(NURP) Investigation of chemical processes relating to the surface treatment of metallic powders to support the development of an aluminum-water undersea propulsion system

ABSTRACT: The goal of the work proposed herein is to investigate the surface chemistry associated with metallic aluminum powders as fuels for underwater applications through the Naval Undersea Research Program (NURP). Aluminum powder is a promising candidate to support underwater power, as it burns with a high energy density. In this application, the powder must be freely flowing; this has been successfully achieved through surface treatment of the particles. In this work, a framework will be established to allow for rational design of surface coatings of aluminum particles to yield the targeted fluid-like properties. In this manner, one could specify the desired properties for a given application, and then readily choose a formulation that provides these properties. This understanding of the aluminum particle surface coating, performance, and stability will help to determine the optimal chemical composition for fluid-like flow and longterm shelf-life. Additionally, successful coatings will be scaled to a larger batch size for application testing in a fluidized powder feeder. The objectives of this work are to: identify promising surface coatings based on fundamental surface science investigations on the small scale, produce powders with optimal bulk flow properties on the laboratory scale, and test the material in an application-specific fluidized feeder. The proposed team is the Applied Research Laboratory at The Pennsylvania State University to function as the laboratory mentor component and the Department of Chemistry at The Pennsylvania State University to function as the academic advisor component.