When the surface of the stainless steel pipe appeared on the surface of the brown rust spots (points), people were surprised: "stainless steel is not rusty, rust is not stainless steel, it may be a problem with steel." In fact, this is a one -sided misunderstanding of lack of understanding of stainless steel. Stainless steel will also rust under certain conditions.
Stainless steel has the ability to resist atmospheric oxidation-that is, stainlessness, and it also has the ability to corrode in acid, alkali, and salt-that is, corrosion resistance. However, the size of its corrosion resistance is changed with its steel itself chemical composition, additional state, conditions and environmental medium types. For example, 304 steel pipes, in the dry and clean atmosphere, have absolute excellent rust resistance, but move it to the seaside area, in the sea fog containing a large amount of salt, it will soon rust; while 316 steel pipes perform good. Therefore, it is not any kind of stainless steel that can resist corrosion and rust in any environment.
Stainless steel is a very thin, solid and stable and stable and stable chromium -enriched oxide film (protective film) formed by its surface to prevent the ability of oxygen atoms to continue to penetrate and continue to oxidize, and obtain the ability to rust. Once there is a reason, this film is continuously destroyed, and the oxygen at the air or liquid will continue to penetrate or the metal medium iron atom will continue to leave, forming a loose iron oxide, and the metal surface is constantly rusting. There are many forms that are damaged by this surface, and there are several commons in daily life: the following:
1. The surface of stainless steel is contained in dust or alien metal particles containing other metal elements. In the humid air, the condensed water between the adhesion and the stainless steel is connected to a micro -battery , The protective film is damaged, which is called electrochemical corrosion.
2. Stainless steel surface adheres to organic juice (such as melon vegetables, noodles, sputum, etc.). In the case of water oxygen, it constitutes organic acids and corrodes the metal surface for a long time.
3. The surface of stainless steel adhesive contains acid, alkali, and salt substances (such as alkaline water and limesty water splash on the decoration wall), causing local corrosion.
4. In polluting air (such as a large amount of vulcosion, carbon oxide, nitric oxide atmosphere), condense water, forming sulfuric acid, nitric acid, and acetic acid liquid points, causing chemical corrosion.
The above conditions can cause damage to the stainless steel surface protective membrane. Therefore, in order to ensure the permanent and light metal surface and not rust, we recommend:
1. It is necessary to clean the surface of the decorative stainless steel to remove the attachment to eliminate external factors that cause modification.
2. 316 stainless steels should be used in the seaside area, and 316 materials can resist seawater corrosion.
3. Some stainless steel pipe chemical ingredients in the market cannot meet the corresponding national standards, reaching 304