Project Description
The basic corrosion types of industrial aluminium profiles are point corrosion, electrode electric corrosion, crevice corrosion, intergranular corrosion, filamentary corrosion, etc. Here’s a quick overview of the types of corrosion.
1. Point Corrosion
Point corrosion is also known as pore etching, which is a very localized corrosion form of a needle, dot, and hole in the metal. Aluminium in the atmosphere, water, or corrosion occurs and neutral aqueous solution, serious still can cause perforation, but may eventually stop developing corrosion hole, corrosion amount keep a limit value. Point corrosion is a unique form of anodic reaction and is an autocatalytic process.
2. Galvanic Corrosion
Electro electric corrosion is also a characteristic corrosion form of aluminium. The natural potential of aluminium is very negative. When aluminium is in contact with other metals, aluminium is always in the anode to accelerate its corrosion. Electro electric corrosion is also known as bimetallic corrosion. The severity of corrosion is determined by the relative position of two metal potentials.
3. Crevice Corrosion
Crevice corrosion is caused by the difference of inflatable cell function, which causes the corrosion acceleration in the gap, and the gap is not affected. Crevice corrosion is not associated with alloy type, even the very corrosion resistant aluminium alloy can cause crevice corrosion. In recent years, the mechanism of crevice corrosion has been further studied, and the acidic environment at the top of the gap is the driving force of corrosion.
4. Intergranular Corrosion
Intergranular corrosion is pure aluminium is not prosperous intergranular corrosion, intergranular corrosion reason has something to do with the improper heat treatment, alloying elements or intermetallic compound along the grain boundary precipitates out, relative to the grain as a corrosion cell anode, intergranular corrosion caused by acceleration.
5. Filamentous Corrosion
Filiform corrosion is a film of corrosion, a worm-like development under the film, the film can make the paint film, also can make the other layer, generally does not occur under the anodic oxidation film, industrial aluminium processing factory to provide the reference.