Duplex stainless steel refers to stainless steel in which ferrite and austenite each account for about 50%, and generally the content of less phases needs to reach at least 30%. In the case of low C content, the Cr content is 18%~28%, and the Ni content is 3%~10%. Some steels also contain alloying elements such as Mo, Cu, Nb, Ti, and N.
Duplex stainless steel has the characteristics of both austenitic and ferritic stainless steel. Compared with ferrite, it has higher plasticity and toughness, no room temperature brittleness, significantly improved intergranular corrosion resistance and welding performance, while maintaining iron The body stainless steel is brittle at 475°C, has high thermal conductivity, and has the characteristics of superplasticity.
Compared with austenitic stainless steel, duplex stainless steel has high strength and significantly improved resistance to intergranular corrosion and chloride stress corrosion. Duplex stainless steel has excellent pitting corrosion resistance and is also a nickel-saving stainless steel.
Machinability of 2205 duplex stainless steel
On high-speed machine tools, the feed rate and cutting speed of 2205 duplex stainless steel are the same as 316L stainless steel. If a carbonized knife is used, the cutting speed is reduced by about 20% compared with 316L stainless steel, and the performance of the machine equipment and its components plays a key role here.
Welding of 2205 duplex stainless steel
The weldability of 2205 duplex stainless steel is very good. The performance to be achieved by 2205 duplex stainless steel is that the welded metal and heat-modified parts still maintain the same corrosion resistance, strength and toughness as the base metal. The welding of 2205 duplex stainless steel is not difficult, but its welding procedure needs to be designed so that after welding, it can maintain a good phase balance state and avoid the precipitation of harmful metal phase or non-metal phase.
