The Influence of Methods for Distributing the IF-WS2 Modifier into the Structure of Al2O3 Aluminium Oxide Coatings on Their Micromechanical Properties

This work examines the micromechanical response of Al2O3/IF-WS2 (IF-inorganic fullerene-like) composite coatings formed on the EN AW 5251 aluminium alloy by anodic oxidation. The resulting amorphous oxide layer contains a nanopores system that can be filled with IF-WS2 particles, provided the modifier is properly dispersed. Because commercial IF-WS2 powders exhibit strong agglomeration, a high-intensity ultrasonic treatment was applied to enhance particle separation before incorporation. The influence of newly established incorporation parameters was assessed using a two-level experimental design. As part of the research, analyses of the microstructure, micromechanical, and sclerometric properties were performed. Cross-sectional SEM observations confirmed the presence of IF-WS2 within the oxide structure and revealed differences in particle distribution, depending on the incorporation technique used. The results indicate that although microhardness and Young’s modulus are largely insensitive to the nanopowder incorporation method, the interaction between the anodising current density and the incorporation technique significantly influences the strain energy components and tribological response of the coatings. These findings suggest that appropriately selected processing parameters can be used to tailor the mechanical and tribological properties of Al2O3/IF-WS2 coatings to specific loading conditions and functional requirements, rather than striving for a single, universal, optimal processing configuration.