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

Laser processing is often used in many technological processes for welding, cutting, marking, etc. However, it has been gaining popularity for several years as a surface modification process, including cleaning, polishing, surfacing, and hardening. These methods are used to modify the physicochemical properties to enhance hardness, wear resistance, corrosion resistance, and the propagation of microcracks on the metal surface. It has been found that the effectiveness of laser radiation (short pulses of laser light) depends on the thermal properties of the alloy being treated and the process parameters. Also significant is optical absorption, which determines the coupling of laser radiation energy to the workpiece during the melting of its surface. The study, considered preliminary, was conducted on flat sparrows of AlSi11 alloy under argon shielding. It was possible to fragment the microstructure components of the studied alloy at depths of several micrometers, depending on the laser power density, spot size, and travel speed. The fragmented α(Al) dendrites in the melted laser zone are oriented toward the temperature gradient. At the very surface, they gradually lose their secondary arms, assuming the morphology of compact cells. This method can harden large or local areas that are inaccessible to other surface treatment methods, such as piston ring gaps in internal combustion engines, specifically the part of the piston shell that operates under extreme thermo-mechanical and tribological stresses.

Are investigated mechanisms and kinetics of structural transformations polymeric substrates and of disperse particles fillers and modifiers exposed defocused laser radiation with energy in the range of 1.5 to 6 J. Installed effect of hardening the thermoplastic matrices (polyolefins, polyamides, of polyesters) when exposed to short laser pulses on a film sample thicknesses of 50-200 microns. The methods of structural analysis (IR spectroscopy, X-ray diffraction, DTA) showed, that the predominant mechanism of manifestation hardening effect is the formation of nano-sized structures in the film sample volume due to leakage of recrystallization processes. When exposed to laser radiation to disperse and fibrous particles of silicates, graphite, schungite, carbon fibers is implementing a complex effect of increasing the dispersion and the formation of advanced morphology of the surface layer with an increase in the proportion of nano-sized fragments whisker and lamellar habitus. When laser irradiation of fibers fragments formed developed morphology of the surface layer, due to the occurrence of thermal degradation processes that lead to the appearance of cracks and of globular indentations. Spectroscopy method of thermally stimulated currents (TSC – spectroscopy) established the effect of changing the energy state of the surface layers of substrates and particulate modifiers, which are characterized by extreme values of magnitude TSC – currents in the temperature range 193-523 K. The combined effect of energy and morphological factors provides the effect of increasing the activity of modifying components subjected to the laser processing. Changing the energy state of the surface layer of the polymer substrate has a beneficial bactericidal effect, increases the effectiveness of antiseptic treatment of medical devices used in medical practice. Are presented examples of the practical use of the established laws when creating polymer composites for metal-polymer systems for various applications.

Viewed the theoretical questions regarding the kinematic and structural parameters of the working tool when rolling out the cylinder liner.