Mechanism, models, and influence of heterogeneous factors of the microarc oxidation process: A comprehensive review

Abstract The shortcomings of the microarc oxidation (MAO) technology are revealed, in accordance with which a range of topical scientific problems that need to be solved is formulated. It is shown that, despite significant progress in this area of research, there are still controversial issues related mainly to the features of the emergence and combustion of microdischarges. In order to develop a scientifically substantiated approach to the choice of the optimal mode for deposition of microarc oxide coatings, regularities in the influence of heterogeneous factors on their properties are systematized. The analysis of scientific works devoted to the mathematical description of the MAO process has been carried out. It is shown that the existing mathematical models have limitations, and are applicable only to certain aspects of coating formation and do not describe the MAO process as a whole. The prerequisites, recommendations, and theoretical provisions that can be used in the development of a complex mathematical model of the MAO process are revealed. Known methods of analytical description of the forming curve are considered. The possibility of using the forming curve for determining the correct choice of technological parameters and predicting the oxide coating properties during their formation is shown.