Performance and Usage of Titanium Materials Resistant to Crevice Corrosion

Abstract

The crevice corrosion in the chloride solutions at elevated temperatures is one of the important corrosion problems in titanium from the practical point of view. At present, Ti-0.15%Pd alloy, Ti-0.3%Mo-0.8 %Ni alloy and PdO/TiO₂-Ti (commercially pure titanium coated with a mixture of PdO and TiO₂) have been industrially used as countermeasure against the crevice corrosion. In this report, the crevice corrosion resistances of these three materials have been evaluated by means of immersion tests for crevice corrosion and electrochemical tests. The results have revealed that all of three materials showed a far more excellemt resistance than commercially pure titanium, and that Ti-0.15%Pd alloy and PdO/TiO₂-Ti were at the almost same level and a little superior to Ti-0.3%Mo-0.8%Ni alloy. Furthermore, a guideline for the effective usage of these materials, which might enable each material to exhibit its maximum advantage, has been proposed on the basis of the obtained corrosion resistance as well as the mechanical property and the service experience.