METHOD FOR FORMING PROTECTIVE COATINGS ONTO SURFACE OF METALS AND ALLOYS Russian patent published in 2002 - IPC

FIELD: electrochemical treatment of metals and alloys for forming on their surface corrosion-, thermo- and wear-resistant coatings and for imparting to them protective dielectric and decorative properties, possibly in machine engineering, radioelectronics, chemical industry , medicine, aircraft manufacture and other industry branches. SUBSTANCE: method comprises steps of microarc oxidizing by means of device including electrolyte and porous screen through which liquid electrolyte is supplied; applying voltage between treated portion and porous screen; supplying electrolyte through porous screen at flowrate (4 - 8) l/min; performing treatment for (3 - 10) min at voltage increased up to 190 V and electric current density increased up to 5 A/sq.dm. Motion speed vector and vector of maximum thickness gradient of porous screen are normal one relative to another and they depend upon predetermined relation. EFFECT: possibility for controlling thickness of coating, lowered volume of consumed electrolyte and electric current value, enhanced quality of protective coating.