Corrosion behavior of brass immersed in CaCl2-LiBr-LiNO3/H2O blends

The corrosion effect of lithium bromide/water (LiBr/H2O) blended with calcium chloride (CaCl2) and lithium nitrate (LiNO3) over the brass surface was analyzed at 25, 50, and 80 °C. Electrochemical analyses such as electrochemical impedance spectroscopy (EIS), open circuit potential (OCP), and polarization curves (PC) were carried out. The EIS analyses showed that the brass immersed in LiNO3 + LiBr/H2O solution got the highest resistance with 2061, 2262, and 1511 Ωcm2 at 25, 50, and 80 °C, respectively. Also, the potentiodynamic analyses showed that the lower corrosion current (Icorr) was for the brass immersed in LiNO3 + LiBr/H2O solution with 1.80 × 10−3 mA/cm2 mainly due to LiNO3 modified the behavior of the cathodic branch due to the NO_3^- reduction, generating in the anodic branch a more prominent passivation zone than in LiBr/H2O. The CaCl2 + LiBr/H2O and CaCl2 + LiNO3 + LiBr/H2O solutions increased the corrosion process over the metal surface of the brass, increasing and decreasing the Icorr and Rp values calculated, respectively, due to Cl− ions forming a resistive insoluble and unstable compounds layer. The SEM micrographs reveal that the brass immersed in LiNO3 + LiBr/H2O solution got a less rough surface with pits less deep than in LiBr/H2O solution.