|MadSci Network: Chemistry|
The strength of a sword is (chemically) a function of the (composition of the) metal alloy being used and (physically) of the methods used to handle this alloy.
Generally most swords are made from iron or steel. Too much carbon in the alloy, for example, will yield brittle metal. Too much of one material can yield metal that is easy to shape and decorate but very soft while too much of other materials gives metal that can not be easily shaped or handled.
The handling of the metal is also important. The strength is also a function of the crystal structure in the metal. A good metallurgist understands that proper "tempering" (slow cooling) after creating the sword will yield a better (stronger) product.
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