Why are rusting stainless steel pipe when the surface rust brown dots, people great surprise: that "Stainless steel is not rusty, rusty steel is not, and may in fact be a problem with steel, which. stainless steel is a lack of understanding of the views of a one-sided bias.
 
      Under certain conditions, stainless steel will rust in. Stainless steel has the ability to resist the atmospheric oxidation --- ie stainless steel, while also having the acid, the medium is the ability to salt corrosion --- namely corrosion resistance. But the size of its corrosion resistance of the steel itself is with its chemical composition, plus inter-state media types and environmental conditions changed. Steels such as 304, in a clean dry atmosphere, there is absolutely excellent anti-corrosion ability, but move it to the waterfront area, contains a lot of salt in the sea of fog, will soon rust; while 316 steel is performing well . Therefore, not any kind of stainless steel, in any environment resistant to the corrosive

      Not rusting stainless steel is an alloy of iron, chromium, carbon, and composed of many different elements , the main component elements of iron , chromium is first major alloying element . Generally , at least the chromium content of more than 11% to as stainless steel, because the chromium content is less , then the stainless steel outer dense layer will not form a protective film of chromium oxide , the loss of corrosion rust ﹝ ﹞ function. If sufficient chromium content in the atmosphere at room temperature , is not rusty . Stainless steel is a very thin layer of fine , stable and sturdy attachment chromium oxide film ( protective film ) is formed by a surface , to prevent further penetration of oxygen atoms , to oxidation , corrosion resistance to be obtained . Once there is some reason , this film was constantly undermined , air or liquid oxygen atoms will continue to infiltrate or metal from iron atoms constantly analyze , forming loose iron oxide, metal surface corrosion will continue to suffer . When the stainless steel surface with attachments containing the accumulated dust or other metallic elements heterogeneous metal particles in the humid air , condensate and stainless steel fixtures between the two together into a micro- battery , causing the electrochemical reaction , protective film is damaged, call it that electrochemical corrosion, real life, metal corrosion engineering practice , the vast majority belong to electrochemical corrosion.