As high-end equipment manufacturing advances, demand for improved surface performance in critical components has increased. Laser cladding is an advanced surface strengthening technique that affords effective surface modification. During the laser cladding process, obtaining a fine grain microstructure usually helps to enhance the microhardness, wear resistance, and corrosion resistance of the cladding layer. However, conventional laser cladding often yields coarse columnar grains that limit further performance improvements, so process optimization to achieve grain refinement is necessary. In this study, oscillating laser cladding was combined with a pulsed-wave (PW) laser mode to deposit a fine-grained Al₂CrFe₂Ni₄Ti_1.5 high-entropy alloy cladding on Q550 steel substrates. Compared with continuous-wave (CW) laser cladding, the PW mode produced markedly refined grains and concomitant improvements in microhardness, wear resistance, and corrosion resistance. Specifically, the microhardness of the PW cladding layer reached approximately 673.34 HV_0.5, the wear volume was approximately 0.06 mm³, the wear rate was approximately 0.21 × 10⁻⁴ mm³/N·m, and the corrosion current density decreased to approximately 1.212 × 10⁻⁵ A·cm⁻². This work presents a novel approach for producing high-performance, wear-resistant, and corrosion-resistant high-entropy alloy cladding layers, and offers both theoretical insight and potential engineering applications.

The challenging wind conditions surrounding power transmission lines exacerbate the wear and corrosion of transmission line fittings. Thermal diffusion galvanizing technology, a novel method for obtaining galvanizing layers, significantly enhances the wear and corrosion resistance of metal components, thereby extending their service life. Holding temperature plays a critical role in determining the performance of the thermally diffused zinc coating. In this study, we prepared thermally diffused zinc coatings containing rare earth oxides on 35CrMo steel at various holding temperatures and evaluated their morphology, wear resistance, and corrosion resistance. The findings indicate that increasing the holding temperature enhances the diffusion of zinc and iron, yielding thicker coatings with a maximum thickness of 60 μm at a holding temperature of 450 °C. Notably, the zinc coating produced at a holding temperature of 410 °C exhibits optimal wear resistance at room temperature, and the wear failure mechanisms were predominantly abrasive wear and oxidative wear with slight adhesive wear. In addition, the zinc coating produced at a holding temperature of 430 °C exhibits optimal corrosion resistance at room temperature.

This study investigates the influence of modification on the microstructure and properties of Mn–Si–Cr alloy steel. The results indicate that the as-cast microstructure of Mn–Si–Cr alloy steel is composed of black acicular bainitic ferrite lath and white retained austenite. The microstructure of the alloy steel changes to martensite, austenite, and carbide after quenching and partitioning treatment. After rare-earth magnesium modification and compound modification, the as-cast microstructure of Mn–Si–Cr steel becomes more refined and displays a more regular arrangement. Furthermore, the martensite and austenite grains in the modified samples show refinement, and the arrangement of martensite is more systematic. Additionally, the amount of austenite decreases, and the amount of carbides increases after quenching and partitioning heat treatment. In comparison with the unmodified samples, the modified samples show negligible changes in hardness. However, the impact toughness of modified quenched and partitioned steel increases by 20 %. Moreover, the wear resistance of compound modified quenched and partitioned steel is 38 % higher than that of the unmodified sample. The compound modified sample steel exhibits excellent wear resistance and comprehensive mechanical properties.

In this work, the microstructural evolution and comprehensive performances (mechanical, wear, and corrosion resistance) of LDED-fabricated 2205 DSS subjected to heat treatment at 1000 °C for different holding durations (5 min, 10 min, 30 min, and 60 min) were systematically investigated. The results indicate that the austenite content gradually increases with the extension of heat treatment time, reaching a peak value of 51% at 30 min. Meanwhile, the austenite morphology transforms from dendritic grains to equiaxed grains, accompanied by the massive precipitation of intragranular austenite (IGA) and obvious elemental enrichment behavior. In terms of mechanical and functional performances, the microhardness decreases slightly with prolonged heat treatment, with a total reduction of only 7%. The elongation increases continuously, while the yield strength and tensile strength remain relatively stable. Additionally, the wear coefficient and wear rate present a trend of first decreasing and then increasing. The minimum wear rate of 48.32 × 10⁻⁶ mm³/(N·m) is obtained at the heat treatment duration of 30 min, which is 83.4% lower than that of the untreated sample. Moreover, the optimal corrosion resistance is achieved after 30 min of heat treatment, with the corrosion current density decreasing by 45.8% relative to the as-built specimen. These results demonstrate that heat treatment at 1000 °C for 30 min is an optimal processing parameter to significantly optimize the microstructure and comprehensive performances of LDED-2205 DSS.