Basic types of corrosion of industrial aluminum profiles and aluminum alloys

December 26, 2024

Generally speaking, the fundamental examples of corrosion in Industrial Aluminum Profiles and aluminum alloys include point corrosion, galvanic corrosion, intergranular corrosion, stress corrosion, peel corrosion, fatigue corrosion, filamentous corrosion, etc. Here, we will only introduce the common corrosion phenomena in the production and utilization of industrial aluminum profiles through the deployment of equipment for aluminum setting.

Point decay, also known as hole decay, is a highly localized form of decay on metals that produces needle like, dot like, and hole like structures. Point decay is a peculiar phenomenon of anodic reaction, which is a self catalytic process. Aluminum undergoes slight corrosion in the atmosphere, freshwater, and neutral aqueous solutions, and can even cause perforation in severe cases. However, the ultimate goal of corrosion perforation is to prevent growth, and the amount of corrosion is limited to a certain limit. Point decay is related to the medium alloy at the extreme level, such as chloride ions, fluoride ions, etc. There must also be substances that promote cathodic reactions, such as dissolved oxygen and copper ions in aqueous solutions. From the perspective of industrial aluminum profiles and aluminum alloys, high-purity aluminum profiles are usually difficult to produce pitting corrosion, with copper containing aluminum alloys showing the most significant pitting corrosion.

Galvanic corrosion is also a characteristic form of corrosion of aluminum. Aluminum has a very negative natural potential, and when it fights against other metals, it always remains at the anode, accelerating its corrosion. Galvanic corrosion, also known as bimetallic corrosion, is determined by the relative position of the potential sequence between two metals. The larger their potential difference, the more severe the galvanic corrosion, and almost all aluminum alloys cannot stop the galvanic corrosion.

Vulnerabilities and corruption exist in the appearance of industrial aluminum profiles, either on their own or in combination with other materials. Due to the differential effect of inflatable batteries, the corrosion within the loopholes accelerates, while there is no impact outside the loopholes. Vulnerability corrosion is not closely related to alloy examples, even highly corrosion-resistant alloys can produce vulnerability corrosion. In recent years, there has been a deeper study on the mechanism of dealing with vulnerability corruption, and the acidity at the top of the vulnerability is the driving force behind corruption. Decay under sediment is a form of vulnerability decay.

Intergranular corrosion, pure aluminum is not prone to intergranular corrosion, and the cause of intergranular corrosion is related to improper heat treatment punishment. Alloying elements or intermetallic compounds precipitate along the grain boundaries, and the anode of the relative pair of grains forms a corrosion battery, causing accelerated intergranular corrosion.

Filamentous decay, also known as filamentous decay, is a type of subsurface decay that grows in the form of worms under the film. This type of film can cause damage to the paint film or other layers, but it usually does not occur under the anodic oxide film. Filamentous decay was first invented under the layer of aircraft, and this year it has been continuously reported in Europe that it also occurs under the spray coating of aluminum profiles in the construction industry. The relationship between filamentous corrosion and alloy identity is related to the pre-treatment punishment and situational factors of Jiangyin aluminum profile manufacturers before coating, including humidity, temperature, chloride, etc.

Author:

Mr. zhichengaluminumindustry

E-mail:

zcd.aluminum@gmail.com

Phone/WhatsApp:

+852 64053048