METHOD OF RESTORING WORN-OUT INNER WORKING SURFACES OF CYLINDER LINERS OF INTERNAL COMBUSTION ENGINES TO NOMINAL SIZE Russian patent published in 2025 - IPC B23P6/02 F02F1/16 C23C24/04 C25D11/06 

FIELD: chemistry.

SUBSTANCE: invention relates to repair and can be used to restore worn-out working surface and cylinder liners of internal combustion engines to nominal size. In the method, cold gas-dynamic sputtering is carried out by heating compressed gas and feeding it into a brass tube and into an angular nozzle, in which the gas flow is turned through 90°, wherein powder of sputtered material is added to gas flow from feeder. Particles of said material are accelerated in gas flow and via additional Laval nozzle to compensate for loss in velocity and directed to surface of processed article. Sputtered material used is aluminium powder, which is fed 0.3–0.4 g/s while heating air to 300 °C production of sputtered layer with thickness compensating for wear with allowance of 50 mcm for machining, then, extra micro-arc oxidation (MAO) is carried out to obtain a hardened layer with depth of 80–100 mcm and finish honing to roughness of not more than Ra 0.63 mcm and thickness of the hardened layer of 30–50 mcm.

EFFECT: obtaining a coating with wear resistance equal to or exceeding that of the working surface of the new cylinder liner, and tribological properties similar to the standard friction pair liner-piston ring.

1 cl, 2 dwg