Corrosion characterization of Sn37Pb solders and with Cu substrate soldering reaction in 3.5wt.% NaCl solution

The electrochemical corrosion behavior of Sn37Pb solder, Cu₆Sn₅, Cu₃Sn and Cu in 3.5% NaCl solution was investigated by using Galvanic corrosion testing, potentiodynamic polarization methods. The galvanic current densities for Sn37Pb solder in 3.5 wt.% NaCl solution are 38, 16 and 5muA/cm² for Cu₃Sn, Cu, and Cu₆Sn₅, respectively. Polarization studies revealed that an increase in Cu content and formation of IMCs shifted the corrosion potential (E_corr.) towards more noble values and increased the corrosion current density (I_corr.).