reza peykari

In this study, the corrosion behavior and microstructural variations of two-layer sheets consisting of 304 stainless steel copper have been investigated after the explosive welding process. Explosive welding is carried out by variable explosive charges and changing the distance between the sheets. To investigate the corrosion behavior of the welding zone, dynamic potential polarization and electrochemical impedance imaging were used. Besides, to perform microstructural analysis, metallographic tests using an optical microscope and scanning electron microscope (SEM) were employed. In addition, micro-hardness is considered to investigate the effect of shock waves caused by the explosion. The results showed that the sample with an explosive thickness of 79 mm has the highest interface hardness (HV 549) due to the high thickness of the explosive layer and standoff distance (3 mm). Also, the polarization test results indicated that the lowest corrosion rate corresponds to the sample with an explosive charge thickness of 79 mm and a standoff distance of 2 mm, and the highest corrosion rate was related to the sample with a 46-mm explosive charge thickness and standoff distance of 3 mm. Based on the results obtained from the electrochemical impedance spectroscopy, It can be concluded that by increasing the amount of copper in the locally frozen melt of the samples, the intensity of corrosion caused by the galvanic cell increases.