Dry Sliding Wear Behaviours of Intrinsically Sintered Micro-Arc Oxidation Coatings on Pure Aluminum
Wear behaviours of micro-arc oxidation (MAO) coatings on pure aluminum in a phosphate based electrolyte were investigated. The surface morphology, cross-section morphology and elements distribution of coatings were observed by scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). Wear test was proceeded with improved pin-on-disk tester under the dry sliding friction condition at load of 10 N. The results show that coatings structure are poly-porous and uniform, the components in the phosphate electrolyte do not participate in the formation of coatings, coatings are oxidized and sintered intrinsically. Wear weight loss of MAO coatings decrease by a factor of 20 in compare with the pure aluminum substrate, and abrasive wear assisted stripping from micro-cracking is predominant wear mechanism.