2205 alloy is very weldable. The performance to be achieved by 2205 dual-phase steel is that the welded metal and the heat-modified part still maintain the same corrosion resistance, strength and toughness as the base metal. The welding of 2205 dual-phase 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.