METHOD OF OBTAINING ELECTRICALLY INSULATING COATING ON SURFACE OF ELECTROMAGNETICALLY CONDUCTING MATERIAL Russian patent published in 2015 - IPC C23C22/56 C23C22/78 

FIELD: chemistry.

SUBSTANCE: invention relates to electric machine engineering and obtaining an electrically insulating coating on the surface of the aluminium winding wire of electric machines operating in extreme conditions with exposure to radiation fields and high temperatures. The method includes oxidising the surface of the aluminium winding wire at 100-200°C in an atmosphere of dry air until formation of a coating layer with thickness of less than 100 nm, which is then treated with a suspension containing mono-substituted aluminium phosphate and fine-grained aluminium oxide. A second coating layer is deposited from a suspension, the ratio of weight parts of said ingredients in which is equal to 1:0.6, at 240-250°C, and an external coating layer is deposited from a suspension in which the ratio of weight parts of said ingredients is equal to 1:0.4, at 250-300°C.

EFFECT: invention enables to obtain an electrically insulating coating on the surface of an aluminium winding wire with improved electrical strength and electrical resistance without using a protective atmosphere or vacuum.