Solution used for dissolving heat galvanizing alloyed steel plate surface chromates conversion film

Abstract

The invention provides a solution for dissolving chromate transformation film on surface of hot galvanizing alloy steel sheet. The solute of the solution includes (mass percent): alkality buffer agent: 0.01%-1%, alkality inhibitor: 0.01%-1%, the dissolvent is distilled water. The alkality buffer agent includes one of the acid sodium phosphate, superalkali, caustic potash, soda. Said alkality inhibitor is one or more of zinc alkality inhibitor, aluminium alkality inhibitor or magnesium alkality inhibitor. Said zinc alkality inhibitor includes one of hexamethylenetetramine, liquid glass, sodiumdodecylbenzene sulfonate and dodecylsulfate; aluminium alkality inhibitor includes one of the gelatine, amylaceum, prodan, Senegal, sodium silicate; magnesium alkality inhibitor includes one of the prodan, kalii permangana, sodium molybdate, fluor oligosol. The invention resolves deacidizing problem generated during dissolution course of hexavalent chromium, and increases accuracy of result, decreases error of detection for 90% or above, it possesses higher economic profit and social benefit.

Description

technical field [0001] The invention belongs to detection technology, in particular to a solution for dissolving a chromate conversion film on the surface of a hot-dip galvanized alloy steel plate. Background technique [0002] The galvanized layer has a good protective effect on steel products. For steel plates, steel wires, section steel, utensils, castings, fasteners, etc., galvanized is used for corrosion protection. The zinc consumption of galvanized accounts for about 50% of the zinc production. . In order to save zinc resources, at the same time, in order to improve the resistance of hot-dip galvanized steel sheets to harsh corrosion conditions (such as marine atmospheric corrosion), the oxidation resistance at high temperatures (up and down the melting point of zinc), and the hot-dip galvanized products in forming, welding and coating, etc. The performance has been better improved, and people have successfully developed a series of hot-dip galvanized alloy products ...

AI Technical Summary

Problems solved by technology

However, during the detection process, it was found that when the chromate conversion coating was dissolved, elements such as zinc on the substrate were also dissolved one after another, and the potential potential of these elements was different from that of chromium. φ Cr 6 + / Cr 3 + θ = + 1.33 , Therefore, hexavalent chromium is extremely prone to reduction reactions, resulting in large errors in test results and poor reproducibility

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