Ways to prevent corrosion of coated aluminium strip during storage and transportation

As a aluminum strip manufacturer, Haomei Aluminum found that water the main culprit of corrosion of coated aluminium strip during storage and transportation, whether annealing state or hard state, as long as water or affected with damp, any kind of packaging way will suffer corrosion. The water corrosion has a characteristic, namely in the surface of aluminium strip, there is a white watermark corrosion boundaries, area under the influence of water with large area of corrosion state and no obvious directivity. There is no obvious watermark corrosion boundary in the complex form of damp corrosion.

Color Coated Aluminum Strip Coil manufacturers have found that hard aluminum bands actually corrode when exposed to water, but at a much slower rate than annealed aluminum bands due to the protection of the oil film. We have tried it before: a roll of annealed aluminium strip is packed with water, and a day later, two sides of the strip are corroded by obvious water mark. However, a roll of hard aluminum strip was immersed in water and exposed for 6 months. It was found that the outermost layer did not corrode, but there was water corrosion in the roll. There is a certain amount of water in the air. When the cold aluminum strip is transported or stored in the high temperature area, the water in the air will condense on the surface of the aluminum strip. Water condensed on the surface of cold aluminium strip, the relative humidity (RH %) and aluminum strip with the surrounding air temperature are different when a case with the water, because the water amount is larger, the other aluminium strip will be affected with damp due to water evaporation.

Haomei Aluminum found that water on the Perfect Cutting Edge strip surface will be as a result of the transverse crack interaction of inhaling aluminum belt, forming invisible to the naked eye 10 nm ~ 1 microns thin water film, the thickness of water film is metal corrosion is most serious and fastest area.