Abstract
Galvanic corrosion between titanium and a titanium-palldium alloy was studied by measuring the polarization characteristics and the weight loss by dipping in 0.5-1.0N HCl at 90°C. The following results were obtained: (1) When titanium was contacted with a titanium-palladium alloy, the corrosion rates of the both metals were almost the same at any concentration of HCl. When the concentration was 7N or higher, their corrosion rates were higher than that of titanium alone in HCl. (2) An active behavior was observed in the anodic polarization curve of titanium when the concentration of HCl was not lower than 1N, but the behavior was not observed in the alloy when the concentration was up to 8N. The coupled potential of titanium and the alloy was at a potential nobler than the critical potential for passivation of titanium in a dilute HCl up to about 3N. When the concentration was increased to 6-7N, the coupled potential was in the incomplete passivation region. When the concentration was 7N or higher, the coupled potential was at the peak current of passivation.
