When brown rust spots (spots) appeared on the surface of perforated stainless steel pipes, people were surprised: "Stainless steel does not rust, and rust is not stainless steel. It may be that steel has appeared. The problem. In fact, this is a one-sided misconception about the lack of understanding of stainless steel.

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Stainless steel speaker nets, perforated nets and other metal processing products will rust under certain conditions. Stainless steel has the ability to resist atmospheric oxidation—that is, it is not rusty, and it also has the ability to corrode in media containing acid, alkali, and salt—that is, corrosion resistance. However, the size of its corrosion resistance varies with the chemical composition of the steel itself, the state of mutual addition, the use conditions and the type of environmental media. Such as 304 steel pipe, in a dry and clean atmosphere, has absolutely excellent anti-corrosion ability, but when it is moved to the seaside area, it will quickly rust in the sea fog containing a lot of salt; while 316 steel pipe has performance good. Therefore, it is not any kind of stainless steel, which is corrosion-resistant and does not rust in any environment. Stainless steel is an extremely thin, strong, dense and stable chromium-rich oxide film (protective film) formed on its surface to prevent oxygen atoms from continuing to penetrate and continue to oxidize, thereby obtaining the ability to resist corrosion. Once for some reason, this film is continuously destroyed, oxygen atoms in the air or liquid will continue to infiltrate or iron atoms in the metal will continue to separate out, forming loose iron oxide, and the metal surface will continue to be rusted. There are many forms of damage to this surface film.

There are several common ones in daily life: 1. The surface of stainless steel has accumulated dust containing other metal elements or attachments of foreign metal particles. In humid air, the condensation water between attachments and stainless steel, Connecting the two into a micro-battery triggered an electrochemical reaction and damaged the protective film, which is called electrochemical corrosion. 2. The surface of stainless steel adheres to organic juice (such as melon, vegetable, noodle soup, sputum, etc.), which forms organic acid in the presence of water and oxygen, and the organic acid will corrode the metal surface for a long time. 3. The surface of stainless steel adheres to containing acids, alkalis, and salt substances (such as alkaline water and lime water splashing on the decoration walls), causing local corrosion. 4. In polluted air (such as the atmosphere containing a large amount of sulfide, carbon oxide, and nitrogen oxide), it will form sulfuric acid, nitric acid, and acetic acid liquid spots when encountering condensed water, causing chemical corrosion. The above conditions can cause damage to the protective film on the stainless steel surface and cause rust.

Therefore, in order to ensure that the metal surface is permanently bright and not rusted, we recommend: 1. The decorative stainless steel surface must be cleaned and scrubbed frequently to remove attachments and eliminate external factors that cause modification. 2. 316 stainless steel should be used in coastal areas, which can resist seawater corrosion. 3. The chemical composition of some stainless steel pipes on the market cannot meet the corresponding national standards and cannot meet the material requirements of 304. Therefore, rust will also be caused, which requires users to carefully choose products from reputable manufacturers.