Aluminum alloy often has different colors different colors on the same aluminum block after anodiz

I also raised this question some time ago, and now that this problem has been solved, the countermeasures can reduce the temperature, concentration, and voltage, and you can refer to what I asked others.

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Resolved. How to solve the inconsistency between the upper and lower shades of anodizing dyeing?

Dyeing out the same hanging goods is deep above and shallow below, even a cargo is like this, the top is deep, the bottom is shallow, how to solve it, I hope the master will give advice.

Can't sleep squinting and smiling 5-05 12:00

If you have measured the gloss of the two ends, you will find that the gloss of the two ends is not the same, I also encountered the same problem a few days ago, the same product up and down and left and right lab values are a large number of different, if your product has the process of chemical throwing, you can first solve it from the chemical throwing potion, and the chemical throwing potion will cause the temperature to be different if it is not pumped.

Other answers. It may be that the outlet of the cooling circulation pump pipeline is too close to the workpiece, and the outlet of the liquid medicine should not be directly facing the workpiece. It is best to hit one end of the groove evenly to the other end. In addition, the pole spacing between the cathode and anode should be more than 25 cm.

When this phenomenon occurs on the same workpiece, there are several reasons:

1. Pre-treatment polishing, the proportion of the potion is uneven, it is necessary to blow the air to make the proportion of the potion and the temperature uniform, if it is a three-acid polishing and it is related to the technique, if it is a large piece, it must be preheated first, otherwise it will also affect the subsequent uneven color.

2. Conductivity.

When the hanging position of the hanging tooth conductivity is not good, the structure of the surviving film will be different, the film layer is regular where the conductivity is good, and the film layer will be irregular when the conductivity is not very good, which is an abnormal living film, so it will also cause the phenomenon of different colors.

3. After oxidation, the neutralization is not in place or the neutralization concentration is insufficient, the concentration of the dyeing solution in the dyeing is high, there is no stirring equipment, and the pH is low.

<> normal anodizing is less than 20mu, it will be white, and after more than 25mu, it will turn gray and dark green. Anodizing, electrochemical oxidation of metals or alloys. The process of forming an oxide film on aluminum products due to the action of impressed current under the corresponding electrolyte and specific process conditions.

Anodizing usually refers to sulfuric acid anodizing, if not specifically specified. In order to overcome the defects of aluminum alloy surface hardness, wear resistance, etc., expand the application range and prolong the service life, surface treatment technology has become an indispensable part of the use of aluminum alloy, and anodizing technology is currently the most widely used and most successful.

Why does aluminum anodizing have color transfer: the reasons are as follows: 1. Reasons for anodizing 1. Oxidation dyeing principle The anodic oxide film is composed of a large number of hexagonal unit cells perpendicular to the metal surface, each unit cell has a membrane hole in the center, and has a strong adsorption force, when the oxidized aluminum products are immersed in the dye solution, the dye molecules enter the membrane pores of the oxide film through diffusion, and at the same time form covalent bonds and ionic bonds that are difficult to separate with the oxide film.

This bonding is reversible and desorption occurs under certain conditions. Therefore, after dyeing, it must be sealed to fix the dye in the membrane pores, and the corrosion resistance and wear resistance of the oxide film must be increased. 2. The influence of anodizing process on dyeing In the whole process of oxidation dyeing, poor dyeing caused by oxidation process is relatively common.

The uniform film thickness and pores of the oxide film are the premise and basis for obtaining a uniform color during dyeing, in order to obtain a uniform oxide film, it is important to ensure sufficient circulation, cooling capacity, and good conductivity, in addition to the stability of the oxidation process.

White. The principle of aluminum anodizing is essentially the principle of water electrolysis. When an electric current is passed, the following reaction will take place: On the cathode, hydrogen gas is released in the following reaction: two hydrogen ions are combined with two electrons.

On the anode, 4 hydroxide ions are combined with 4 electrons, and the precipitated oxygen is not only the oxygen in the molecular state, but also the atomic oxygen (O), as well as the negatively charged oxygen ions, which are usually represented as molecular oxygen in the reaction.

After anodizing, the surface of aluminum can form an oxide film from a few microns to hundreds of microns. Compared with the natural oxide film of aluminum alloy, its corrosion resistance, wear resistance and decoration have been significantly improved and improved.

The positive color of the slag of aluminum alloy secondary anodizing can vary according to the process and treatment method. Generally speaking, aluminum alloys can take on a variety of colors after secondary anodizing, including but not limited to the following:

Natural silver: At this time, a colorless or faint oxide film is formed on the surface of the aluminum alloy, showing a silvery-white natural luster.

Black: After special treatment, the surface oxide film of the aluminum alloy can appear black beam, creating a high contrast and unique aesthetic effect.

Gold or Brown: By adjusting the process parameters and adding the appropriate dye, the oxide film on the surface of the aluminum alloy can be made to appear golden or brown, creating a metallic texture and a warm touch.

Color: In the oxidation process, through electrolytic coloring or dyeing of the oxide film, the surface of the aluminum alloy can be made to present a variety of bright color effects, such as red, blue, green, etc., to increase the aesthetics and decoration.

It should be noted that the specific color effect will also be affected by the composition of the aluminum alloy, the treatment method, the surface quality and environmental factors. Therefore, in practical applications, the appropriate process and post-processing method can be selected according to the needs to obtain the desired color effect.

Aluminum oxidizes and turns white after ordinary anodizing, and can also be further passivated and blackened.

Alumina is a white amorphous powder that comes in several variants, the most well-known of which are alo and alo. The corundum that exists in nature belongs to an ALO, its hardness is second only to diamond, high melting point, acid and alkali resistance, and is often used to make some bearings, abrasives and refractories.

Such as corundum crucible, can withstand high temperatures of 1800. ALO comes in a variety of colors due to the presence of different impurities. For example, those containing trace amounts of Cr(III) are red in color and are called rubies; Those containing Fe(II), Fe(III) or Ti(IV) are called sapphires.

The chemical symbol is AL, atomic number: 13. The content of aluminum in the earth's crust is second only to oxygen and silicon, ranking third, and it is the most abundant metal element in the earth's crust, and its reserves are the second in the metal. Among the metal varieties, it is the second largest group of metals after steel.

Hello, I'm glad to answer that it is caused by the action of grease. If grease is mixed into the anodizing solution, the oil film will be reflected due to the adsorption of the oxide film, and the color will be rainbow.

Summary. 1. The alkali washing of the workpiece is not thorough enough.

2. The temperature of the staining solution is too low.

3. There is oil stain on the surface of the dyeing solution.

4. The near-working products of the film layer have not been cleaned.

5. The oxide film is polluted.

6. After oxidation, the water washing is not thorough enough and is not cleaned.

7. The current density is too large when the aluminum profile is oxidized.

8. The temperature of the anodizing solution is too low, and the current density is too small.

9. The temperature of the anodizing solution of the aluminum profile is too high.

Aluminum plates are flower after anodizing and dyeing, what is the reason?

1. The alkali washing of the workpiece is not thorough enough. 2. The temperature of the staining solution is too low. 3. There is oil stain on the surface of the dyeing solution.

4. The near-working products of the film layer have not been cleaned. 5. The oxide film is polluted. 6. After oxidation, the water washing is not thorough enough and is not cleaned.

7. The current density is too large when the aluminum profile is oxidized. 8. The temperature of the anodizing solution is too low, and the current density is too small. 9. The temperature of the anodizing solution of the aluminum profile is too high.

That's it, what is the main reason.

It may be the cause of the current temperature being too high or too low during oxidation.