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This study investigated the effects of electron beam irradiation on the mechanical and tribological properties of polyetheretherketone (PEEK), with particular focus on modifications resulting from the application of the Litol-24 lubricant. Samples of pre-treated PEEK were irradiated at doses of 100, 200, 400, and 600 kGy using the ILU-10 linear accelerator. Comprehensive analyses were conducted, including thermogravimetric analysis (TGA) to assess thermal stability, X-ray diffraction (XRD) to observe structural changes, and the impact of irradiation on microhardness. Tribological performance was evaluated using the ball-on-disc method. Results indicate that irradiation decreases microhardness by approximately 19% and modifies the tribological behavior in a dose-dependent manner. TGA results showed subtle shifts in decomposition onset temperatures, with a reduction of about 10 °C post-irradiation, while XRD revealed a 12% decrease in crystallinity, affecting mechanical properties. Further investigations demonstrated that lubrication, particularly under high-load conditions, could enhance the operational characteristics of PEEK post-irradiation. The study underscores the critical role of lubricants in improving the wear resistance and durability of PEEK, making it suitable for high-stress applications in mechanical engineering and manufacturing sectors. The analysis highlighted the potential of integrating electron irradiation into existing material processing workflows to improve the properties of PEEK, thereby extending its utility across various industrial applications. This approach offers a promising avenue for optimizing the performance and longevity of PEEK components, particularly in the environments subject to extreme mechanical stresses. [ABSTRACT FROM AUTHOR]

The continuous development of biomedical materials necessitates exploring new solutions to enhance implant performance. This study investigates the impact of titanium dioxide nanoparticles on calcium phosphate coatings applied to VT1-0 titanium substrates using micro-arc oxidation. Titanium, widely recognized for its excellent mechanical properties and compatibility, serves as an ideal substrate for implants. The coatings were synthesized in an electrolyte with varying titanium dioxide concentrations to examine their influence on surface morphology, wettability, roughness, hardness, and tribological characteristics. Characterization techniques, such as scanning electron microscopy, X-ray diffraction, and profilometry, were employed to analyze the coatings' structural and mechanical properties. The results demonstrate that increasing titanium dioxide concentrations leads to enhanced uniformity, reduced pore sizes, and higher hardness. Furthermore, the coatings showed improved wear resistance and reductions in friction coefficients at optimal nanoparticle levels. The inclusion of titanium dioxide significantly enhances the mechanical and tribological performance of the calcium phosphate coatings, making them suitable for biomedical applications, especially in implants requiring long-term durability and enhanced compatibility. [ABSTRACT FROM AUTHOR]

This work is a study aimed at optimizing the process of superarc metallization, with a focus on the effect of voltage on the properties of the spraying coatings. In this work, 30HGSA grade steel wire was used for the coating of 45 steel, widely used in mechanical engineering. The use of supersonic arc metallizer SX-600 allowed to obtain coatings at different voltages (32 V, 38 V and 44 V) and the same current strength. Various metallization process parameters such as material feed rate, voltage, current, distance and nozzle geometry are discussed in this paper. Using various analytical techniques including X-ray diffraction analysis, microscopy, microhardness and corrosion resistance tests, the qualities of the coatings were evaluated. Particular attention was paid to analyzing the phase composition of the coatings, porosity, substrate bond strength and tribological characteristics. It was found that the voltage during the supersonic arc metallization process has a significant effect on these characteristics. The selected optimum voltage allows to obtain dense and homogeneous coatings with improved performance properties. The results of the study revealed that the best physical and mechanical properties were exhibited by the sample processed at 38 V, which showed lower porosity and improved strength characteristics compared to the other samples. These findings can be used to improve manufacturing processes in industries such as automotive and mechanical engineering, where restoration and improved performance of worn parts is required. [ABSTRACT FROM AUTHOR]

This article presents the results of research on the effects of electrolyte plasma hardening on the structure, phase composition, tribological, and mechanical properties of medium-carbon structural steel 45, which is widely used in the manufacturing of tools and machine parts. Hardening experiments were conducted using an electrolyte plasma hardening setup with electrolytes varying in sodium carbonate (Na2CO3) concentration in distilled water (15%, 20%, and 25%). With a consistent heating duration of 4 s during quenching, significant phase changes in the steel's microstructure were observed, enhancing hardness and wear resistance. The transformation of the initial structure of steel 45, which consists of ferrite and pearlite into martensite on the surface of the samples, led to an increase in microhardness up to 506–690 HV01. This value is 2.5–3.5 times higher compared to the untreated sample, and the thickness of the hardened layer reached up to 3.2 mm. Additionally, wear volume measurements showed that after electrolyte plasma hardening, the wear resistance of the samples increased by 1.3–1.5 times (2.01 × 10−4, 2.26 × 10−4 m3). The obtained results on the changes in microstructure and mechano-tribological properties of steel 45 confirm the potential of electrolyte plasma hardening technology for improving operational characteristics and extending the service life of heavily loaded and critical machine parts. [ABSTRACT FROM AUTHOR]

This article is dedicated to investigating the impact of different electrolyte compositions on the development of titanium coatings endowed with superior mechanical, tribological, and corrosion properties. An experimental analysis was conducted on three distinct electrolyte formulations, each contributing unique attributes to the coating's structural formation. Advanced analytical techniques, including scanning electron microscopy, hardness testing, wear resistance evaluation, and corrosion trials in harsh environments, were employed to gauge the mechanical, tribological, and anti-corrosive performance of the coatings. The utilization of scanning electron microscopy, X-ray structural analysis, and additional methodologies enabled an in-depth characterization of the microstructure and elucidated the relationship between the physico-mechanical properties and the electrolyte's chemical makeup. Among the electrolytes examined, the composition containing potassium hydroxide emerged as superior, fostering coatings with a distinctively porous structure that augment mechanical attributes. A considerable degree of porosity coupled with relatively small pore dimensions suggests the potential to engineer structures that exhibit optimal mechanical robustness. Furthermore, research findings related to this specific electrolyte composition revealed enhancements in the friction coefficient and wear resistance, indicating its promising prospects for tribological applications. The study also meticulously addressed the corrosion aspects, revealing that the microarc oxidation-derived coatings substantially improve corrosion resistance by offering more favorable potentials and currents than the bare titanium substrate. The efficacy of microarc oxidation as an avant-garde technique to advance the properties of titanium alloys underscores its prospective utility and practical relevance in contemporary industrial applications. [ABSTRACT FROM AUTHOR]