A method includes providing a workpiece with at least one surface having an anodized aluminum coating and a trivalent chromium sealant. The at least one surface of the workpiece is submerged in a post-treatment sealant solution for 0.5 to 20 minutes. The sealant composition consists essentially of a corrosion inhibitor formulation, a water soluble polymer, an organic complexing agent, and an oxidant. The corrosion inhibitor formulation is formulated from at least one anodic corrosion inhibitor compound, at least one cathodic corrosion inhibitor compound, or a combination thereof. A concentration of each of the corrosion inhibitor formulation, the water soluble polymer, the organic complexing agent, and the oxidant is each in a range of 1-50 mM.

A method includes providing a workpiece with at least one surface having an anodized aluminum coating and a trivalent chromium sealant. The at least one surface of the workpiece is submerged in a post-treatment sealant solution for 0.5 to 20 minutes. The sealant composition consists essentially of a corrosion inhibitor formulation, a water soluble polymer, an organic complexing agent, and an oxidant. The corrosion inhibitor formulation is formulated from at least one anodic corrosion inhibitor compound, at least one cathodic corrosion inhibitor compound, or a combination thereof. A concentration of each of the corrosion inhibitor formulation, the water soluble polymer, the organic complexing agent, and the oxidant is each in a range of 1-50 mM.

Provided is a surface treatment method of metal powder and surface passivated metal powder. Herein, the surface treatment method uses passivation solution to treat the metal powder, to form a passivation film on the surface of the metal powder; the passivation solution passes through the metal powder by a flowing method; and the average particle size of the metal powder is 0.1?100 ?m. A problem in the prior art that the metal powder is easily oxidized is solved, and it is suitable for the field of metal anti-oxidation.

Provided is a surface treatment method of metal powder and surface passivated metal powder. Herein, the surface treatment method uses passivation solution to treat the metal powder, to form a passivation film on the surface of the metal powder; the passivation solution passes through the metal powder by a flowing method; and the average particle size of the metal powder is 0.1?100 ?m. A problem in the prior art that the metal powder is easily oxidized is solved, and it is suitable for the field of metal anti-oxidation.

A method includes providing a workpiece with at least one surface having an anodized aluminum coating and a trivalent chromium sealant. The at least one surface of the workpiece is submerged in a post-treatment sealant solution for 0.5 to 20 minutes. The sealant composition consists essentially of a corrosion inhibitor, an organic complexing agent, and an oxidant.

A treatment agent for chromium-free insulating coating formation suitable for forming an insulating coating on a surface of a grain-oriented electrical steel sheet. The treatment agent includes components (A), (B), (C), and (D). The component (B) is contained in an amount of 50 to 150 parts by mass on a SiO.sub.2 solid basis, and the component (C) is contained in an amount of 5.0 parts by mass or more on an elemental metal basis, the amounts being based on 100 parts by mass, on a solid basis, of the component (A). The component (D) is contained in an amount that a molar ratio of M.sup.2+ and M.sup.3+, each being a metal element in the treatment agent for chromium-free insulating coating formation, to a phosphorus element P satisfies a specified relationship, and the treatment agent for chromium-free insulating coating formation has a pH of less than 4.5.

A treatment agent for chromium-free insulating coating formation suitable for forming an insulating coating on a surface of a grain-oriented electrical steel sheet. The treatment agent includes components (A), (B), (C), and (D). The component (B) is contained in an amount of 50 to 150 parts by mass on a SiO.sub.2 solid basis, and the component (C) is contained in an amount of 5.0 parts by mass or more on an elemental metal basis, the amounts being based on 100 parts by mass, on a solid basis, of the component (A). The component (D) is contained in an amount that a molar ratio of M.sup.2+ and M.sup.3+, each being a metal element in the treatment agent for chromium-free insulating coating formation, to a phosphorus element P satisfies a specified relationship, and the treatment agent for chromium-free insulating coating formation has a pH of less than 4.5.

The present invention addresses the problem of providing a surface adjuster with which a chemical conversion coating having a surface state in which zinc phosphate crystals are densely packed can be formed even when the zinc phosphate chemical conversion treatment step is performed in a short time. The problem is solved by a surface adjuster for zinc phosphate chemical conversion treatment, which contains: a zinc-containing phosphate (A); an alkali salt (B) of a copolymer (b2) containing a 2-acrylamide-2-methylpropane sulfonic acid unit (b1), in which a ratio of (b1) in the copolymer (b2) is 7.5% by mass to 40.0% by mass; and an aqueous medium (C).

The present invention addresses the problem of providing a surface adjuster with which a chemical conversion coating having a surface state in which zinc phosphate crystals are densely packed can be formed even when the zinc phosphate chemical conversion treatment step is performed in a short time. The problem is solved by a surface adjuster for zinc phosphate chemical conversion treatment, which contains: a zinc-containing phosphate (A); an alkali salt (B) of a copolymer (b2) containing a 2-acrylamide-2-methylpropane sulfonic acid unit (b1), in which a ratio of (b1) in the copolymer (b2) is 7.5% by mass to 40.0% by mass; and an aqueous medium (C).

The purpose of the present invention is to provide a water-soluble finishing agent for a trivalent chromium chemical conversion coating film, which has low insulation, no problems with tightening properties, outstanding gloss and high corrosion resistance, and can obtain a trivalent chromium chemical conversion coating film, especially a black trivalent chromium chemical conversion coating film, having few scratches and flaws. The finishing agent for a trivalent chromium chemical conversion coating film is characterized by containing a trivalent chromium source, a phosphate ion source, a zinc ion source, a chelating agent which can form a complex with trivalent chromium, and a non-ionic water-soluble polymer compound selected from a group comprising poly(vinyl alcohol) and derivatives thereof, poly(vinyl pyrrolidone) and derivatives thereof, poly(alkylene glycol)s and derivatives thereof, and cellulose ethers and derivatives thereof.