Influence of Microstructure and Mechanical Properties on the Tribological Behavior of Flame Sprayed Al₂O₃-TiO₂ and WC-NiFeCr Coatings

In this work, the influence of microstructure, hardness, elastic modulus, and fracture toughness on the tribological behavior of flame-sprayed Al₂O₃-TiO₂ and WC-NiFeCr coatings is investigated. Fracture toughness was found to be the most influential property, with higher toughness corresponding to greater wear resistance. This relationship, however, is verified only up to the point where the applied stresses cause detachment of particles from the surface. Hardness emerged as a less dominant factor than fracture toughness, elastic modulus, and porosity due to the fact that ceramic coatings, despite their high hardness, have low relative wear resistance.