Corrosion Resistance of the Joint of Stainless Steels in Aggressive Solution

The CO2 laser welding technique was proposed as a method of joining dissimilar materials. The corrosion resistance of the joint of TP347HFG and VM12-SHC stainless steels in chloride solution was investigated. The stainless steels were butt welded. The materials were examined by electrochemical methods. The microstructure of the weld and the heat-affected zones were observed in an optical (OM) and scanning electron microscope (SEM). The X-ray fluorescence spectrometer (XRF) was used to determine variations in the main chemical elements across the fillet weld. The results showed a substantial intermixing of both substrates within the fusion zone. The joint in the environment of strong electrolytes of Cl- corrodes according to the electrochemical mechanism. The corrosion kinetic parameters for the substrates were calculated and discussed. The joint possesses medium resistance to electrochemical corrosion in relation to both steels.