Platinum-faced Titanium for Electrochemical Anodes

The good resistance of titanium to corrosion cannot be better illustrated than by its behaviour in sea-water in which it is virtually immune to attack (I), and from this it might be logical to suppose that the metal would form an excellent anode for impressed current cathodic protection of structures such as steel jetties, under-water pipelines and ships' hulls. In point of fact, the protective surface film on titanium has peculiar properties. It is resistant to the passage of current into an electrolyte, but it has low resistivity when a second metal makes contact with it. If an attempt is made to use titanium as an anode in salt water, this resistance to the passage of current into the electrolyte immediately becomes apparent for, as shown in Fig. I, an