Combining screws with the ability to resist oxidation in the atmosphere --- not rust, but also has the ability to resist acid, alkali, salt medium, corrosion resistance - corrosion resistance. But its corrosion-resistant steel has its own chemical composition of size, increasing mutual status, utilization and environmental media types and changing conditions. Because 304 steel pipe has good corrosion resistance in dry and clean atmosphere, but it will be moved to the beach area with a lot of salt and fog, and will rust quickly; while 316 steel pipe has good performance. Therefore, no combination screw of any kind has the ability to corrode, rust in any environment.
The combination screw is a thin layer of the surface of the formation and the stability of the fine solid chromium-rich oxide film (protective film), in order to prevent the penetration of oxygen atoms, oxidation, to obtain the ability to resist corrosion. Once, for some reason, this film is constantly destroyed, the atoms of air or liquid oxygen will continue to penetrate or the atoms of the metallic iron will remain with the iron oxide formed loosely from it, and the metallic surface will be subject to constant corrosion. Many of these forms of membrane failure on surfaces, seen in everyday life, are as follows:
A combination screw containing attachments such as metal element dust or heterogeneous metal particles is deposited on the surface of the combination screw between humid air, condensed water and adhesion of the combination screw, and the two are connected into a micro-battery, which triggers an electrochemical reaction, and the protective film is The damage is called electrochemical corrosion.
2 Combination screw surface organic juice (such as vegetables, soup, sputum), in the presence of oxygen in the water, the formation of organic acid adhesion, organic acid is long on the surface of metal corrosion.
Materials containing acid, alkali, salt 3. Combination screw surface adhesion (such as alkaline water, lime water splash wall decoration), causing local corrosion.
4. In air pollution (such as atmosphere containing a large amount of hydrogen sulfide, carbon dioxide, nitrogen oxides), it meets the chemical corrosion caused by condensed water, the formation of sulfuric acid, nitric acid, acetic acid, and liquid.
The above-mentioned conditions can lead to the destruction of the protective film which causes the corrosion surface of the combination screw. Therefore, in order to ensure that the metal surface is permanently bright and cannot be corroded, we recommend:
1. It should be cleaned regularly, the surface of the combination screw should be decorated, the attachments should be removed, and the correction caused by external factors should be eliminated.
2. Use 316 combination screws in coastal areas, and the 316 material can resist seawater corrosion.
3. Some chemical components of the combination screws in the market cannot meet the corresponding national standards and cannot meet the 304 material requirements. It can also cause rust, which requires users to carefully choose a reputable manufacturer.
