Improving the Performance Properties of Stainless Steel Products by Depositing Modifying Coatings Containing Layers of Copper, Chromium and Zirconium

This article presents the potential for enhancing the corrosion resistance of stainless steel components by depositing modifying coatings containing copper, chromium, and zirconium layers on their surfaces while optimising the deposition process parameters. Coatings with an outer zirconium nitride (ZrN) or chromium nitride (CrN) layer and adhesive-corrosion-resistant Zr–Cu–Zr, Cr–Cu–Cr, and Cu–Zr sublayers were studied. The highest deposition rate of the copper layer was achieved with a copper cathode arc current of Icat = 85 A and a substrate bias voltage of Usub = 100 V. The proposed coatings reduced corrosion intensity by up to 30 times compared to an uncoated sample and up to three times compared to coatings with an adhesive sublayer without copper (zirconium or chromium only). The use of the proposed coatings reduced corrosion intensity by up to 15 times compared to an uncoated sample and up to 1.6 times compared to coatings with an adhesive layer without copper (chromium only). The Cr–Cu–Cr–CrN coating provided the best corrosion resistance in a 3.0% NaCl solution with a calculated corrosion current icor of 0.36 μA/cm2. These results indicate that the inclusion of a copper layer in the adhesive sublayer provides additional corrosion protection. The sample with a Cr–Cu–Cr–CrN coating exhibited better corrosion resistance, but its adhesive bond to the substrate was not very strong. The sample with a Zr–Cu–Zr–ZrN coating demonstrated high adhesive strength with relatively high corrosion resistance.