ã€China Aluminum Industry Network】If the metal cleaning agent sold in the city can be applied to the cleaning of aluminum parts, the pH value range must first be known. If the pH value is too high, it cannot be used. Otherwise, the surface of the aluminum parts may be subject to corrosion. Because these metal cleaners are usually free of aluminum corrosion inhibitor components, they do not act to prevent the etching reaction, so that when the oil stain on the metal surface is washed away faster, the surface of the aluminum workpiece is also stained. In order to avoid the occurrence of the above phenomenon, first of all to do a good job of pretreatment, that is, prior to the full use of organic solvents degreasing, so that the surface reaches a substantially uniform degree of cleanliness, before using this metal cleaning agent.