Stainless steel electrochemical colouring method

Abstract

This invention is a kind of electro-chemstry staining method of non-corrosive steel. Firstly, pre-treatment for the semi-manufactured non-corrosive steel is essential. Molybdate water solution of 5.0-200 g / L is filled in the electrolytic bath as staining solution, and then the semi-manufactured non-corrosive steel is put into the solution to be stained. The staining electricity should be controlled between 0.02A / square decimeter and 0.6A / square decimeter, while the staining time is between 10 seconds and 60 minutes. At the same time, the temperature should be controlled between 15deg.C and 60 deg.C. After stained, the semi-manufactured non-corrosive steel is water-scrubbed. Then through desiccation, we can get stained non-corrosive steel. To sum up, the staining solution in this invention has no toxicity, has little pollution and power cost, so it does no harm to the workers' health. The technology is easy, and the stained color is stable and has high authenticity. What's more, the cost of the solution is low. You can get multi-colored, homogeneous and highly brightened product.

Description

Technical field [0001] The invention relates to the technical field of stainless steel electrochemical coloring used in construction, home appliances, automobiles and decoration, and specifically refers to a stainless steel electrochemical coloring method. Background technique [0002] The industrial production of colored stainless steel first originated from the British INCO company in 1973. The company mainly impregnates stainless steel in high-concentration chromic acid and sulfuric acid solutions at a medium temperature of 80°C. By controlling the length of the impregnation time, different thicknesses are produced on the surface. Cr 2 O 3 Oxide film. This film itself is translucent, and the light waves reflected on its surface interfere with the light waves that pass through the film and are reflected back from the stainless steel surface. By effectively controlling the film thickness, products with different interference colors can be produce...

AI Technical Summary

Problems solved by technology

The alkaline high-temperature chemical method needs to be colored at a temperature above 100°C, the solution evaporates quickly, the production environment is harsh, and contains toxic substances nitrite and high-concentration hot alkali, which poses a serious threat to the health of workers; the acidic chemical coloring method also needs to be used at 80 For high temperature above ℃, use 2.5mol L -1 Chromic acid+5.0mol·L -1 The mixed acid solution of sulfuric acid is used for coloring treatment, which has problems such as harsh production environment, rapid failure of the treatment solution and high cost of waste acid treatment.

[0005] Whether it is chemical coloring method or electrochemical coloring method, if the coloring process contains chromic acid, there is a pollution problem of hexavalent chromium: a large amount of waste water is formed during the rinsing process, and hexavalent chromium has a great impact on the skin, mucous membranes and respiratory system of the human body. It is irritating and corrosive, has a toxic effect on the central nervous system, and is highly carcinogenic, seriously affecting the health of the staff

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