Structure and Properties of Composite Coatings with Zro2 and Tio2 Particles After Lehceb Treatment

Abstract

The paper presents the comprehensive analysis of the structure, properties, and corrosion of micro-arc coatings with ZrO₂ and TiO₂ particles after the low-energy high-current electron beam (LEHCEB) treatment. The coating morphology, microstructure, phase and elemental compositions are investigated by the scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray powder diffraction. After the LEHCEB treatment, the coating structure with ZrO₂ particles changes from friable and porous to denser with closed spheroidal pores. It is shown that the adhesive strength of the coating with ZrO₂ particles increases with the critical load growth from 10 to 18 N. Moreover, the treatment enhances its corrosion resistance, as evidenced by a reduction in the corrosion current from 7.48∙10^–7 to 1.05∙10^–8 A/cm² and an increase in polarization resistance from 0.9·10⁴ to 5.77∙10⁶ Ω·cm². In contrast, the coatings with TiO₂ particles exhibit a more porous structure due to the volatilization of low-melting components (sodium silicates), as evidenced by a reduction in the concentration of Na and Si elements in their composition. The adhesive strength and corrosion resistance of the coatings with TiO₂ particles deteriorate after the treatment.