aarondubrow (1866212) writes "Imagine a metal that “remembers” its original, cold-forged shape, and can return to that shape when exposed to heat or a magnetic pulse. Like magic out of a Harry Potter novel, such a metal could contract on command, or swing back and forth like a pendulum. Believe it or not, such metals already exist. First discovered in 1931, they belong to a class of materials called "shape memory alloys (SMA)," whose unique atomic make-up allows them to return to their initial form, or alternate between forms through a phase change."
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