Aluminum Alloy Conditioning to Improve the Corrosion Resistance of Torpedo Fuel Tanks

A large portion of the maintenance costs of exercised torpedoes are attributable to the condition based maintenance of torpedo fuel tanks. In addition to consuming limited financial and manpower resources, corrosion impacts mission capability and asset readiness by reducing operational availability and their performance envelope. During use, the fuel tank is backfilled with seawater and a reaction between the seawater and chemicals in the Otto II fuel occurs, which has been demonstrated to accelerate the corrosion process. In this program, Luna proposes to develop an aluminum alloy surface conditioning process that will improve the inherent corrosion resistance of torpedo alloy systems. When used in conjunction with the current protective coatings, improved corrosion performance can be expected, thereby decreasing corrosion life cycle costs. The Phase I development efforts will focus on optimizing the conditioner chemistry for alloys of use in torpedo fuel tanks, such as AA 7175, integrating the conditioner step into the coating process, and characterizing the improved corrosion performance.