الفهرس 
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Abstract
The pitting corrosion of copper in both LiBr and NaBr solutions has been studied using potentiodynamic measurements and surface analysis techniques. It was found that pitting of Cu was evident only after the formation of a protective film of CuO and/or Cu(OH)2, depending on the bromide content. In case of NaBr the hysteresis loop of pitting corrosion started to appear at 3.1×10-2M while in case of LiBr it started at 7.4×10-2M bromide content. These results, together with the current – time trend and the surface analysis, confirm the role of Li+ on the passivation and pitting attack on copper metal. Results also showed that up to 5x10-1M passivity was more evident and pitting corrosion took place. At 7x10-1M LiBr, some evidence of limited passivity was seen which is followed by pitting corrosion. At more anodic potential (≈ 900mV) general dissolution takes place. As the concentration of LiBr increased from 1 to 9M, the dissolution started to appear with pitting which changed with higher rate to general depending on the concentration. On the other hand, the effect of temperature of 25, 50, 70 and 80°C on the dissolution of Cu in different concentration of LiBr also investigated. The results showed fourth types of corrosion forms are detected as; the first one is the general dissolution due to complexing formation of soluble CuBr2- . The second type is the pitting, the third type is the metastable pitting type while the last one is the second type of general form due to autocatalytic dissolution of Cu+. On the other hand, the effect of different concentrations of LiBr on the dissolution of Cu-base alloys of Cu/7Al, Cu/30Zn, Cu/10Ni and Cu/30Ni was studied. The potentiodynamic cyclic polarization measurements shows that, for one and the same alloy as increasing the temperature the corrosion potential shifted to more negative potential and the corrosion current density attained higher value. In addition, Cu/30Ni is the more resistance one in comparison with other alloys.