Nº 5 (167) (2025)
Additive technologies and laser processing
TECHNOLOGY FACTORS EFFECT ON THE QUALITY PARAMETERS OF PRODUCTS MANUFACTURED BY THE WAAM-TECHNIQUE BASED ON GMAW (GAS-METAL-ARC-WELDING)
Resumo
The object of research in the article is a welding procedure of additive manufacturing based on automatic wire electrode arc welding in a shielding gas environment– DED-W / WAAM-GMAW. The article presents the classification of DED technologies and their comparative characteristics. The advantages of WAAM processes based on GMAW are illustrated. The controlling factors of WAAM-GMA technologies that influence quality parameters of manufactured products and the output parameters of the process are specified for the evaluation of engineering capabilities in WAAM-GMAW. The mechanisms of metal transfer during its deposition onto the formed blank part are viewed. Comparative characteristics of transfer modes are presented, and their effect on the course of GMAW processes is evaluated. The influence of such factors as the polarity of the electrode wire connection, the current strength and voltage of the welding arc power source, the wire feed rate, the speed of movement of the welding blowpipe (welding bath), shielding gas composition on the product quality parameters and WOL is viewed. The aspects of path modeling of the shaping movements of the welding blowpipe in the WAAM-GMAW procedure affecting the thermal processes of WOL, the geometric accuracy and shape of the blank part, and the mechanical properties of the work material are described. The disadvantages of the method related to the possible defects in products, such as high surface roughness and undulation, anisotropy of the mechanical properties of the material, metal overflows on the side surface of the blank, residual stresses, porosity, cracks and delamination, are focused on. The causes of defects are listed. An analysis of the proneness of various materials to various defects is presented. Information is provided on the degree of influence of some of the controlling technology factors of the WAAM-GMAW procedure on the WOL parameters and the generated product quality parameters. A number of solutions have been proposed to improve the reliability of forming the quality parameters for products obtained by WAAM-GMAW methods.
Science intensive technologies in mechanical engineering. 2025;(5 (167)):3-14
3-14
DEVELOPMENT OF PULSED LASER DEPOSITION PROCESS IN NANODIMENTIONAL STRUCTURES
Resumo
Promising directions of PLD method application are presented: high-temperature superconductivity, carbon nanostructures, thermoelectric structures and topological insulators based on bismuth telluride. Vacuum physical deposition of thin films (PVD) technologies, such as pulsed laser deposition (PLD), play an important part in microelectronics and other industries. PLD has been actively developed since the 1960s, becoming a powerful tool for creating nanoscale films and high-temperature superconductors. One of the most important achievements of PLD was the production of a high-quality film of the high-temperature superconductor YBa2Cu3O7, opening up new opportunities in the field of superconductors. The PLD method has a unique combination of properties that provide high versatility and broad research potentialities. The key feature of the PLD method is the powerful (more than 1 MW/cm2) impact on the target with short (less than 30 ns) pulses. The method is based on evaporation of a target by a laser beam and deposition of the material on a substrate in a vacuum environment. A special feature of PLD is the high accuracy of control of the composition and structure of deposited materials, which makes it unique among other PVD methods. PLD is also widely used to produce carbon nanostructures, including graphene and diamond-like coatings (DLCs), which find applications in various fields, from supercapacitors to medical implants. In addition, the PLD method has been successfully applied to the formation of thin-film thermoelectric materials based on bismuth telluride, which are used in sensors and temperature stabilization systems. Wide versatility and efficiency of PLD make it a key tool in modern research and development of new materials in microelectronics, quantum technologies and energy.
Science intensive technologies in mechanical engineering. 2025;(5 (167)):15-21
15-21
CHARACTERIZATION OF ACCOMPANYING RADIATION UNDER LASER PROCESSING OF STAINLESS STEEL 12CR18NI10TI
Resumo
Research results of accompanying radiation produced by laser processing of material handling are presented, and energy characteristics in various wavelength ranges are determined. This issue is relevant both in the technological sphere and in the fields of medicine and labor protection. The theoretical and experimental determination of the accompanying radiation spectra will make it possible to assess the presence of specific wavelengths that can destabilize laser processing, in particular, stainless steel 12Cr18Ni10Ti, as one of the most in demand in industrial applications. The dependence of accompanying radiation spectrum on the chemical composition of the handled material was assessed using specialized software. By theory, it was found that the emission spectra of 12Cr18Ni10Ti stainless steel are in the UV, violet and green wavelength ranges. In the experimental work, an automated monochromator spectrograph model M266 (Solar laser systems) was used to determine the spectral composition of the accompanying radiation. The obtained spectral analysis results confirm the theoretical data and give supplement information, which is due to the presence of intense thermal effects that software does not take into account. The research results indicate the presence of accompanying radiation in the processing of 12Cr18Ni10Ti stainless steel using the technology of laser marking of spectral lines in the UV wavelength range. A comparison of the values obtained in the theoretical and experimental parts of the study showed the need to combine these two methods of studying accompanying radiation, since it is the combination of theoretical and experimental data that allows levelling disadvantages of each method and obtain the most complete spectral picture of accompanying radiation. The recorded research results, in particular the presence of UV spectral lines, necessitate measurements of the energy characteristics of accompanying radiation in the UV range, not only when laser marking, but also under various laser processing, determining specific levels in order for potential hazard rating to personnel.
Science intensive technologies in mechanical engineering. 2025;(5 (167)):22-29
22-29
Technologies of mechanical processing of workpieces
PROCCESSING CHARACTERISTICS STUDY FOR THE ALLOY OBTAINED THROUGH ADDITIVE TECHNOLOGY EBAM (INCONEL 625) UNDER MILLING
Resumo
The features of milling of the difficult-to-process heat-resistant inconel 625 (analog of CrNi75MoNbTiAl) are viewed. The sample was obtained using the EBAM additive technology using an electron beam installation. By means high-precision analytical equipment, microstructure and physico-mechanical properties were studied on samples cut far and wide of feed path under synthesis. Acting cutting forces were measured under milling in various modes using a Kistler dynamometric turning appliance. The schemes for measuring cutting forces and their direction, depending on the contact conditions of the milling cutter and stock material were explained. Carbide end mills uncoated with diameters of 8 and 12 mm were used for milling. When measuring the cutting forces components, it was found that an increase in feed in the range of 25...200 mm/min during milling leads to a linear increase in cutting forces. At the same time, there is a stable tendency to exceed cutting forces when milling along the feed direction under synthesis in comparison with similar conditions. In the case of milling against the feed direction under sample synthesis, it was found that the specific cutting force in the limiting modes reaches values of 428 N/mm2. The analysis of the research results made it possible to develop technological recommendations on the assignment of cutting tool parameters and fixing limiting milling modes.
Science intensive technologies in mechanical engineering. 2025;(5 (167)):30-41
30-41
SURFACE WEAR RESISTANCE INCREASE FOR PARTS IN PRECISION FRICTION PAIRS OF AGRICULTURAL MACHINES UNDER FINAL ANTIFRICTION NONABRASIVE MACHINING
Resumo
The results of a study aimed at creating protective adhesive thin-film coatings made of aluminum, which are applied to grade 45 steel using the friction method, are presented. For this purpose, a bar tool is used, fixed in a special device and being subjected to pressure. 45 steel according to GOST 1050-2013, previously degreased with benzene (GOST R 58415-2019, C6H6) or alcohol (GOST R 55878-2013, C2H5OH), was used as samples for comparative tests. After that, the oxide layer was removed from the surface of the samples using an abrasive material (GOST 6456-82), and a layer of glycerin (GOST 6824-96, CH2(OH)-CH(OH)-CH2OH) was immediately applied to preserve the juvenile surface, then followed by coating with a copper-aluminum film. The interaction of films deposited on the surface of samples by the final antifriction nonabrasive machining (FANaM) is studied. The protective properties of aluminum as a coating are investigated. The protective properties of aluminum as a coating are investigated. During the experiments, the conditions necessary for the formation of a solid aluminum layer were determined, and a change in the mass of steel samples before and after coating was recorded. The resulting composite coating proves increased wear resistance, anti-corrosion properties and reduced friction coefficient.
Science intensive technologies in mechanical engineering. 2025;(5 (167)):42-48
42-48