Disclosed is a system for treating a surface of a multi-metal article. The system includes first and second and/or third conversion compositions for contacting at least a portion of the surface. The first conversion composition includes phosphate ions and zinc ions and is substantially free of fluoride. The second conversion composition includes a lanthanide series metal cation and an oxidizing agent. The third conversion composition includes an organophosphate compound, an organophosphonate compound, or combinations thereof that optionally may include at least one transition metal. Methods of treating a multi-metal article using the system also are disclosed. Also disclosed are substrates treated with the system and method.

Disclosed is a method of treating a substrate, comprising contacting at least a portion of the substrate surface with a first composition comprising a lanthanide source and an oxidizing agent. A substrate obtainable by the methods also is disclosed.

Described herein is a method for phosphating of a metallic surface, wherein a metallic surface, optionally after cleaning and/or activation, is first treated with an acidic, aqueous, substantially nickel-free phosphating composition that includes zinc ions, manganese ions, iron(III) ions and phosphate ions, and is thereafter optionally rinsed and/or dried. Also described herein are a corresponding phosphating composition and a correspondingly phosphate-coated metallic surface.

The present invention provides an aqueous passivation composition for the treatment of zinc or zinc alloy coatings, comprising: i) phosphoric acid; ii) at least one water-soluble polyphosphonic acid or a water-soluble salt thereof, iii) at least one divalent metal cation (M.sup.2+); and, iv) at least one water-soluble or water-dispersible fluoroacid or a salt thereof, wherein said fluoroacid is defined by the following general empirical formula (II):

H.sub.pT.sub.qF.sub.rO.sub.s   (II)

wherein: each of q and r represents an integer from 1 to 10; each of p and s represents an integer from 0 to 10; and, T represents an element selected from the group consisting of Ti, Zr, Hf, Si, Sn, Al, Ge, and B.

A surface-treated metal sheet includes a steel sheet, a coating layer containing zinc formed on the steel sheet and a conversion coating formed on the coating layer, wherein the conversion coating contains an organosilicon compound, a phosphate compound and a fluorine compound, and when the surface roughness in a rectangular area with a side of 1 μm on the surface of the conversion coating is represented by an arithmetic mean height of the scale limited surface Sa, a maximum height of the scale limited surface Sz, and a root mean square height of the scale limited surface Sq, one or more conditions of an arithmetic mean height of the scale limited surface Sa being 0.1 to 10 nm, a maximum height of the scale limited surface Sz being 1 to 1,000 nm, and a root mean square height of the scale limited surface Sq being 0.1 to 100 nm are satisfied.

A method includes providing an electrically conductive mandrel having an outer surface layer comprising a preformed pattern. The metallic article is electroformed. The metallic article includes a plurality of electroformed elements formed in the preformed pattern on the outer surface layer of the mandrel. The plurality of electroformed elements have a first side adjacent to the outer surface layer of the mandrel and a second side. The metallic article is separated from the mandrel. The plurality of electroformed elements are interconnected such that the metallic article forms a unitary, free-standing piece. A solution is applied to create a blackening of the first side of the plurality of electroformed elements.

The present disclosure relates to a method of chemical pretreatment and selective phosphation of a composite metal construction comprising at least a portion made of aluminum and at least a portion made of zinc and optionally a further portion made of iron, which includes (I) treating the composite metal construction with an aqueous zinc phosphation composition that results in the formation of a surface-covering crystalline zinc phosphate layer and thenwith an intervening water rinse operation (II) applying an aqueous acidic passivation composition,

The present disclosure also relates to a corresponding zinc phosphation composition, to a concentrate for production thereof, to a corresponding composite metal construction and to a method of using thereof.

Disclosed herein is a first composition comprising a trivalent chromium cation and an aqueous carrier. Also disclosed herein is a second composition comprising a permanganate anion and an aqueous carrier. Also disclosed herein is a system for treating a metal substrate comprising a first composition comprising a trivalent chromium cation and an aqueous carrier and optionally a second composition comprising a permanganate anion and an aqueous carrier. Also disclosed herein is a method of treating a metal substrate comprising contacting at least a portion of the substrate surface with a first composition comprising a trivalent chromium cation and an aqueous carrier and optionally contacting at least a portion of the substrate surface with a second composition comprising a permanganate anion and an aqueous carrier.

A method includes providing an electrically conductive mandrel having an outer surface layer comprising a preformed pattern. The metallic article is electroformed. The metallic article includes a plurality of electroformed elements formed in the preformed pattern on the outer surface layer of the mandrel. The plurality of electroformed elements have a first side adjacent to the outer surface layer of the mandrel and a second side. A solder is plated on the second side of the plurality of electroformed elements while on the mandrel. The metallic article is separated from the mandrel. The plurality of electroformed elements are interconnected such that the metallic article forms a unitary, free-standing piece. A solution is applied to create a blackening of the first side of the plurality of electroformed elements. The solder on the second side of the plurality of electroformed elements is not blackened.

This Sn-plated steel sheet includes: a base plated steel sheet having a steel sheet, and a Sn-plated layer on at least one surface of the steel sheet; and a film layer which contains a zirconium oxide and a tin oxide and is positioned on the base plated steel sheet. An adhesion amount of Sn per surface of the Sn-plated steel sheet is 0.1 g/m.sup.2 or more and 15 g/m.sup.2 or less, an amount of the zirconium oxide in the film layer is in a range of 1 mg/m.sup.2 or more and 30 mg/m.sup.2 or less in terms of an amount of metal Zr, a peak position of a binding energy of Sn3d.sub.5/2 of the tin oxide by X-ray photoelectron spectroscopy in the film layer is within a range of 1.4 eV or more and less than 1.6 eV from a peak position of a binding energy of metal Sn, and a quantity of electricity required for reduction of the tin oxide is in a range of more than 5.0 mC/cm.sup.2 and 20 mC/cm.sup.2 or less.