An alloy is a solid solution or homogeneous mixture of two or more elements, at least one of which is a metal, which itself has metallic properties. It usually has different properties from those of its component elements. Alloying one metal with others often enhances its properties. For instance, steel is stronger than iron, its primary element. The physical properties, such as density, reactivity, Young's modulus, and electrical and thermal conductivity, of an alloy may not differ greatly fr… (More on Alloy)