What are the advantages and disadvantages of cold spraying zinc paint?

3. 1, excellent anticorrosion performance and high construction efficiency;

Cold spraying zinc combines the long-term anticorrosion of hot metal anticorrosion processes (hot spraying zinc, hot spraying zinc, hot spraying aluminum, hot spraying zinc-aluminum alloy) and the convenient construction of ordinary coatings. The long anti-corrosion life of hot metal spraying is due to the fact that the content of zinc or aluminum in the metal plating (coating) layer is 95-97%, while the content of zinc in the dry film coating of cold spraying zinc process is above 96%, which ensures the same anti-corrosion performance and anti-corrosion life as that of hot metal treatment. At the same time, the physical properties of cold-sprayed zinc products are in the same liquid state as ordinary coatings, and the requirements for surface treatment of steel structures are the same as Sa2.5, while those of hot-sprayed zinc, hot-sprayed aluminum and hot-sprayed zinc-aluminum alloy are higher than Sa3, and the construction methods are the same as ordinary coatings, such as high-pressure spraying, brush coating, roller coating and electrostatic spraying. It is briefly summarized that cold spraying zinc is a one-component coating with high zinc content, and cold spraying zinc is a construction method using coatings.

3.2, the construction environment temperature requirements:

Compared with common coatings, the requirements for construction environment temperature are wider, ranging from 5℃ to 50℃ for common coatings and-5℃ to 50℃ for cold-sprayed zinc. If the Sutong Bridge is constructed on site, it is basically not affected by the environmental temperature (the lowest monthly temperature in this area is about -2℃), which provides favorable conditions for projects with tight construction progress.

3.3, environmental protection and energy saving:

Cold-sprayed zinc is constructed at room temperature, without high energy consumption, zinc fog, industrial waste and other harmful substances, which has no impact on the construction unit and the project site environment, and is more environmentally friendly and energy-saving.

Disadvantages of cold spraying zinc

1, lack of industry awareness:

Compared with the mature conventional anti-corrosion technology, cold-sprayed zinc has been widely used abroad for decades (since 1970s), and it has been recognized by Party A and construction units in various industries. However, it was not popularized until 2000 in China, and the awareness of various industries was not enough. However, cold spraying zinc has been well applied in bridges, electric power, railways, coal chemical industry, large municipal venues and other industries, and has gradually become a mature and reliable anti-corrosion technology to replace hot metal anti-corrosion technology.

2, misunderstanding of adhesion:

Most owners and design units are worried that the bonding force between cold sprayed zinc and steel surface is not enough, and think that hot metal anticorrosion technology is better than ordinary paint, and they lack in-depth understanding of the bonding principle between cold sprayed zinc and steel surface. First of all, the original adhesion of cold-sprayed zinc coating can reach the national 1 level, just like ordinary paint (supported by the test report of national authoritative organization and many engineering application examples). Secondly, with the passage of time, the physical and chemical reaction between cold sprayed zinc and steel surface becomes more and more intense.