Methods of Distributing the IF-WS2 Modifier for Its Introduction into the Structure of the Al2O3 Aluminum Oxide Coating

Abstract

The microstructures and structures of modified Al2O3/IF-WS2 coatings prepared on aluminum substrates are studied. Amorphous Al2O3 oxide coatings are obtained on EN AW 5251 aluminum alloy using the electrooxidation process. The quality of the IF-WS2 nanopowder is of great importance in the process of its introduction into the nanopores of the Al2O3 oxide coating. Commercial nanopowder tends to agglomerate, and without appropriate pretreatment, it is difficult to introduce it into the nanopores of the coating. To improve the degree of fragmentation of the IF-WS2 nanopowder, an experiment was carried out to distribute the nanopowder in the presence of strong ultrasounds, and new conditions for introducing the powder into the nanopores were used. A two-level design of experiment (DOE) was used. The SEM examination made it possible to conclude that Method A contributed to a more even distribution of nanoparticles in the microstructure of Al2O3 coatings. GIXD analyses showed the presence of WO3 derived from the IF-WS2 modifier next to crystal structures derived from aluminum and WS2. Modification of coatings using Method A resulted in surfaces with lower contact angles measured with polar liquids and higher surface free energy compared to Method B.