How to do a good job to improve the quality of aluminium sheet products pretreatment work

Aluminium sheet products are widely used in the automotive, construction and other industries, improving the quality of aluminium products is fundamental to the survival of enterprises, aluminium materials in the air is extremely unstable, easy to generate with the naked eye also difficult to identify the oxide film. Due to the different processing methods of aluminium parts, such as casting, or shearing directly from the extended plate, or mechanical fine processing, or by different processes after forming and heat treatment or welding, the surface of the workpiece will show different states, different degrees of dirt or traces, for this reason in the pre-treatment process must be based on the actual situation of the surface of the workpiece to choose the pre-treatment process method.

It should be noted that not all the surfaces of the castings are machined, and the unmachined surface has a thick oxide layer formed during the casting process, and some of them have a sand layer, which should be machined or sandblasted to remove the original oxide film of this part, or processed after alkali washing, which is the only way to remove the original oxide layer of the unmachined part, and avoid machining. Part tolerance size change.

Fine processing parts in the pre-treatment process need to pay attention to the problem: fine processing parts although the surface of the natural oxide film before the first generation, easier to remove, but greasy heavy, especially in and around the eye, such workpiece must first be cleaned by organic solvents, if the direct use of alkali washing not only greasy heavy difficult to remove, and fine processing surface can not withstand a long time of strong alkali corrosion, the result will also affect the surface roughness of the workpiece and tolerance The result will also affect the surface roughness and tolerances of the workpiece, which may eventually become scrap.