Aluminum coil products are widely used in automotive, construction and other industries, aluminum materials in the air is very unstable, easy to generate with the naked eye is also difficult to identify the oxide film. As the different processing methods of aluminum parts, such as casting molding or by the direct shear sheet is cut, or machining precision molding, or by different processes and after heat treatment or welding, the workpiece surface will be presented different states, different levels of dirt or traces, for which the pre-treatment process must be based on the actual situation of the work piece surface to choose the pre-treatment process.
Aluminum tube coil fine processing parts in the pre-treatment process need to pay attention to the problem: Although the surface of the fine processing of the original oxide film was born, easier to remove, but oily heavy, especially around and within the hole, such artifacts must first Organic solvent cleaning, if not directly alkaline cleaning is not only difficult to remove oily net, and fine processing can not withstand the strong alkali corrosion for a long time, the result will affect the surface roughness and tolerance of the workpiece, and ultimately may become waste.
Aluminum coil sheet pretreatment process need to be aware that not all surfaces are cast machined machined parts, left unprocessed surface leaving the casting process is too thick oxide layer formed, and some also sand, this time should be used first machining or sandblasting method to remove the original part of the original oxide film, or caustic after the re-processing, the only way to both net raw parts of raw oxide layer, but also to avoid the size of the machined parts to change the size.