The present disclosure provides an electroplating method, comprising providing an electroplating solution, wherein the electroplating solution includes an effective microorganisms aqueous solution and metal chloride; disposing a workpiece, wherein at least a part of the workpiece is in contact with the electroplating solution; and performing an electroplating process to electroplate metal of the metal chloride onto the workpiece.

The present disclosure provides an electroplating method, comprising providing an electroplating solution, wherein the electroplating solution includes an effective microorganisms aqueous solution and metal chloride; disposing a workpiece, wherein at least a part of the workpiece is in contact with the electroplating solution; and performing an electroplating process to electroplate metal of the metal chloride onto the workpiece.

The present invention refers to an electroplating composition for depositing a chromium coating on a substrate, the composition including: (i) trivalent chromium ions, (ii) at least one complexing agent for the trivalent chromium ions, and (iii) at least one additive selected from the group consisting of betaines, polymeric glycols, monomeric diols, and mixtures thereof.

The present invention refers to an electroplating composition for depositing a chromium coating on a substrate, the composition including: (i) trivalent chromium ions, (ii) at least one complexing agent for the trivalent chromium ions, and (iii) at least one additive selected from the group consisting of betaines, polymeric glycols, monomeric diols, and mixtures thereof.

The present invention refers to an electroplating bath for electroplating a chromium or chromium alloy layer, the bath comprising trivalent chromium ions, organic carboxylic acid, sulfate ions, sodium conductive ions, and additives in the form of inorganic sulfur compound and boric acid as well as a process using such an electroplating bath.

This cylinder device includes a tubular cylinder that has an opening portion on at least one end side, a metal rod that protrudes through the opening portion of the cylinder, and a sliding contact member that is provided at the opening portion of the cylinder and comes into sliding contact with the rod. A chromium plating film is provided on a surface of the rod. An aspect ratio of an average crystallite diameter in a film thickness direction to an average crystallite diameter in an in-plane direction in the chromium plating film is 0.2 or smaller.

This cylinder device includes a tubular cylinder that has an opening portion on at least one end side, a metal rod that protrudes through the opening portion of the cylinder, and a sliding contact member that is provided at the opening portion of the cylinder and comes into sliding contact with the rod. A chromium plating film is provided on a surface of the rod. An aspect ratio of an average crystallite diameter in a film thickness direction to an average crystallite diameter in an in-plane direction in the chromium plating film is 0.2 or smaller.

An object comprising a chromium-based coating on a substrate is disclosed, wherein the chromium is electroplated from an aqueous electroplating bath comprising trivalent chromium cations, wherein the chromium-based coating comprises 87-98 weight-% of chromium, 0.3-5 weight-% of carbon, and 0.1-11 weight-% of nickel and/or iron, and wherein the chromium-based coating has a Vickers microhardness value of 1000-2000 HV, and wherein the chromium-based coating does not contain chromium carbide. Further is disclosed a method for its production, and an aqueous electroplating bath.

In certain aspects, a coated steel substrate comprises a single or multiple-layer electroplated aluminum coating over a steel substrate. The multiple-layer electroplated aluminum coating comprises one or more porous layers and one or more compact layers. The one or more porous layers comprise a material selected from a group consisting of aluminum and aluminum alloys. The one or more compact layers comprise a material selected from a group consisting of aluminum and aluminum alloys. In certain aspects, a method of depositing a multiple-layer aluminum coating over a steel substrate includes electroplating one or more porous aluminum layers over the steel substrate. The one or more porous aluminum layers comprise a material selected from a group consisting of aluminum and aluminum alloys. One or more compact aluminum layers are electroplated over the steel substrate. The one or more compact aluminum layers comprise a material selected from a group consisting of aluminum and aluminum alloys.

Disclosed is an electrolyte for the electrolytic deposition of chromium as a metal, comprising (a) a chromium (III) salt and (b) metallic chromium, the use of the electrolyte for producing chromium layers on rotationally symmetrical components, in particular gravure printing cylinders, and methods, in which this electrolyte is used.