Hybrid polytetrafluoroethylene oxide coatings on aluminum and titanium formed by plasma-electrolytic oxidation

Abstract

Regularities of the formation of plasma-electrolytic oxide coatings on aluminum and titanium from an aqueous Na2SiO3 + NaOH electrolyte solution containing silicate-acrylate emulsion and dispersed polytetrafluoroethylene particles are studied. Coatings, the surface part of which is composed chiefly of polytetrafluoroethylene and destruction products of polytetrafluoroethylene and emulsion, are produced. The water contact angles of the coatings may be as large as 105°. The presence of polytetrafluoroethylene in the coatings increases the time of their mechanical abrasion by several exponents. The dependence of the composition and thickness of coatings and the microstructure of the coating surfaces on the content of polytetrafluoroethylene in the electrolyte is considered.