The tube has good welding properties ofduplex stainless steel pipes, compared with ferrite stainless steel and austenitic stainless steel, it is not like a ferritic stainless steel welding heat affected zone, because of grain coarsening and make serious plasticity and toughness greatly reduced, is not as sensitive to austenitic stainless steel, welding hot crack.

双相不锈钢由于其特殊的优点，广泛应用于石油化工设备、海水与废水处理设备、输油输气管线、造纸机械等工业领域，近年来也被研究用于桥梁承重结构领域，具有很好的发展前景。

Double phase stainless steel because of its special advantages, is widely used in oil and petrochemical equipment, water and wastewater treatment equipment, pipelines, machinery and other industrial fields, in recent years has also been used in the field of bridge bearing structure, has good prospects for development.

双相不锈钢是在其固淬组织中铁素体相与奥氏体相各占一半，一般最少相的含量也许要达到30%。

Duplex stainless steel pipe is quenched in the solid ferrite and austenite phase of each half, the general minimum phase content may reach 30%.