Method for detecting service life of steel plate chromium plating solution

Abstract

The invention relates to a method for detecting the service life of a steel plate chromium plating solution, the method sequentially comprises the following steps: establishing a relation model which comprises a first relation model and a second relation model; taking chromium plating solutions of the unit at different times or at different stages; adding hydrogen peroxide into the chromium plating solution to obtain a first solution; adding ammonia water or sodium carbonate into the first solution for pH value characteristic regulation and control, gradually increasing the pH value, and controlling the numerical range of the pH value of the first solution to be 3-6; carrying out particle size analysis and centrifugal sedimentation on the first solution to obtain sediment of impurity ions, and drying and weighing the sediment; if conditions are met, obtaining the service life of the corresponding chromium plating solution according to the first relation model; and if the pH value of the first solution in the numerical range cannot meet the conditions in the first relation model, adding the mixed solution into the first solution and regulating to obtain a second solution with the pH value of 2, and obtaining the service life of the chromium plating solution according to the second relation model.

Description

technical field [0001] The invention relates to a steel plate chrome plating solution, in particular to a method for detecting the service life of a steel plate chrome plating solution. Background technique [0002] Chromium-plated steel plate is an economical tank material that deposits a layer of metal chromium and chromium oxide film on the surface of cold-rolled steel plate by electrolytic chromate treatment. The chemical composition of the surface of chrome-plated steel plate is stable, and the chromium ion dissolved from the surface film is extremely small. Because of its non-toxic surface, it is widely used in packaging industries such as food cans. Chromium-plated steel plate also has the advantages of less plating, low cost, strong adhesion, good paintability, good temperature resistance, high sulfur resistance, high alkali resistance, etc. It can also be used in bicycle parts, household electrical appliances, office Supplies, building materials parts, auto parts a...

AI Technical Summary

Problems solved by technology

see figure 1 , as the production progresses, the impurity ions in the plating solution gradually gather and their content increases, which greatly affects the cleanliness of the plating solution, and even affects the surface quality of chrome-plated steel sheets

When the content of impurity ions reaches a certain concentration, the coating on the chrome-plated steel plate will have many quality problems such as blooming, yellowing, darkening, and streaks. See figure 2 , when the concentration of impurity ions in the metal chromium section solution is high, there are fine particle defects on the surface of the chrome-plated steel plate

At the same time, as the content of impurity ions increases, the voltage of the electroplating tank increases and the resistance of the plating solution increases

[0004] At present, most chrome-plated steel plate manufacturers generally follow the principle of "change once every three months and change every six months" for the management of plating solution discharge. However, in the actual production process, the service life of the chromium plating solution cannot be accurately judged. The chromium plating solution is often processed and replaced when unqualified chrome-plated steel sheets are produced.

In addition, the chromium plating solution contains hexavalent chromium and fluorine ions, so its discharge requirements are very strict, which also brings more difficulties to manufacturers

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