Activated aluminum fuel
Aluminum can be used as a fuel source when reacted with water if its native surrounding oxide coating is penetrated with a gallium-based eutectic. When discrete aluminum objects are treated in a heated bath of eutectic, the eutectic penetrates the oxide coating. After the aluminum objects are treated, the aluminum objects can be reacted in a reactor to produce hydrogen which can, for example, react with oxygen in a fuel cell to produce electricity, for use in a variety of applications.
1. An activated aluminum fuel comprising:
a cold worked aluminum object defining a volume, the cold worked aluminum object containing a plastically deformed and non-recrystallized aluminum alloy having misaligned grains defining grain boundaries; and
a eutectic alloy including gallium and indium, the eutectic alloy along the misaligned grains of the plastically deformed and non-recrystallized aluminum alloy within the volume of the cold worked aluminum object, wherein the activated aluminum fuel is reactive with water to yield greater than about 80 percent and less than about 95 percent of a theoretical yield of hydrogen, and the eutectic alloy is greater than zero percent and less than about 3 percent of the total mass of the activated aluminum fuel.
2. The activated aluminum fuel of claim 1 , further comprising an aluminum oxide layer disposed on a surface of the cold worked aluminum object.
3. The activated aluminum fuel of claim 2 , wherein at least a portion of the aluminum oxide layer is exposed to air and free of the eutectic alloy.
4. The activated aluminum fuel of claim 1 , wherein the volume of the cold worked aluminum object forms a sphere.
5. The activated aluminum fuel of claim 1 , wherein the volume of the cold worked aluminum object forms a wire.
6. The activated aluminum fuel of claim 1 , wherein the volume of the cold worked aluminum object forms at least one of a sphere, a bar, a rectangular prism, a thin plate, or a cylinder.
7. The activated aluminum fuel of claim 1 , wherein, without the eutectic alloy, the cold worked aluminum object is greater than about 85 percent aluminum alloy by mass.
8. The activated aluminum fuel of claim 7 , wherein, without the eutectic alloy, the cold worked aluminum object is 7075 T6 aluminum alloy.
9. The activated aluminum fuel of claim 1 , wherein the misaligned grains have grain energy boundary greater than 0.5 J/m 2 .
10. The activated aluminum fuel of claim 1 , wherein the cold worked aluminum object includes an aluminum oxide layer forming an outer surface of the volume.
11. The activated aluminum fuel of claim 10 , wherein the aluminum oxide layer defines disruptions through which water is introducible into the misaligned grains in the volume of the cold worked aluminum object.
12. The activated aluminum fuel of claim 1 , wherein the eutectic alloy is about 22 percent by mass indium and about 78 percent by mass gallium.
13. The activated aluminum fuel of claim 1 , wherein the eutectic alloy further includes tin.
14. The activated aluminum fuel of claim 1 , wherein, with the eutectic alloy along the misaligned grains, the cold worked aluminum object factures at a stress less than the yield stress of the cold worked aluminum object in the absence of the eutectic alloy.