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Can submersible vessel with copper/titanium interface be improved by plating?

2003

I am working on a design for a submersible optical vessel. The power distribution unit (PDU) has the potential to generate 200 W of thermal energy. We have designed to dissipate the bulk of this heat to the sea by way of conduction. The core of the PDU is being made of oxygen free copper. It is attached to the titanium hull with mechanical fasteners.

I would appreciate any advice or input regarding the possibility of dissimilar metal corrosion. I realize the situation is not horrible but intend to plate the copper to avoid environmental corrosion. The plan is to apply plating such as an electrolytic nickel process to the copper. I believe the dissimilar metal situation is worsened by this application. Please advise on other more favorable processes, if known.

Thank you,

James Harper
mechanical design engineer - Tucson, Arizona, USA

CP titanium is the answer for sea water.

Skip Schaefer
heaters and controls - Oxnard, California, USA
2003

The dissimilar metal corrosion will take place - copper will be suffered but the level of the phenomenon is dependent on the square rates. The best way is to made all of the items of titanium. If that is impossible I would recommend you to shield titanium by local oxidation procedure. The method is known and we use it many times including for a highly demandable apparatuses for sea water.

Andrey
- St.Petersburg, Russia
2004