What Are the Corrosion Forms of Industrial Aluminum Aluminum Profiles? -WJW Aluminum Supplier Aluminum

Metal corrosion exists in various areas of the national economy. With the development of economic construction and the development of science and technology, the harm of corrosion is becoming more and more serious, and restrictions on the development of the national economy are becoming more and more prominent.

As an active metal, industrial aluminum can easily generate alumina for oxygen reactions in the air, and form a solid film on the aluminum surface, which can completely separate the outside oxygen and corrosion. However, this membrane interacts with many acidic or alkaline substances. Once dissolved, it will not be corroded. Therefore, mastering the corrosion of industrial aluminum can better avoid aluminum corrosion.

one

Point corrosion

Point corrosion, also known as corrosion, is a very local form of corrosion, producing needles, dot -shaped and pore shapes on metals. Point corrosion is a unique form of anode reactions, a self -catalytic process. Aluminum corrosion occurs in atmospheric, fresh water or neutral aquatic solution, which may also cause perforation, but the corrosion can eventually stop developing, and the amount of corrosion will remain in One limit. The limit of point corrosion is related to medium alloys such as chloride ions and fluorine ions. There must also be substances that promote cathode reactions, such as dissolved oxygen and copper ions in the aqueous solution. From the perspective of industrial aluminum profiles, the erosion of high -pure aluminum profiles is generally difficult to occur, while the etching of copper -containing aluminum alloy is the most obvious.

two

Occasion

Electrolytic corrosion is also a characteristic corrosion of aluminum. The natural potential of aluminum is very negative. When aluminum is in contact with other metals, aluminum is always accelerated in the anode. Electric corrosion, also known as dual metal corrosion, depends on the relative position of the two metal potential sequences. The larger the potential difference, the more severe the electrical corrosion, and the more all aluminum alloys cannot avoid the corrosion of the electric puppet.

three

Gap corrosion

There is a gap in the surface contact between the industrial aluminum profile itself or the surface of the aluminum and other materials. Due to the effects of different inflatable batteries, the internal corrosion of the gap accelerated, but the external gap was not affected. The gap corrosion has nothing to do with the type of alloy, and even a very corrosive alloy can produce gap corrosion. In recent years, people have conducted deeper research on the mechanism of sewing corrosion. The acidic environment on the top of the crack is the driving force for corrosion. The corrosion of submersible accumulation is a form of sewing corrosion.

Four

Crystal corrosion

Pure aluminum does not prosper the corrosion of the crystal, and the cause of corrosion of the crystal is related to the improper heat treatment. Metal elements or inter -metal intervertebral compounds are precipitated along the crystal boundary. Compared with grains, the corrosive battery is formed by anode, causing the corrosion of the crystal to accelerate.

five

Filamentous corrosion

Silk corrosion is a sub -membrane corrosion that develops under the form of worms under the membrane. This coating film can not only make the paint film, but also make other layers. Generally, it will not occur under anode oxide. Silk corrosion was initially discovered under the aircraft layer, and this year it was also reported under the aluminum -shaped spray film in the European construction industry. Silk corrosion is related to environmental factors such as the pre -processing of alloy composition, pre -treatment of coated aluminum profiles and environmental factors such as humidity, temperature, and chloride.