The present invention relates to a method for the cleaning and/or anti-corrosion pretreatment of a plurality of components in series, in which the components of the series are at least partially composed of zinc-coated (ZM) steel. After a cleaning stage and before further cleaning and/or anti-corrosion pretreatment, the components pass through a treatment stage for improving the wettability of the zinc-coated (ZM) steel surfaces in which at least the surfaces of the zinc-coated (ZM) steel of the components are brought into contact with an aqueous medium which contains at least one builder which is a salt of a Lewis acid-base pair in which the Lewis acid is selected from Li.sup.+, Na.sup.+, K.sup.+, Ca.sup.2+, Mg.sup.2+ or Al.sup.3+, and the Lewis base is selected from anions of a polyprotic Br?nsted acid.

Provided is a chemical conversion agent that, with respect to an aluminum metal material, etc., contributes to superior corrosion and moisture resistance, contributes to superior adhesion with a laminate film, and contributes to superior hydrofluoric acid and alkali resistance. The chemical conversion agent includes: one or more type of metal element (A) selected from a group comprising of zirconium, titanium, and hafnium; vanadium element (B); and a resin (C). The resin (C) includes a polyvinyl alcohol resin (C1). The ratio (Wa/Wb) of the weight-based total content (Wa) of the metal element (A) relative to the weight-based content (Wb) of vanadium element (B) is 0.1-15, and the ratio ((Wa+Wb)/Wc1) of the weight-based total content (Wa+Wb) of the metal element (A) and the vanadium element (B) relative to the weight-based total content (Wc1) of the polyvinyl alcohol resin (C1) is 0.25-15.

Provided is a chemical conversion agent that, with respect to an aluminum metal material, etc., contributes to superior corrosion and moisture resistance, contributes to superior adhesion with a laminate film, and contributes to superior hydrofluoric acid and alkali resistance. The chemical conversion agent includes: one or more type of metal element (A) selected from a group comprising of zirconium, titanium, and hafnium; vanadium element (B); and a resin (C). The resin (C) includes a polyvinyl alcohol resin (C1). The ratio (Wa/Wb) of the weight-based total content (Wa) of the metal element (A) relative to the weight-based content (Wb) of vanadium element (B) is 0.1-15, and the ratio ((Wa+Wb)/Wc1) of the weight-based total content (Wa+Wb) of the metal element (A) and the vanadium element (B) relative to the weight-based total content (Wc1) of the polyvinyl alcohol resin (C1) is 0.25-15.

Disclosed are pretreatment compositions and associated methods for treating metal substrates with pretreatment compositions, including ferrous substrates, such as cold rolled steel and electrogalvanized steel. The pretreatment composition includes: a Group IIIB and/or IVB metal; free fluoride; and molybdenum. The methods include contacting the metal substrates with the pretreatment composition.

Disclosed are pretreatment compositions and associated methods for treating metal substrates with pretreatment compositions, including ferrous substrates, such as cold rolled steel and electrogalvanized steel. The pretreatment composition includes: a Group IIIB and/or IVB metal; free fluoride; and molybdenum. The methods include contacting the metal substrates with the pretreatment composition.

Provided herein is a process for the pretreatment of workpieces having a surface of aluminum or aluminum alloys for noncutting forming and/or joining by welding or adhesive bonding to similarly pretreated, precoated workpieces, or to precoated parts. The parts are composed of steel, galvanized steel, and/or alloy-galvanized steel. Further provided herein is a subsequent permanent corrosion-protecting treatment by phosphating, by means of a chromium-free conversion treatment, by application of primer, or by surface coating, wherein the workpieces are a) pickled by means of an aqueous, acidic solution comprising mineral acid by dipping or spraying, b) rinsed with water, and c) brought into contact with an aqueous, acidic, chromium-free solution comprising Zr as complex fluoride and Mo as molybdate by application by dipping or spraying. After subsequent drying, a layer weight from 2 to 15 mg/m.sup.2 of Zr and Mo is formed.

Provided herein is a process for the pretreatment of workpieces having a surface of aluminum or aluminum alloys for noncutting forming and/or joining by welding or adhesive bonding to similarly pretreated, precoated workpieces, or to precoated parts. The parts are composed of steel, galvanized steel, and/or alloy-galvanized steel. Further provided herein is a subsequent permanent corrosion-protecting treatment by phosphating, by means of a chromium-free conversion treatment, by application of primer, or by surface coating, wherein the workpieces are a) pickled by means of an aqueous, acidic solution comprising mineral acid by dipping or spraying, b) rinsed with water, and c) brought into contact with an aqueous, acidic, chromium-free solution comprising Zr as complex fluoride and Mo as molybdate by application by dipping or spraying. After subsequent drying, a layer weight from 2 to 15 mg/m.sup.2 of Zr and Mo is formed.

A plated steel sheet (1) includes: a steel sheet (2); a pre-plating layer (3) on at least one surface of the steel sheet (2), the pre-plating layer (3) containing Al, Cu, In, Zn, Sn, or Sb, or any combination thereof; and a plating layer (4) of a ZnNi alloy on the pre-plating layer (3), a Ni content of the ZnNi alloy being 5 mass % to 15 mass %. A coating weight of the pre-plating layer (3) is 0.5 g/m.sup.2 or more, and a coating weight of the plating layer (4) is 5 g/m.sup.2 or more.

A plated steel sheet (1) includes: a steel sheet (2); a pre-plating layer (3) on at least one surface of the steel sheet (2), the pre-plating layer (3) containing Al, Cu, In, Zn, Sn, or Sb, or any combination thereof; and a plating layer (4) of a ZnNi alloy on the pre-plating layer (3), a Ni content of the ZnNi alloy being 5 mass % to 15 mass %. A coating weight of the pre-plating layer (3) is 0.5 g/m.sup.2 or more, and a coating weight of the plating layer (4) is 5 g/m.sup.2 or more.

A method for the manufacture of a substrate provided with a chromium VI-free and a cobalt-free passivation by the application of a first acidic passivation and a second alkaline passivation, containing a silane-modified and/or a siloxane modified silicate, with which an improved protection against corrosion is achieved, an aqueous, acidic composition for passivating and a passivated substrate, and a device for applying the passivation.