THE STUDY OF THE PROPERTIES OF MAO-COATINGS FOR CYLINDER GROUP OF THE INTERNAL COMBUSTION ENGINE WHEN THE NANO-ALLOYING
Microarc oxidation (MAO) is one of the promising areas of research in the field of creating coatings with special properties on the surfaces of machine parts. Coatings obtained by the MAO method belong to the field of nanotechnological non-metallic inorganic ones. The main advantages of MAO coatings: wear resistance, hardness, low porosity, heat resistance One of the promising areas for the use of ceramic coatings is a coating for thermal insulation of metal from high temperatures. The aim of the study is to obtain MAO coatings for reflecting heat and reducing temperature, which are affected by high temperatures. For testing, the test specimens were made from a piston alloy by the method of finishing milling. The current lead was made of aluminum wire with surface insulation to exclude the MAO process on its surface. The MAO process is carried out in an electrolytic bath with a cooling water jacket. One end of the current lead from the power source was connected to the bathtub, the second - to a copper rod with a lug to fix the sample to the aluminum wire. A slightly alkaline solution of potassium hydroxide 2g / l KOH in distilled water with the addition of sodium metasilicate in the amount of 9 g / l was used as the base electrolyte. As nano-additives, iron citrate K (Fe (CN)6), vanadium (III) oxide V2O3, sodium tungstate Na2WO4 and copper (II) oxide (copper oxide) CuO were used. The results of the investigations established that the application of ceramic coating on the pistons of ICE petrol and diesel with standard settings and forcing without coating and with a ceramic coating shows an increase in power due to the preservation of heat, i.e. Increase the efficiency of the engine by 8-10%.