Assessment of surface texturing of sustainable HVOF sprayed Al2O3+C powder coating

In the current work, sustainable high-velocity oxy-flame-sprayed Al2O3+C powder coatings with and without annealing heat treatment were investigated for residual stress, sliding wear rate, and corrosion behavior. The field emission scanning electron microscopy + energy-dispersive X-ray spectroscopy result displays typical lamellae-forming, unmelted grains that bend plastically when struck at high velocities. The micro-hardness values of the as-deposited and annealed samples increased to roughly 21.8% after the wear test due to work hardening and microstructural changes brought about by annealing, while the annealed sample’s overall measured micro-hardness values increased to roughly 41.8% when compared to the as-deposited sample. The wear rate values of the as-deposited and annealed samples decreased to ≈88% and 96%, respectively, after the wear test. In comparison to the as-deposited samples after the wear test, the mass loss of the annealed samples decreased to 62.8%, as per the experimental results. The study systematically analyzes the effect of annealing at different temperatures, revealing significant enhancements in mechanical properties due to work hardening and microstructural changes. The results demonstrate notable reductions in wear rates (up to 96%) and mass loss (by 62.8%) for annealed samples compared to as-deposited ones, highlighting the annealing process’s efficiency in improving the durability and performance of the coatings.