Improving Abrasion Resistance of Low Temperature Enamel (LTE) Coating by Alumina Addition

Low temperature enamel (LTE) coating has advantages in material durability, hardness, corrosion resistance, and high-temperature tolerance, but shows unsatisfying abrasion resistance due to its brittle nature. Here, alumina was added to the LTE coating with contents of 0, 5, and 10 wt%. The thermal stability of alumina in the LTE matrix and the microstructure, phase composition, microhardness, impact resistance, adhesion strength, abrasion resistance, and corrosion protection properties of different LTE coatings were investigated. Results indicated that alumina had high thermal and chemical stabilities in the LTE matrix without affecting the pore structure of the coating. As an abrasion-resistant filler, alumina increased the hardness and impact resistance of LTE coatings while reducing adhesion strength. In the abrasion test, alumina showed an advantage in delaying the formation and expansion of cracks, and the alumina-enhanced LTE coating demonstrated a 70 % reduction in mass and thickness losses when compared to pure LTE coating. In particular, all LTE coatings survived 8000 cycles of abrasion without significant degradation in corrosion protection. The findings of this study confirmed the feasibility of alumina as an abrasion-resistant filler and provided a modified LTE coating for coupled corrosion and abrasion conditions.