The development of aviation and the improvement of the flight characteristics of aircraft and helicopters requires the use of CFRP carbon fibers and GFRP fiberglass in power structures. The vibration load factor is an integral part of the aircraft design. With vibrations, a contact that we thought was nominally stationary begins to move at the micro level over time. Movement between parts is sufficient for the catastrophic development of fretting-corrosion wear of contacting parts, followed by the development of fatigue cracks and structural failure. Therefore, it is very important to pay attention to increasing the durability of contact made of Ti-GFRP/CFRP materials under vibration loads, since as a rule, these are power parts of aircraft, damage to which significantly reduces the reliability of the structure and increases the risk of fatigue cracks, especially in parts made of titanium alloys. One method of increasing the durability of the Ti-GFRP/CFRP contact is the use of intermediate "sacrificial" materials that are triggered during operation and replaced during repairs, but protect the contact from damage. The paper analyzes wear-resistant composite materials and determines what materials F4К15М5 and ZX550 are most suitable for this. It was found that during tests in the Ti-F4К15М5-GFRP system, the metal surface is completely protected by spreading an intermediate material on the surface. The mechanisms of wear of intermediate materials and their effect on contact under vibration loads have been determined.
The results of studies of friction and wear of detonation composite nanocoating’s based on the ternary compound aluminum-magnesium-boron under test conditions with constant load in the sliding velocity field are presented. Their structural-phase composition and passivating complex of surface oxide structures are determined using modern physical analysis methods. It is established that the parameters of wear intensity and friction coefficients are minimized due to the set of surface structures that regenerate a stable self-lubricating structured layer under friction conditions. Factors that influence the formation of dynamic equilibrium of a self-lubricating layer that has an effective ability to self-repair are determined. At the same time, a continuous protective layer screens the processes of molecular-adhesive interaction and blocks the development of unacceptable destruction phenomena.
The study develops an integrated approach for selecting wear-resistant materials for technological devices used in machining and repair of internal combustion engines, considering mechanical, thermal, economic, and reliability factors. KHVG and R6M5 steels were comparatively analyzed using modified abrasive wear models, Weibull reliability assessment, and Life Cycle Cost (LCC) analysis. The model accounts for temperature-induced hardness degradation, lubrication conditions, contact geometry, and coating adhesion. It was established that at temperatures above 400 °C and severe abrasive wear, R6M5 steel provides longer service life and reduces LCC by 6–19% compared to KHVG steel. Under moderate temperatures and impact loading, KHVG steel is preferable due to higher fracture toughness. Optimal heat treatment regimes were determined for both steels. Lubrication increases service life by approximately 66%, while risk mitigation measures are more effective than material substitution under high failure probability conditions. TiN coating is not recommended for rough surfaces because of delamination risk. The developed model enables improved engineering decision-making for wear-resistant tooling applications.
A solution to the problem of protecting niobium from high-temperature, highly intensive oxidation is considered. The isothermal and thermocyclic creep and long-term strength characteristics of a niobium alloy with three coating variants are determined at temperatures of 1400–250°C in air. A test methodology for niobium alloys with coatings under simultaneous loads, high temperatures, abrupt thermal cycles, and an oxidizing environment with radiant heating and non-contact cooling by focusing radiant energy is presented, ensuring reliable determination of mechanical properties. A comparison of ultimate strains, creep rates, and durability under isothermal and thermocyclic conditions for the three coating variants is conducted, demonstrating the advantage of a combined plasma-diffusion coating over silicide and borosilicide coatings. Differences in creep and long-term strength characteristics of the three coating variants are demonstrated, which are explained by the nature of crack development in the coating. The transition from single “sharp” cracks in the coating to regular cracks in the diffusion sublayer with rounded tops ensures an increase in the strength and durability of the niobium alloy.
The article presents a scientifically based, improved methodology for the design calculation of the parameters of a garbage truck’s sealing plate mechanism, developed through an analysis of scientific literature and taking into account the wear of its hydraulic cylinder, in order to determine the main geometric, force, and speed characteristics. The drive for the working components of the sealing plate mechanism is hydraulic and is powered by the garbage truck’s pump station. The application of the proposed improved engineering calculation methodology allows for a significant reduction in design time and avoids unnecessary costs associated with conducting complex experimental and theoretical studies. Using the developed methodology, the main geometric, force, and speed parameters of the garbage truck’s sealing plate mechanism were determined, taking into account the wear of the hydraulic cylinder. It has been established that further refinement of the engineering calculation methodology for the garbage truck’s sealing plate mechanism using a load-sensitive scheme requires additional research
