There are natural oxide films and other pollutants on the original surface of aluminum materials, and even defects such as slight bumps and scratches. In order to improve the decorative effect of aluminum materials and the subsequent main process of aluminum surface treatment (anodizing processing or chemical conversion processing, etc.), the surface pretreatment of aluminum materials must be carried out first.
The process of pretreating aluminum surface with compound solution or solvent is called chemical pretreatment of aluminum. It is the most commonly used and generally the most economical aluminum surface pretreatment process. Grease, contaminants and natural oxide film, etc., to obtain a wet, uniform clean surface of aluminum.