EVALUATION OF IMPRESSED ELECTROMOTIVE FORCE CATHODIC PROTECTION
Abstract
Electromotive couples consisting of 0.064 in. x 24 in. x 24 in. bare 7075-T6 aluminum cathodes and 0.064 in. x 2 in. x 3 in. RC-70 titanium or equivalent platinum cathodes were separated from each other by a 0.065 in. x 8 in. dia. neoprene insulator, connected together with copper wire and immersed in sea water. In order to nullify the natural galvanic current, a regulated direct current was introduced into the copper portion of the circuit in such a manner that it opposed the galvanic current. In a series of tests wherein the impressed voltage and current was varied from specimen to specimen for periods ranging 2 to 16 days, the impressed currents failed to prevent corrosion of the 7075-T6 aluminum alloy. This was attributed to the formation of hydorxyl ions at the aluminum alloy cathode. These ions were believed corrosive to the aluminum alloy.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 28, 1957
- Accession Number
- AD0407738
Entities
People
- A. F. Hooper
- W. M. Sutherland
Organizations
- General Dynamics