DETERMINING FRICTION RATIO OF PLASMA ELECTROLYTIC OXIDATION (PEO) COATINGS MODIFIED BY СuO NANOPOWDER
The paper presents the results of wear research of contacting pairs with coatings made by plasma electrolytic oxidation and modified by copper oxide (СuO) nanopowder. The authors show experimental data on the determination of the friction ratio in the tested joints. The research goal is to analyze the application of the modified PEO coatings on machine parts made from aluminum alloys to reduce their wear and consequently increase durability. A new method of applying modified PEO coatings has thus been developed. It is demonstrated that the maximum decrease of friction ratio has been observed for the contacting pair «Steel 40Х - PEO coating with through porosity of 12% modified by СuO». The authors have thus established that while applying the recommended electrolyte compositions for plasma electrolytic oxidation (PEO) and arc electrophoresis, double stage processing modes and the solution composition of the copper oxide (СuO) nanopowder, the wear resistance of the tested flexible joints with the PEO coatings modified by nanopowder CuO particles is 1,5…2 times as high, and the friction ratio is 2 times as low in comparison with analogous flexible joints without the hardened layer modification which are considered as a comparison standard. It is proved that the application of PEO coatings modified by CuO nanopowder particles allows increase of flexible joint parts durability.