Nanocomposite anticorrosion coating can be achieved by depositing alternating, multilayers of a cross-linkable polymer and dispersed and aligned inorganic platelets followed by cross-linking of the cross-linkable polymer. The cross-linkable polymer can be an externally cross-linkable polymer that is cross-linked by diffusing a cross-linking agent into the deposited multilayer coating. Alternately, the cross-linkable polymer can be a functionalized cross-linkable polymer that is cross-linked by self-curing, thermal heat curing, or light (e.g., UV) following deposition of the multilayer coating.

A composition for a phosphate film of a Zn electric-plated steel sheet may comprise zinc (Zn), nickel (Ni), and manganese (Mn), wherein a content of Mn is 6 to 8 wt %.

A composition for a phosphate film of a Zn electric-plated steel sheet may comprise zinc (Zn), nickel (Ni), and manganese (Mn), wherein a content of Mn is 6 to 8 wt %.

A method for producing hardened steel components is provided. Sheet bars are cut out from an alloy-galvanized strip made of a hardenable steel alloy and the sheet bars are heated to a temperature that produces a structural change to austenite, preferably to a temperature above the respective Ac3 point. The austenitized sheet bars are then conveyed to a press hardening tool in which the sheet bars are hot formed in a single stroke or multiple strokes by means of an upper and lower tool, wherein the formed sheet bar is cooled against the tools at a speed above the critical cooling rate so that a martensitic hardening occurs.After the galvanization, which can be hot-dip galvanization of the steel strip and before the temperature increase for achieving the austenitization, tin is applied to the surface of the strip or sheet bar.

Disclosed is a substrate pretreatment system, comprising (a) an activating rinse for treating at least a portion of a substrate comprising a dispersion of metal phosphate particles having a D.sub.90 particle size of no greater than 10 μm, wherein the metal phosphate comprises divalent or trivalent metals or combinations thereof; and (b) a pretreatment composition for treating at least a portion of the substrate treated with the activating rinse, comprising zinc ions and phosphate ions, wherein the pretreatment composition is substantially free of nickel. Methods of treating a substrate with the substrate pretreatment system also are disclosed. Substrates treated with the substrate pretreatment system also are disclosed.

Disclosed is a substrate pretreatment system, comprising (a) an activating rinse for treating at least a portion of a substrate comprising a dispersion of metal phosphate particles having a D.sub.90 particle size of no greater than 10 μm, wherein the metal phosphate comprises divalent or trivalent metals or combinations thereof; and (b) a pretreatment composition for treating at least a portion of the substrate treated with the activating rinse, comprising zinc ions and phosphate ions, wherein the pretreatment composition is substantially free of nickel. Methods of treating a substrate with the substrate pretreatment system also are disclosed. Substrates treated with the substrate pretreatment system also are disclosed.

The invention relates to a method for the production and removal of a temporary protective layer for a cathodic coating, particularly for the production of a hardened steel component with an easily paintable surface, wherein a steel sheet made of a hardenable steel alloy is subjected to a preoxidation, wherein said preoxidation forms a FeO layer with a thickness of 100 nm to 1,000 nm and subsequently a melt dip coating is conducted, wherein, during the melt dip coating, a zinc layer is applied having a thickness of 5 to 20 μm, preferably 7 to 14 μm, on each side, wherein the melt dip process and the aluminum content of the zinc bath is adjusted such that, during the melt dip coating, an aluminum content for the barrier layer results of 0.15 g/m.sup.2 to 0.8 g/m.sup.2 and the steel sheet or sheet components made therefrom is subsequently heated to a temperature above the austenitizing temperature and is then cooled at a speed greater than the critical hardening speed in order to cause hardening, wherein oxygen-affine elements are contained in the zinc bath for the melt dip coating in a concentration of 0.10 wt.-% to 15 wt.-% that, during the austenitizing on the surface of the cathodic protective layer, form a thin skin comprised of the oxide of the oxygen-affine elements and said oxide layer is blasted after hardening by irradiation of the sheet component with dry ice particles.

A manufacturing method for steel sheets for containers produces steel sheets with excellent film adhesion qualities. This steel sheet for containers has, on a steel sheet, a chemical conversion coating with a metal Zr content of 1-100 mg/m.sup.2, a P content of 0.1-50 mg/m.sup.2, and an F content of no more than 0.1 mg/m.sup.2, upon which is formed a phenolic resin layer with a C content of 0.1-50 mg/m.sup.2. Moreover, the manufacturing method for steel sheets for containers is a method for obtaining the steel sheet for containers wherein the chemical conversion coating is formed on the steel sheet by subjecting the steel sheet to immersion in or electrolytic treatment with a treatment solution containing Zr ions, phosphoric acid ions, and F ions; and subsequently, the steel sheet upon which the chemical conversion coating has been formed is immersed in, or undergoes topical application of, an aqueous solution containing phenolic resin, then dried.

A manufacturing method for steel sheets for containers produces steel sheets with excellent film adhesion qualities. This steel sheet for containers has, on a steel sheet, a chemical conversion coating with a metal Zr content of 1-100 mg/m.sup.2, a P content of 0.1-50 mg/m.sup.2, and an F content of no more than 0.1 mg/m.sup.2, upon which is formed a phenolic resin layer with a C content of 0.1-50 mg/m.sup.2. Moreover, the manufacturing method for steel sheets for containers is a method for obtaining the steel sheet for containers wherein the chemical conversion coating is formed on the steel sheet by subjecting the steel sheet to immersion in or electrolytic treatment with a treatment solution containing Zr ions, phosphoric acid ions, and F ions; and subsequently, the steel sheet upon which the chemical conversion coating has been formed is immersed in, or undergoes topical application of, an aqueous solution containing phenolic resin, then dried.

A method of producing a hot-dip Zn alloy-plated steel sheet includes: dipping a base steel sheet in a hot-dip Zn alloy plating bath to form a hot-dip Zn alloy plating layer on a surface of the base steel sheet; and contacting an aqueous solution containing a water-soluble corrosion inhibitor with a surface of the hot-dip Zn alloy plating layer to cool the base steel sheet and the hot-dip Zn alloy plating layer having a raised temperature through formation of the hot-dip Zn alloy plating layer. A temperature of the surface of the hot-dip Zn alloy plating layer when the aqueous solution is to be contacted with the surface of the hot-dip Zn alloy plating layer is equal to or more than 100° C. and equal to or less than a solidifying point of the plating layer. The aqueous solution containing the water-soluble corrosion inhibitor satisfies the Equation [{(Z.sub.0−Z.sub.1)/Z.sub.0}100≧201.