Views:1 Author:Site Editor Publish Time: 2019-06-03 Origin:Site
Mr. Meng found that stainless steel products have become more and more popular in recent years. More and more customers and peers jumped into the stainless steel tube pit, I went with the flow. In case, this is a tuyere, may also follow a rise.
After the pit found that the stainless steel industry is also a relatively mature market. Plate, coil, pipe and other products have been developed relatively complete. Guangzhou, wuxi, tianjin and other places have also formed a certain scale effect.
But to be honest, stainless steel is really a good thing, because it does not rust, and look beautiful. As a kind of alloy steel tube, its future is very bright, at least I am very optimistic. For example, what was the earliest water pipe made of? Lead pipes, which have evolved into plastic pipes, so now many high-end buildings are using stainless steel pipes. With this point, it shows that, as the level of productivity and economic level of the promotion, stainless steel pipe is bound to have more use.
Okay, no more chatter, or it's time to put a little cross. Since the title of this article is "a few words let you understand stainless steel", so I strive to use the most straightforward and concise language, to introduce to you. Let's move on to the body.
All metals react with oxygen in the atmosphere to form an oxide film on the surface. Unfortunately, the iron oxide formed on ordinary carbon steel continues to oxidize, causing the corrosion to expand and eventually form holes. You can use paint or oxidation resistant metals (such as zinc, nickel and chromium) to protect the surface of carbon steel, but, as is known, this protection is only a thin film. If the protective layer is destroyed, the steel below will begin to rust, resistant to air, steam, water and other weak corrosion medium and acid, alkali, salt and other chemical corrosion medium corrosion steel. Also known as stainless acid - resistant steel. In practical application, the steel that is resistant to weak corrosive medium is often called stainless steel, and the steel that is resistant to chemical medium corrosion is called acid-resistant steel. Due to the difference in chemical composition, the former is not necessarily resistant to chemical medium corrosion, while the latter is generally rust free. The corrosion resistance of stainless steel 2 depends on the alloying elements contained in the steel. Chromium is the basic element to make stainless steel corrosion resistance, when the content of chromium in steel reaches about 12%, chromium and the oxygen in the corrosion medium, the formation of a very thin oxide film on the surface of steel (self-passivation film), can prevent the steel matrix further corrosion. In addition to chromium, common alloy elements include nickel, molybdenum, titanium, niobium, copper, nitrogen, etc.
Stainless steel is usually divided into the following four categories according to the matrix:
1, ferritic stainless steel. Contains 12% ~ 30% chromium. Its corrosion resistance, toughness and weldability increase with the increase of chromium content.
2, austenitic stainless steel. Chromium content is more than 18%, but also contains about 8% nickel and a small amount of molybdenum, titanium, nitrogen and other elements. Good comprehensive performance, can withstand many kinds of medium corrosion.
3, austenitic - ferrite duplex stainless steel. Both austenitic and ferritic stainless steels have the advantages of superplasticity.
4, martensitic stainless steel. High strength, but poor plasticity and weldability.