Structure, Oxidation Resistance, and Corrosion and Tribological Characteristics of Coatings Produced by Electrospark Deposition of Ni and Al Powders on Steel 35

Nickel and aluminum powders have been deposited for the first time on steel 35 by electrospark deposition. We have studied the effect of the ratio of the Ni and Al powders in the anodic mixture on the structure, oxidation resistance, and corrosion behavior of the coatings and also on their friction coefficient and wear resistance. The results demonstrate that, as the fraction of aluminum powder in the anodic mixture increases from 30 to 70 at %, the average aluminum content of the coatings increases steadily from 39 to 63 at %, whereas the nickel content decreases from 46 to 26 at %. The use of such coatings allows the oxidation resistance of steel 35 parts at a temperature of 700°C to be raised 13 to 34 times. The most aluminum rich coating has been shown to have the highest hardness, wear resistance, and heat resistance.