Preparation of Macro Metallographic Samples of Duplex Stainless Steel Welded Joints

The macro metallographic morphology of duplex stainless steel welded joints was not clear by using the macro metallographic sampling method recommended in the standard. The electrolytic corrosion method was applied to the preparation of macro metallographic samples of duplex stainless steel welded joints, and the appropriate electrolyte and electrolytic corrosion parameters were determined by tests. The results show that macro metallographic samples of duplex stainless steel welded joints with clear visible in different regions could be obtained under the conditions of electrolyte of 10 mL HNO₃ solution+90 mL H₂O+1 g NaCl, current density of 1.11 mA ·mm^-2 and corrosion time of 2 min.