This article analyzes the effect of electrolytic plasma nitriding on the performance of medium-carbon steel 45 under increased mechanical loads and in aggressive environments. Nitrided samples in carbamide electrolytes, both with and without the addition of ammonium nitrate, were compared to the initial material. SEM with EDX and XRD analysis was used to examine the microstructure and phase composition of nitrided samples. Wear resistance was studied using the ‘ball-on-disk’ method and Vickers microhardness testing, while corrosion resistance was studied using potentiodynamic polarization curves. The study results show that the sample without ammonium nitrate demonstrated better mechanical and corrosion properties due to a more homogeneous and denser nitride layer, approximately 10 µm thick, containing phases FeN and Fe₄N. Its wear resistance doubled compared to that of the initial sample. The sample treated in an electrolyte with the addition of ammonium nitrate demonstrated a higher current density (2.8672 × 10⁻⁵ A/cm²) and a lower corrosion potential (−0.565 V) compared to the initial sample (i_corr = 1.8971 × 10⁻⁵ A/cm², E_corr = −0.480 V) and the sample without ammonium nitrate (i_corr = 1.7315 × 10⁻⁵ A/cm², E_corr = −0.376 V). This is due to the formation of an uneven nitride layer and the presence of microcracks on the surface.

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.

This work is a study aimed at optimizing the process of superarc metallization, with a focus on the effect of stress 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...

This article evaluates the electrolyte-plasma hardening (EPH) of steel 45 using an electrolyte based on sodium carbonate (Na₂CO₃). Theoretical foundations of the electrolysis process of a sodium carbonate aqueous solution were studied during the course of the work. The mechanical and tribological properties of 45 steel samples after EPH were studied. It was found that with an electrolyte composition of 20% Na₂CO₃ and 80% distilled water, a hardened zone with a thickness of up to 5 mm is formed after EPH. The increase in microhardness reached up to 690 HV, which corresponds to a 3–3.5 times increase compared to the initial state. The results of tribological tests showed that the friction coefficient of steel 45 decreased after EPH, indicating a significant improvement in tribological characteristics compared to the initial value before hardening. Electrochemical tests on the corrosion resistance of steel 45 were also carried out. After EPH, the corrosion rate significantly decreased for steel 45 samples, indicating its highest corrosion resistance.

This study examined the effect of electrolytic plasma hardening (EPH) on the properties of 45-grade steel, which can serve as an alternative to traditional heat treatment methods used before the release of finished products. The results of the experiments showed that the mechanical and operational properties of 45-grade steel significantly improved after the application of EPH. Steel 45, widely used in mechanical engineering and agricultural machinery production due to its strength characteristics and durability, demonstrated a significant increase in performance after treatment. It was observed that the properties of 45- grade steel improved considerably after applying electrolytic plasma hardening methods, with the hardness of the samples increasing by 3.1-3.62 times, and wear resistance improving by 7 times. Moreover, the study highlighted the economic efficiency of the proposed treatment method, showing that the introduction of EPH can lead to a significant reduction in material costs, extended product life, and improved environmental performance by reducing energy consumption and emissions. The use of a non-toxic 20% sodium carbonate solution in EPH contributed to the uniform distribution of electric current in the cell and allowed for achieving optimal cooling rates of the sample.

This study investigates the influence of electrolytic cell parameters on the electrolyte boiling rate during electrolytic plasma processing, a critical stage for plasma formation and subsequent surface modification. Focusing on a coaxial cell configuration with a conical anode and cylindrical cathode, this research employs analytical calculations based on the solution of the Laplace equation in spherical coordinates, validated by numerical simulations using the finite element method (Elcut 6.6), to predict electrolyte boiling times. These results are compared with experimental data, demonstrating good agreement, particularly at higher voltages (−200 V). The analysis reveals that while a simplified model provides a reasonable first approximation, it deviates at lower voltages (−50 V) due to the increasing importance of heat removal, neglected in the model construction. This discrepancy underscores the need for more sophisticated models accounting for non-uniform current distribution and heat transfer effects in complex cell geometries. The findings contribute to a deeper understanding of cathodic electrolytic plasma processing (EPP) dynamics and provide a foundation for optimizing cell design and process parameters for industrial applications such as diffusion saturation of steel components.