Polishing refers to the use of mechanical, chemical or electrochemical effects, so that the surface of the aluminum profile roughness reduced, in order to obtain a bright, flat surface of the processing method. It is the modification of the surface of aluminum profile using polishing tools and abrasive particles or other polishing media.

Mechanical polishing is the use of polished wax polishing wheel swashes the surface of the aluminum alloy shell. The aim is to reduce the roughness of the aluminum alloy surface, make the surface smooth, obtain a bright or mirror effect, can effectively repair aluminum alloy surface scratches and scratches.

Chemical polishing is the chemical immersion of aluminum under certain conditions. In this immersion process, the metal surface is eroded and flattened by the solution, thus obtaining a brighter surface. The advantages of chemical polishing are: no need to add power supply, can handle the shape of more complex aluminum, high production efficiency, but chemical polishing surface quality, generally slightly lower than chemical polishing, solution adjustment and regeneration is also more difficult, often in the polishing process will be extracted nitrogen oxide and other harmful gases.

Electrochemical polishing is also known as electro polishing. Electrolytic polishing is to be thrown aluminum as an anode, insoluble metal as a cathode, the poles are immersed in the electrolytic cell at the same time, through direct current and produce selective anode dissolution, so that the surface brightness of aluminum profile increases, to achieve the mirror effect. However, electrolytic polishing can not remove non-metallic inclusions of aluminum profiles, nor can it remove or disguise surface defects such as scratches and deep hemp points on metal surfaces.