First, we shot this heat sink with gallium-tipped bullets, but it seemed even after a few days, those did not disperse enough gallium on the aluminum to do any damage. So I added just a couple drops of gallium to see what would happen.
As you can see, even a small amount of gallium will destroy a much larger chunk of aluminumiumum. 🙂 You can see why the general idea of a gallium-tipped bullet seemed completely feasible, at least in theory.
Gallium attacks most other metals by diffusing into their metal lattice. Gallium, for example, diffuses into the grain boundaries of aluminium-zinc alloys or steel, making them very brittle. Gallium easily alloys with many metals, and is used in small quantities as a plutonium-gallium alloy in the plutonium cores of nuclear bombs, to help stabilize the plutonium crystal structure. (per wikipedia)
Gallium can be bought at GalliumSource.com
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