Reasons for stainless steel angle bar rust

The stainless steel angle bar 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 gaining corrosion resistance. Once for some reason, the film is continuously destroyed, the oxygen atoms in the air or liquid will continue to infiltrate or the iron atoms in the metal will continue to separate out, forming loose iron oxide, and the metal surface will also be continuously affected. Rust. There are many forms of damage to the surface film, and the following are more common in daily life:    


  1. The surface of the stainless steel angle bar accumulates dust containing other metal elements or attachments of foreign metal particles, in humid air , The condensed water between the attachment and the stainless steel angle steel connects the two to form a micro battery, which triggers an electrochemical reaction and damages the protective film, which is called electrochemical corrosion.


  2. The surface of the stainless steel angle bar adheres to the organic juice (such as melon, vegetable, noodle soup, etc.), which forms organic acid in the presence of water and oxygen, and forms the organic acid to corrode the metal surface for a long time.   


  3. The surface of the stainless steel angle bar contains acid, alkali, and salt substances (such as alkali water and lime water spraying on the decoration wall) causing local corrosion.  


  4. In polluted air (atmosphere containing a lot of sulfides, oxides, and hydrogen oxides), contact with condensed water will form sulfuric acid, nitric acid, and acetic acid spots, causing chemical corrosion.  


The above conditions can cause damage to the protective film on the surface of the stainless steel angle steel and cause corrosion.