Study on the influence of load and sliding speed on the friction behavior of electrodeposited Ni–SiC composite coatings

This study investigates the dry sliding tribological behavior of electrodeposited Ni–SiC composite coatings fabricated using a circulating-solution electrodeposition (CSD) technique on low-carbon steel tubular substrates. By adjusting current density (5–15 A/dm 2 ), coatings with varying SiC contents (6.06, 8.65, and 12.39 vol.%) were prepared and evaluated under different loads (10, 15, and 20 N) and sliding speeds (0.04, 0.08, and 0.12 m/s). The coating containing 8.65 vol.% SiC exhibited optimal performance, achieving the highest hardness (526.5 Hv) and lowest wear rate due to well-dispersed particles and enhanced dispersion strengthening. Increasing sliding speed significantly reduced wear and coefficient of friction (COF), attributed to the formation of a continuous tribo-oxidative layer. In contrast, excessive SiC content or high loads resulted in particle agglomeration and intensified three-body abrasion, degrading both friction stability and wear resistance. A 3 3 factorial statistical design revealed strong nonlinear and interaction effects among the three key parameters. Furthermore, a mechanistic wear map was proposed to illustrate transitions between abrasive and mixed wear regimes under various tribological conditions. These findings offer comprehensive insight into the process–structure–property relationship of Ni–SiC coatings and provide a basis for the performance optimization of protective coatings in high-friction applications.