Reasons for rusting of stainless steel compensators

Reasons for rusting of stainless steel compensators
Stainless steel has the ability to resist atmospheric oxidation - that is, it will rust - and also has the ability to be in media containing acids, alkalis and salts - that is, to resist corrosion. But the size of its ability varies with the chemical composition of its steel itself, plus mutual state, working conditions and the type of surrounding media. Like 304 steel pipe, in the air of dry cleaning, there is absolutely good resistance to discoloration, but moved to the sea, in the sea spray containing a lot of salt, will soon rust; 316 steel pipe is good performance. Therefore, there is not any kind of stainless steel will not rust in any environment.
 
Stainless steel relies on a thin, dense, stable chromium-rich oxide film (protective film) formed on its surface to prevent oxygen atoms from continuing to penetrate and oxidize, thus gaining the ability to resist corrosion. Once the film is continuously damaged for some reason, oxygen atoms in the air or liquid will continue to infiltrate or iron atoms in the metal will continue to precipitate, forming loose iron oxide, and the metal surface will continue to rust. There are many forms of damage to this surface film, the most common in daily life are the following:
 
1, stainless steel surface accumulation of dust containing other metal elements or adhesion of foreign metal particles. In humid air, the condensation between the attachment and stainless steel connects the two into a miniature battery, triggering an electrochemical reaction, the protective film is destroyed, which is electrochemical corrosion.
 
2, attached to the stainless steel surface of the juice (such as vegetables, noodle soup, spit, etc.), in the presence of water and oxygen, will form acid, acid will corrode the metal surface for a long time.
 
3, stainless steel surface attached to acid, alkali, salt substances (such as decoration with alkaline water, lime water splashed on the wall), resulting in local corrosion.
 
4, in the polluted air (such as containing a large number of sulfides, carbon oxides, nitrogen oxides in the atmosphere), in the presence of condensation water, will form sulfuric acid, nitric acid, acetic acid liquid point, causing chemical corrosion.