Stainless steel is a stainless steel (Stainless Steel) which is resistant to air, steam, water and other weak corrosive media and corrosive medium such as acid, alkali, salt and other chemical etching media, also known as stainless acid-resistant steel.
In practical applications, steel that is resistant to weak corrosive media is often referred to as stainless steel, while steel that is resistant to chemical media is referred to as acid-resistant steel. Due to the difference in chemical composition between the two, the former is not necessarily resistant to chemical media corrosion, while the latter generally has rust. The corrosion resistance of stainless steel depends on the alloying elements contained in the steel.
The basic alloying elements of stainless steel are nickel, molybdenum, titanium, niobium, copper, nitrogen, etc., to meet the requirements of stainless steel structure and performance for various purposes. Stainless steel is easily corroded by chloride ions. Because chromium, nickel and chlorine are isotopic elements, the isotope will be exchanged and assimilated to form corrosion of stainless steel.
The corrosion resistance of chemical composition stainless steel decreases with the increase of carbon content. Therefore, most of the stainless steel has a low carbon content, the maximum is not more than 1.2%, and some steels have a Wc (carbon content) of less than 0.03% ( Such as 00Cr12). The main alloying element in stainless steel is Cr (chromium), and steel has corrosion resistance only when the Cr content reaches a certain value. Therefore, stainless steel generally has a Cr (chromium) content of at least 10.5%.
Stainless steel also contains elements such as Ni, Ti, Mn, N, Nb, Mo, Si, Cu, etc. Stainless steel is not susceptible to corrosion, pitting, rust or wear. Stainless steel is also one of the strongest materials in building metal materials. Because stainless steel has good corrosion resistance, it enables structural components to permanently maintain engineering integrity. Chromium-containing stainless steel also combines mechanical strength and high extensibility, making it easy to machine parts to meet the needs of architects and structural designers.