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Deactivator Component Conversion Film General Treatment
- Oct 31, 2017 -

No matter what kind of metal to use chromium-free passivation agent for surface treatment, want to get good results, then the metal surface cleaning must be. Because the parts are sent to the workshop are generally there are a variety of wear marks, pits, burrs, scratches and other defects, there are some traces of lubricants or varying degrees of covering abrasives and dirt. If it is not cleaned before the surface transformation film treatment, it will be exposed after conversion, affecting the performance of the membrane. So the cleaning surface is the chemical conversion film processing process of the necessary process.

The metal surface treatment includes mechanical treatment and chemical treatment. Mechanical processing is divided into grinding wheel grinding, mechanical polishing, sandblasting and so on. Chemical treatment methods are acidic degreasing, alkaline degreasing, emulsion degreasing, solvent degreasing, electrolytic degreasing, ultrasonic degreasing, electrolytic polishing, chemical polishing and so on.

Here to tell you about the metal surface conversion film processing of the three purposes of it

1, to ensure that the coating has good corrosion resistance and can and the substrate surface has a good adhesion.

 Metal surfaces are generally present in scale, rust, and solder. Oil, water, dust and other effects of coating and substrate surface adhesion and corrosion resistance of things. The purpose of surface treatment is to thoroughly clean these pollutants, thereby enhancing the film adhesion and corrosion resistance.

2, to improve the appearance of the coating quality

 The surface roughness of the substrate will be different because of the different nature of the material processing methods lead to different surface conditions are not the same. Like the common method of casting the surface of the casting rough and resin sand molding casting surface smooth. This can be done using a mechanical elimination method to eliminate the defects produced by the machining of the base machine and to create the desired surface roughness for the coating. Like large-scale welding parts used in the overall sandblasting treatment, the use of hammer flat method to make the overall sheet metal pieces of uneven defects. When the substrate has a flat surface after you want to get high-quality coating, which also depends on the performance of the coating described and the correct construction methods.

3, to improve the coating adhesion and corrosion resistance

This is like steel parts will be in the metal surface treatment before the coating of phosphating treatment, and for the aluminum parts of the oxidation treatment, thereby enhancing the coating and the workpiece matrix adhesion and enhance the corrosion resistance, for the need for The plastic parts of the coating are subjected to special treatment before painting, thereby improving the adhesion of the coating film and the plastic surface.

What is the general application of the chrome-free passivation process? What is the role of chromium-free passivation agent? What is the difference between a chromium-free passivation process and a WGD chrome-free passivation agent?

In order to protect the environment of human survival, China's use of chromate and waste emissions to make increasingly stringent restrictions in the field of metal surface treatment of chromate will eventually be prohibited to use has become an inevitable trend. To this end, the development of new environmentally free chromium-free passivation technology to replace chromate passivation is engaged in metal surface treatment technology, an important task of science and technology workers.

When the treated agent containing Cr6 + is in contact with the metal surface, part of Cr6 + is reduced and forms a dense "coating" of Cr3 + hydrated oxide on the metal surface. This layer of film can be a large extent to block the environment of water, oxygen, salt and other corrosive substances into the metal surface. Once the film is damaged, Cr6 +, which is not reduced in the film, will automatically oxidize the new exposed metal surface, and the Cr3 + hydrated oxide formed by the reduction will form a new "film" to repair the damaged site. Therefore, due to the mutual cooperation of these two functions, making the chromium-containing film has good corrosion resistance.

In the process of finding alternatives to chromates, there are more molybdates, tungstates, silicates, titanium salts, zirconium-containing solutions, cobalt-containing solutions, rare earth metal salt solutions, Cr3 + solutions, phosphoric acid Salt passivation and other inorganic salts passivation, but also the use of tannic acid, phytic acid, acrylic, epoxy resin, organic silane and other organic passivation. However, the study found that there is no single inorganic or organic matter with chromate similar to the film-forming and self-repair ability.

The industry has been in the development of harmless, and environmentally friendly equipment and pharmaceuticals, after years of research found that chromium-free passivation treatment process development, must take the complex technology line, that is, by a variety of excellent single function of organic, Inorganic composite form, in the film and self-repair ability to play the ultimate chromium-free passivation agent.

Chromium-free passivation treatment consists of two types of forming film and corrosion inhibitor. Improve the compactness of the forming film at the same time, play a self-repair effect of the corrosion inhibitor, according to the different characteristics of different corrosion inhibitors, making the overall corrosion inhibition effect to or close to the level of Cr6 +