Characteristics and properties of Co–Cr alloy coatings prepared by electrodeposition

Abstract

Two different ways were used for preparing the electrodeposition baths. In the first bath, different concentrations of cobalt sulphate (up to 6 g L -1 ) and one complexing agent were employed. In the second bath, two different complexing agents and a constant concentration of cobalt sulphate were used. The results showed that the microstructure of the coatings was changed from amorphous to nano-crystalline by enhancing cobalt sulphate concentration in the bath No. 1. Current efficiency and thickness of the alloy coatings obtained from bath No. 2 were higher than those deposited from bath No. 1. However, reducing the bath temperature or raising the current density decreased the current efficiency, while increased Cr content and hardness of alloy coatings. The Co-29.3 wt-%Cr electrodeposit obtained from bath No. 2 at the optimum condition had better corrosion and wear resistance than Co-Cr and Cr films produced from bath 1, as well as the steel substrate.

Experimental study on wear failure of spindle hook teeth of cotton picker

“…1 and 3 spindle hook tooth coatings at this time. The convex hull is caused by the partially cleaned surface of the spindle hook teeth before electroplating or impurity-polluted plating solution (Yu et al, 1990;Mahdavi et al, 2020). The surface of the No.…”

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“…Corrosion resistance properties results are given in Tables 5 and 6, and it can be observed that the incorporation of epoxy resin and acrylic grafting polymers helped to develop a coating with improved salt spray resistance and humidity. The corrosion resistance properties of the developed coating were optimised with the increase of epoxy content in the coatings [15,[24][25][26][27][28].…”

Impact of Different Atmospheres on Oxidation and Electrical Performance of a Solid Oxide Fuel Cell Interconnect with Co-Containing Protective Coating

“…For instance, Guo et al fabricated a Cu- or La-doped Co–Mn coating on 430 SS by the method of the high-energy micro-arc alloying process to improve high-temperature oxidation resistance and electrical properties. Mahdavi et al prepared Co–Cr alloy coatings onto 316L SS via an electrodeposition approach to intensify corrosion and wear resistance of 316L SS. Jia et al reported a Mn–Co metallic coating on SUS430 steel through physical vapor deposition and oxidized in humidified H 2 /N 2 to increase the long-term performance.…”

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