INFLUENCE OF THE POROSITY OF A PLASMA-ELECTROLYTIC COATING ON THE CORROSION RESISTANCE OF D16 ALLOY

We study the effect of the coating thickness on the corrosion resistance and porosity of oxide-ceramic coatings on D16 alloy. The coatings were synthesized in an alkaline solution for 10, 60, and 120 min at a current density of 10 A/dm(2). As a result, the coatings with thicknesses of similar to 8-12, 50-70, and 80-120 mu m, respectively, were formed on the surface of the alloy. The corrosion resistance of the coatings was investigated in a medium of weakly acid rain and in a 3% NaCl solution in water. We established the correlation between the porosity and corrosion resistance of the coatings. The oxide-ceramic coatings synthesized on D16 alloy for 60 min have the lowest porosity and the highest corrosion resistance.