Stainless steel is one of the most important inventions in the 20th century, during the past hundred years of development and research has formed a series of more than 300 brand of steel grade. Visible, as an important material of stainless steel becomes more and more important for people, it is installed in engineering materials plays a role can not be ignored. Stainless steel elbow, of course, as a kind of pipe installation accessories products, plays an important role.
As we all know, stainless steel elbow is different from carbon steel elbow is the main material of different. The chemical composition of the stainless steel elbow will keep the bend surface for a long time without rust. Then what metal elements can make the stainless steel elbow so good with carbon steel elbow it?
We all know that the industrial grade stainless steel elbow is austenitic stainless steel. Austenitic stainless steel is greater than 18%, and chromium containing 8% nickel, of course, which also contains a small amount of copper, titanium, nitrogen and other elements. This kind of steel contains a large amount of nickel and chromium to make steel at room temperature in a state of austenite. Visible, chromium and nickel in stainless steel play an important role.
Now we talk about the role of chromium in the stainless steel elbow: stainless steel elements is decided only one is Cr, so far, no chromium stainless steel, add chromium in stainless steel, the contradiction of internal corrosion resistance, resistance to damage the direction of development. The addition of chromium content in the steel reached more than 10 in order to form chromium passivation protective membrane stability, protection of steel against atmospheric corrosion, corrosion resistance of stainless steel increased with increasing chromium content.
Then we talk about the role of nickel in stainless steel elbow: nickel is an excellent corrosion resistant material, which is an important alloying element in alloy steel. Nickel in stainless steel to join, the crystal structure changes from cubic face centered cubic structure, the steel is easy to form a single organization (austenite) steel, has not formed the micro battery capacity, so as to avoid being the main reasons for the corrosion of steel. In stainless steel, if the nickel can reach 24%, the microstructure of pure austenite can be obtained, and the corrosion resistance of the steel in some medium can be significantly changed by 27%. However, nickel and chromium exist in stainless steel, nickel can play a lot of valuable role in stainless steel.
Source: Yaang Pipe Industry Co., Limited (www.yaang.com)