Effect of anodic oxidation on the strength of aluminum

Anodizing is a common surface treatment process, mainly used to improve the corrosion resistance and wear resistance of aluminum. By forming a dense oxide film on the surface of the aluminum, anodizing can effectively protect the aluminum from environmental erosion. However, does the anodizing process affect the strength of the aluminum?

​1. Factors affecting the strength of aluminum by anodizing

The thickness and structure of the oxide film: the thickness and structure of the anodic oxide film will directly affect the strength of the aluminum. The thickness of oxide film is related to current density, voltage and other factors. The higher the current density and voltage, the faster the film formation speed, but it will also cause the temperature of the oxidation liquid to rise, thus affecting the quality of the film. If the oxide film is too thick or the structure is loose, it may lead to a decrease in the strength of the aluminum.

​The composition and heat treatment state of aluminum: The composition and heat treatment state of aluminum have a great impact on the appearance and performance of anodic oxide film. When the aluminum alloy profiles with high copper or silicon content are anodized, the film layer may be loose and porous, which affects the strength of the aluminum.

​2. The specific impact of anodizing on the strength of aluminum

Improve surface hardness and wear resistance: Anodizing can increase the surface hardness and wear resistance of aluminum parts. This means that anodizing can improve the strength of aluminum to a certain extent, especially in the surface area.

​May cause strength reduction: If the thickness of the anodized film is not uniform or the structure is loose, the strength of the aluminum may be reduced. In addition, if the aluminum surface has serious scratches, tissue defects and inclusions, it will also affect the quality of the oxide film, thus affecting the strength of the aluminum.

​3. How to control the influence of anodizing on the strength of aluminum

Select the appropriate oxidation process parameters: current density, voltage, oxidation time and other factors will affect the quality of the oxide film. Therefore, selecting the appropriate oxidation process parameters can effectively control the thickness and structure of the oxide film, so as to ensure the strength of the aluminum.

​Choosing the right aluminum composition and heat treatment state: Choosing the right aluminum composition and heat treatment state can ensure the quality of the anodic oxide film, thus ensuring the strength of the aluminum.

​Step 4 Summarize

The influence of anodizing on the strength of aluminum depends on many factors, including the thickness and structure of the oxide film, the composition of aluminum and the heat treatment state. Although anodizing can improve the surface hardness and wear resistance of aluminum, if the thickness of the oxide film is not uniform or the structure is loose, it may lead to a decrease in the strength of aluminum. Therefore, when anodizing, it is necessary to select the appropriate oxidation process parameters and aluminum composition to ensure the quality of the oxide film, so as to ensure the strength of the aluminum.