Abstract: Systems, methods, and devices for electrodeposition of tungsten disulfide coatings are described. Electrodeposition of the coating includes coupling a power source to a surface of a substrate and to an electrode, immersing the surface of the substrate and the electrode into an aqueous solution, and forming a tungsten disulfide layer on the surface of the substrate. The surface is conductive, and the power source is a DC power source. The aqueous solution includes sodium metabisulfite, sodium tungstate, a surfactant, and a pH modifier. The tungsten disulfide layer is formed by applying, via the power source, a pulsed current to the surface of the substrate and the electrode in the aqueous solution and maintaining the pulsed current for a predetermined period of time.

Abstract: A method of forming a lubricant coating, a method of coating a bearing surface with a lubricant coating, and a vehicle including a bearing including a lubricant coating. A substrate, such as a bearing, including a surface and an electrode are immersed in an electrolyte bath. The electrolyte bath includes an aqueous electrolyte solution including sodium metabisulfite (Na2S2O5), sodium molybdate (Na2MoO4·2H2O), a pH modifier, an anionic surfactant, and water. A first pulsed direct current is applied through the aqueous electrolyte solution using a direct current power supply and a molybdenum disulfide (MoS2) layer is formed on the surface of the substrate.

Abstract: A method of coating an automotive part for an electric drive unit is provided. The method comprises providing a part comprising a body having an outer surface and introducing the part in an aqueous coating solution comprising sodium metabisulfite and citric acid to form residual oxides on the outer surface defining a sample-water interface. The method further comprises emitting ultrasonic waves in the coating solution to generate acoustic cavitation activity at the sample-water interface and continuously form oxygen and hydrogen species. The citric acid arranged to activate the outer surface to allow for the reaction with the oxygen and hydrogen species forming iron hydroxide. The sodium metabisulfite arranged to react with the iron hydroxide generating iron oxysulfide such that the iron oxysulfide reacts with the oxygen and hydrogen species to produce iron oxide and iron sulfide on the outer surface defining a black oxide coating.