Sliding wear performance of high-velocity oxy-fuel spray Al2O3/TiO2 and Cr2O3 coatings:

High-velocity oxy-fuel (HVOF) spray ceramic oxide coatings have immense potential in industrial applications. However, they are not widely used yet due to the lack of an adequate scientific database created after testing these coatings for specific industrial applications. Two such ceramic coating powders, Al2O3+(40%)TiO2 and Cr2O3, were deposited on AISI 309 SS stainless steel by the HVOF spray technique, in order to enhance its wear resistance. This stainless steel is used in many components of thermal power plants in India, where it suffers one or more types of wear. The as-sprayed coatings were characterized by XRD and SEM analyses. Subsequently, the sliding wear behaviours of the uncoated, HVOF spray Al2O3+(40%)TiO2 and Cr2O3 coated AISI 309 SS were investigated according to ASTM standard G99-03 on a pin-on-disc wear test rig. Cumulative wear rate and coefficient of friction (μ) were calculated for the coated as well as the uncoated specimens for 30, 50, and 70 N normal loads at a constant sliding ve...