ISO X2CrTi12 409L Stainless Steel Pipe Tube

Stainless steel is often divided according to its organizational state: martensitic steel, ferritic steel, austenitic steel, etc. In addition, it can be divided according to its composition: chromium stainless steel, chromium-nickel stainless steel, chromium-manganese-nitrogen stainless steel, etc.
1. Ferritic stainless steel: containing 12% to 30% chromium. Its corrosion resistance, toughness and weldability increase with the increase of chromium content, and its chloride stress corrosion resistance is better than other types of stainless steel. Belonging to this category are Cr17, Cr17Mo2Ti, Cr25, Cr25Mo3Ti, Cr28, etc. Because of its high chromium content, ferritic stainless steel has relatively good corrosion resistance and oxidation resistance, but poor mechanical and process properties. It is mostly used in acid-resistant structures with little stress and as anti-oxidation steel. This type of steel can resist corrosion from the atmosphere, nitric acid and salt water solutions, and has good high-temperature oxidation resistance and small thermal expansion coefficient. It is used in nitric acid and food factory equipment, and can also be used to make parts that work at high temperatures, such as gas turbine parts. .
2. Austenitic stainless steel: contains more than 18% chromium, and also contains about 8% nickel and a small amount of molybdenum, titanium, nitrogen and other elements. It has good comprehensive performance and can withstand corrosion from various media. Commonly used grades of austenitic stainless steel include 1Cr18Ni9, 0Cr19Ni9, etc. The wC of 0Cr19Ni9 steel is <0.08%, and the steel number is marked as "0". This type of steel contains a large amount of Ni and Cr, which makes the steel in an austenitic state at room temperature. This type of steel has good plasticity, toughness, weldability and corrosion resistance, and has good corrosion resistance in both oxidizing and reducing media. It is used to make acid-resistant equipment, such as corrosion-resistant containers and equipment linings, transportation pipelines, and Nitric acid equipment parts, etc. Austenitic stainless steel generally adopts solution treatment, that is, the steel is heated to 1050~1150℃ and then water-cooled to obtain a single-phase austenite structure.