The dual-phase steel flange is produced using dual-phase steel as the raw material. Dual-phase stainless steel refers to a solid solution structure where ferrite and austenite phases each account for about half. The content of the less abundant phase generally needs to reach 30%. With a low carbon content, the Cr content is typically between 18% and 28%, while the Ni content is between 3% and 10%. Some steels also contain alloying elements such as Mo, Cu, Nb, Ti, and N. This type of steel combines the characteristics of both austenitic and ferritic stainless steels. Compared to ferritic stainless steel, it has higher plasticity and toughness, no room temperature brittleness, and significantly improved intergranular corrosion resistance and welding performance. It also retains the 475°C brittleness of ferritic stainless steel and high thermal conductivity, as well as superplasticity.