After the surface of the aluminum profile is anodized, a protective film will be formed to block the air, so that the aluminum profile will not be oxidized. This is also one of the reasons why many customers choose to use aluminum profiles, because there is no need to paint and the maintenance cost is low. But sometimes the surface of the aluminum profile is blackened. What is the reason for this? Let me give you a detailed introduction.
There can be a number of reasons for the blackening of aluminum alloy surfaces, some of which are:
1. Oxidation: Aluminum is exposed to air and reacts with oxygen to form a layer of aluminum oxide on the surface. This oxide layer is usually transparent and protects the aluminum from further corrosion. However, if the oxide layer is disturbed or damaged, it exposes the underlying aluminum to air and can cause further oxidation, resulting in a dull or blackened appearance.
2. Chemical reaction: Exposure to certain chemicals or substances can cause discoloration or blackening of the aluminum alloy surface. For example, exposure to acids, alkaline solutions, or salts can cause a chemical reaction that can cause darkening.
3. Heat treatment: Aluminum alloys are often subjected to heat treatment procedures to increase their strength and hardness. However, if the temperature or time of heat treatment is not properly controlled, it will cause discoloration or blackening of the surface.
4. Pollution: The presence of pollutants on the surface of aluminum alloys, such as oil, grease or other impurities, will cause discoloration or blackening due to chemical reactions or surface interactions.
5. Anodizing: Anodizing is a surface treatment process that involves the electrochemical treatment of aluminum to form a layer of oxide on the surface. This oxide layer can be dyed or tinted to produce a variety of finishes, including black. However, if the anodizing process is not properly controlled or the dyes or colorants are of poor quality, it can result in an uneven finish or discoloration.
Post time: Jun-08-2023