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Because of the excellent characteristics, aluminum sheet can be seen everywhere in daily life, it has a layer of oxide film on the surface, which makes the use period last longer. But in the use process, you may still found some dark spots attached on the surface of the aluminum sheet! What is the reason? How can we prevent from it? Don’t worry, with more than 20 years manufacturing experience, HAOMEI Aluminum can help you solve this problem.

If there are dark spots on the surface of aluminum sheet, the problem may usually occur when painting silver and spray on the aluminum sheet. First of all, it may occur in the spray, if the mouth of the seal is not strict, so there are some organic inclusion in the spray and is sprayed on the surface of the aluminum sheet. Moreover, some organic gases will also cause corrosion of the surface of the aluminum sheet and formation of dark spots on the surface. While the common gas course effects and corrosion of aluminum sheet plate is mostly sulfur-containing gases. Secondly, when the aluminum sheet is in the plating, if a part of the process is fail, it will also lead to the dark spots on the surface, if the environment is closed, it may be because the plating conditions or process problem, which led to the emergence of dark spots. Therefore, when the aluminum sheet is silver-plated, in order to prevent the impact of sulfur elements, after the parts after silver plating, timely store the aluminum sheet and keep sealed, and then placed in dry environment, it can be a good way to prevent this problem effectively.

[/url][url=http://aluminum-hot-rolled-plate.com/]Aluminum plate is divided into pure aluminum plate, alloy aluminum plate, thin aluminum plate, medium and thick aluminum plate pattern aluminum plate. The aluminium plate used in the building includes many kinds of materials, such as single layer aluminum plate, composite aluminium plate, etc., and usually refers to a single layer aluminum plate, which is mostly used in architectural decoration project. In recent years, the single deck aluminum plate used in the aluminum curtain wall is more common. Shenzhen aluminum supplier analyzes the causes of black spot on aluminium plate surface.




First is the aluminum plate material, the aluminum plate manufacturer produces the aluminum plate the upper cover is by the 0.5mm thick LF21 aluminum plate processing. The aluminum sheet of this model has a variety of materials, similar shapes and parts of the same process, while similar parts of the same type of processing did not occur at the same time. And this is not the fault caused by the defect of the raw material. It is in the process, silver plated cover roughly the process route is: machine parts - Pretreatment - zinc - zinc - plating copper plating - paint - dipping 823 - storage.

Cause analysis of black spot on aluminum plate \"

On the aluminum plating process, first of all, there may be a production process of electroplating has changed, which led to the failure. But the investigation found that the production conditions did not change any situation, the same period of processing similar parts did not appear such failures. Therefore, the factors that influence the change of electroplating conditions have been eliminated. According to the previous production experience, the most common reason for the discoloration of silver plate is the effect of sulfur on the silver coating.

In the past, silver plated parts were not packed in time and sealed for preservation. They were left in the plating room for a long time, resulting in yellowing of the silver coating. However, after the failure of the silver plated parts are packaged in a timely manner and placed in a dry container to save, it can be seen that this is not affected by the factory air atmosphere. In the painting process, it is found that the upper cover of the paint processing, there has been a batch of repair records. The most important reason is that the gap is not blocked so that the paint mist enters and adheres to the surface of the silver plating layer and cannot be removed. To prevent the occurrence of such failures, it is suggested that the 3M tapes be used to seal the gap so as to prevent the paint mist from entering.

Through this method of elimination, the root of the problem has been found, and measures should be taken to prevent the recurrence of the hidden trouble, so that the surface of the aluminum plate is bright and new, and the factory rate will be greatly improved.