structural components due to a change in the content of component components. The results of the research also showed that the preheating time (for 20 min.), as well as thermomechanical treatment, is sufficient for the phase formation process, in particular, with the release of carboboride phases of the type Me3CB and Me3(CB)2, while the densification processes are intensified, which makes it possible to obtain a material with lower residual porosity. Analysis of mechanical tests showed that vacuum sintering makes it possible to obtain composites with higher mechanical properties due to the active interaction between the components of the composite. However, high-temperature annealing after hot deformation will allow for a composite with high mechanical properties.

Aluminum alloys are critical in industries such as aerospace and automotive due to their lightweight, strength, and corrosion resistance. Optimizing their properties is challenging and benefits from advanced predictive tools. This paper explores the use of mathematical modeling in understanding and designing aluminum alloys. Techniques like thermodynamic modeling (e.g., CALPHAD), phase transformation kinetics, and mechanical property simulations are reviewed. Computational methods, including finite element analysis and machine learning, are highlighted for their roles in alloy design and manufacturing, such as casting and additive manufacturing. Comparisons between model predictions and experimental results demonstrate accuracy and limitations. Applications in optimizing material properties and improving manufacturing processes are discussed. By accelerating alloy development and enabling tailored properties, mathematical modeling emerges as a transformative tool, advancing aluminum alloy research and driving innovation across industries.

When machining steel gear blanks for a long time, problems are observed during their turning and machining. Attempts to improve machinability using various heat treatment methods have not been successful. In this regard, the possibility of the influence of changes in the chemical composition of steel on its machinability was analyzed. The goal was set for the machinability of serial steel 18ChGT to be similar to the machinability of automatic steel, without reducing its mechanical properties. The improvement in machinability by cutting automatic steels is due to the presence of inclusions in its structure, which increase the fragility of the chips. These can be chemical compounds of metals (sulfides, phosphides, selenides, etc.), or inclusions of low-strength metals, for example, lead. The analysis of metallurgical processes for steel production led to the conclusion that the use of sulfides is economically feasible. When processing gears made of steel with a high sulfide content, the average resistance of the WNMG080408 pass plate was 214 pieces on the edge, and when processed from serial steel 18ChGT, the average resistance is 180 pcs on the edge, no changes were recorded for the rest of the properties. Also, when processing 18KChGT steel with a high sulfur content, chip formation was improved, and a reduction in lost working time was observed due to a fourfold reduction in the need to replace reusable containers for chips.

The influence of external factors (heat treatment, high pressure) on the optical properties of the samples was analyzed. It was established that samples of pure PTFE4 after the specified external influence increase their throughput, while the largest increase in throughput is observed for samples that were obtained under high pressure, and for samples that were subjected to heat treatment during synthesis, an increase in throughput is characteristic ability with increasing synthesis temperature. For PTFE-4 composites from 5 wt. % CNT (film thickness h=200 μm) samples become opaque in the wavelength range λ=320-1000 nm and regardless of the method of their production, which indicates the possibility of using such materials as absorbing coatings.

The paper briefly discusses the main features of radial-shear rolling and provides an overview of its effect on the formation of an ultrafine-grained structure in various non-ferrous and ferrous metals and alloys. The conducted review showed that radial-shear rolling is the most promising way to form an ultrafine-grained structure in long bars made of both non-ferrous and ferrous metals and alloys, as well as from various composite materials.

This paper aims to study the reinforcement effects of alumina (23) particles on the mechanical properties of base alloy melt of (6061). The samples of metallic composites with dispersed particles percentage (5%, 10% and 15%) are prepared by casting vortex method, which help the particles entrance in the matrix and distribution of it in homogeneous form. The purpose of this study is to improve the hardness, impact strength, tensile strength, and compressive strength, which are increased with the increment of the added particle’s amount due to the hardness of alumina particles. Based on the results it concluded that the value of the durability increases with the increase in the percentages of the particles by weight between three stages. Also, the addition of aluminum oxide particles increased the tensile resistance and thus improved the mechanical properties of the base material. It was also noted that with the addition of aluminum oxide, the melting point of the metal increased and reached about 980 degrees Celsius.

The work is devoted to experimental studies of the influence of radial shear rolling on the microstructure evolution of the VT-1 titanium alloy and its gradient distribution over the cross section, as well as changes in mechanical properties. In the course of the conducted studies, two different types of microstructure were obtained. At the periphery of the bar near the surface, a relatively equiaxed ultrafine-grained structure with a grain size of 300-600 nm was obtained, while in the axial zone of the bar, an oriented striped texture was obtained. The resulting structure difference of the peripheral and central zones indicates the gradient nature of the structure distribution. This type of distribution is confirmed by the results of the microhardness study over the cross section of a bar rolled to a diameter of 15 mm. The ultimate strength after deformation increased by 58%, while the elongation decreased by 15%.

Additive Manufacturing (AM) Technologies are in constant development since their emergence in the late 80s. However, standardization is still in its infancy, owing to the numerous changing variables in each process. One of the most common are the material extrusion process, in which thermoplastic is extruded, also known as fused filament fabrication (FFF). The popularity of this process is due to the relatively simple method as well as the relatively good mechanical properties of the fabricated parts. There are numerous research studies evaluating mechanical properties because the FFF process allows for the investigation of many variables and the production of many parts with a wide range of characteristics. But how good are those characteristics in reality, and how good do we need them to be? It all depends on the application for which those parts are required.

The properties of an array of carbon nanostructures or a material containing its is differ from the properties of individual components. For bulk array of carbon nanostructures it is unknown to what extent the electrons of each layer participate in conductivity, the role of defects is not defined. properties. So, this work presents some answers to these questions.

The article describes the concept of a new forging method of circular cross-section blanks in a forging tool, the design of which makes it possible to develop significant alternating deformations in the deformable metal. The results of comparative studies of the microstructure and mechanical properties of AISI-5140H low-alloy structural steel, formed in a new forging tool that implements alternating deformation and in flat strikers are presented.

At present, various types of steel grades are used in the production of welded structures and assemblies, resp. combinations of ferrous and non-ferrous metals. In these mutual combinations, it is necessary to know the specifics of weldability of both materials, to choose a suitable welding technology and a suitable filler material. In the experimental part, the quality of heterogeneous welded joints was verified by the GMAW method. A protective gas atmosphere of 82% Ar + 18% CO2 was used for welding (M21 – ISO 14175: 2008). The possibilities of welding and mutual combinations of austenitic stainless steel with structural non-alloy steel, structural alloyed high-strength steel with structural non-alloy steel were assessed. The quality of welds was evaluated using non-destructive and destructive tests in terms of standards: visual test STN EN ISO 17637, capillary penetration test STN EN ISO 22476-12, internal errors were evaluated using radiation tests STN EN ISO 17636-1. The destructive tests used the tensile test STN EN ISO 6892-1, the weld fracture test STN EN ISO 5173 and the Vickers hardness test STN EN ISO 6507-1, the bending impact test STN EN ISO 9016 and the metallographic analysis according to STN EN ISO 17639.

New special high nitrogen steel used in arms industry is developed. The new steel and technology of its production are developed on the basis of the metallurgy under pressure. The mechanical properties by the results of the short -term strength and notchimpact strength tests are determined. The new steel has higher mechanical characteristics in comparison with conventional nitrogen free analogue. Non-destructive control is carried out. Dense structure without defects is established.