ELECTRIC MODES OF MICROARC OXIDATION: INFLUENCE ON PROCESS AND COATING PROPERTIES

The article discusses the effect of microarc oxidation (MDO) modes on the structural and phase state, mechanical, physical and functional characteristics of oxide coatings. Microarc oxidation (MDO) is a promising method for modifying the surface of metals, allowing the formation of durable oxide coatings with improved performance characteristics. This article examines the effect of the MDO modes, namely direct (direct) and alternating (pulsating or bipolar) currents, on the morphology, structural and phase state, mechanical and tribological properties of oxide layers. A comparative analysis of the characteristics of coatings obtained under various processing modes has been carried out, and their advantages and disadvantages have been identified. Experimental data show that the use of alternating current contributes to the formation of dense, homogeneous, wear-resistant coatings with low porosity and high adhesion to the substrate. At the same time, coatings obtained using direct current have a pronounced porous structure, which improves their anti-corrosion properties. The results obtained make it possible to better understand the mechanisms of formation of oxide layers and optimize the modes of microarc oxidation to obtain coatings with specified properties. The presented data can be useful for the development of new materials with improved functional characteristics in various industries. Keywords: microarc oxidation, direct current, alternating current, pulse mode, bipolar mode, oxide coatings, structural-phase state, microhardness.