Development of the functional diagram of influence of the basic factors of the MDO process on the properties of coatings

To protect the parts and assemblies made of aluminum alloy, from corrosion, coatings are obtained by electroplating, which do not always meet the requirements for corrosion resistance. This method has several disadvantages associated with the use of aggressive electrolytes (solutions of strong acids), the presence of additional operations involving surface preparation (preliminary degreasing, etching), as well as the need for the availability of the technological cycle refrigeration. Therefore there is a need for new methods to protect aluminum alloys from corrosion. One of the promising methods of applying protective coatings on aluminum alloys is microarc oxidation (MAO) To form a coating with the desired performance characteristics, the concept relationships MDO process parameters with the properties of the coatings was designed. To confirm the theoretical assumptions research works to identify patterns of influence of technological regimes micro-arc oxidation on the mechanical properties of the coatings were made. The regularities of the influence of technological modes of micro-arc oxidation on the mechanical properties of the coatings was made. It was found that the corrosion rate of MAO coatings in terms of accelerated tests is 0,088 mm / year, which is 5 times lower than the solid anode-oxide coating 0.4175 mm / yr, obtained by electroplating. The obtained data and calculations with respect to the groups of corrosion resistance can be judged on higher corrosion resistance MDO coatings in corrosive environments, as compared with coatings obtained by electroplating.