Methods for treatment shaped bodies are described herein. The methods generally include contacting at least one shaped body with an aqueous acidic composition to form a conversion layer on a surface of the at least one shaped body, wherein the surface includes iron or steel and a carbon content in a range of 0 to 2.06 wt. % and a chrome content in a range of 0 to <10 wt. % and wherein the surface is optionally galvanized or alloy galvanized. The aqueous acidic composition includes water; from 2 to 500 g/L oxalic acid; and from 0.01 to 20 g/L of at least one catalyst based on guanidine, nitrate or combinations thereof, wherein a pickling removal of the aqueous acidic composition is in a range of 1 to 6 g/m.sup.2.

Disclosed herein is a method of pretreatment of a metallic substrate for a subsequent metal cold forming process. The method includes at least steps (1) and (2), namely providing at least one substrate having at least one surface at least partially made of at least one metal (step (1)), contacting the at least one surface of the substrate provided in step (1) with an aqueous lubricant composition (B) (step (2)), where the aqueous lubricant composition (B) includes besides water at least constituents (b1) to (b4) and optionally (b5).

Further disclosed herein are a pretreated metallic substrate obtained by the method, a method of cold forming of a metallic substrate, and an aqueous lubricant composition (B).

The present invention relates to a method for adjusting a passivation composition by determining the redox potential of a passivation composition as well as to a method for passivating metallic substrates by treatment with a passivation composition.

The present invention provides a chemical conversion liquid for zinc or zinc alloy bases, which contains 2-200 mmol/L of trivalent chromium ions, 1-300 mmol/L of zirconium ions and at least one component selected from among fluorine ions, a water-soluble carboxylic acid and a salt thereof, and which does not contain Co ions and hexavalent chromium ions.

The present invention provides a chemical conversion liquid for zinc or zinc alloy bases, which contains 2-200 mmol/L of trivalent chromium ions, 1-300 mmol/L of zirconium ions and at least one component selected from among fluorine ions, a water-soluble carboxylic acid and a salt thereof, and which does not contain Co ions and hexavalent chromium ions.

A highly reactive conversion coating chemistry is used during CAVF processing of high hardness steel alloys such as AMS 6509 and AMS 6517 steel alloys. This chemistry produces a hard, thin, black conversion coating that is not fully rubbed off by the media during the CAVF process. Distressed material regions on the surface of the alloys are not susceptible to forming the conversion coating and remain white. Visual inspection for the presence of such regions is facilitated.

A highly reactive conversion coating chemistry is used during CAVF processing of high hardness steel alloys such as AMS 6509 and AMS 6517 steel alloys. This chemistry produces a hard, thin, black conversion coating that is not fully rubbed off by the media during the CAVF process. Distressed material regions on the surface of the alloys are not susceptible to forming the conversion coating and remain white. Visual inspection for the presence of such regions is facilitated.

Provided are a treatment liquid for a trivalent chromium conversion coating, achieving excellent corrosion resistance and scratch resistance without containing a cobalt compound, with high stability and adequate consideration for environmental issues; and a method for treating a metal substrate using the same. Provided is a treatment liquid for a trivalent chromium conversion coating on the surface of a metal substrate comprising: a trivalent chromium compound; titanium lactate; one or more compounds of transition metal other than cobalt; two or more organic acids or organic acid salts, and at least one ion species selected from chloride ions, nitrate ions, and sulfate ions; but no cobalt compound.

Provided are a treatment liquid for a trivalent chromium conversion coating, achieving excellent corrosion resistance and scratch resistance without containing a cobalt compound, with high stability and adequate consideration for environmental issues; and a method for treating a metal substrate using the same. Provided is a treatment liquid for a trivalent chromium conversion coating on the surface of a metal substrate comprising: a trivalent chromium compound; titanium lactate; one or more compounds of transition metal other than cobalt; two or more organic acids or organic acid salts, and at least one ion species selected from chloride ions, nitrate ions, and sulfate ions; but no cobalt compound.

Provided is a zinc-based plated steel sheet having a post-treated coating filmed thereon including: a steel sheet; a zinc plated layer formed on the steel sheet; and a post-treated coating formed on the plated layer, wherein the atomic ratio (O/M) of oxygen (O) to metals (M) contained in the post-treated coating is greater than 2 and less than 20, and a method for post-treating a zinc-based plated steel sheet. According to this, the zinc-based plated steel sheet having the post-treated coating formed thereon has the effects excellent in lubricity, weldability, adhesiveness, film-removing property and paintability. As the method of post-treating a zinc-based plated steel sheet of the present invention employs a simple coating method irrespective of the kind of plating layer, the process is simple and economical and the process operation cost is low.