Here are the steps involved in the anodizing process for aluminum plates:

1. Cleaning: The aluminum plate is cleaned thoroughly to remove any dirt, grease, or other impurities that may be present on the surface. This is typically done with a degreaser or other cleaning solution.
2. Pre-treatment: The aluminum plate is then treated to prepare the surface for anodizing. This may involve a chemical etch or mechanical surface preparation to remove any remaining surface contaminants and create a uniform surface.
3. Anodizing: The aluminum plate is immersed in an electrolyte solution, typically sulfuric acid, and an electric current is applied to the surface. This causes the aluminum to react with the acid, forming an oxide layer on the surface of the metal. The thickness of the oxide layer can be controlled by adjusting the voltage and time of the anodizing process.
4. Coloring: If desired, the anodized aluminum plate can be dyed to add color to the surface. This is done by immersing the plate in a dye solution, which is absorbed into the pores of the oxide layer. Different colors can be achieved by using different dyes.
5. Sealing: Finally, the anodized aluminum plate is sealed to improve the durability and corrosion resistance of the surface. This is typically done by immersing the plate in a hot water or chemical bath that causes the pores in the oxide layer to close up, creating a more uniform surface.

Overall, the anodizing process creates a hard, durable surface that is resistant to corrosion and wear. Anodized aluminum plate is widely used in a variety of applications where durability and performance are essential.