Definition - What does Alloy mean?
An alloy is metal composed of two or more elements, one of which must be a metal. Alloys are usually created by mixing these materials together in their molten form. The result is a uniform metal that has a combination of the physical, chemical and electrical properties of all the materials used to make the alloy.
Corrosionpedia explains Alloy
Alloys are created for many different reasons. Some alloys are created to increase mechanical properties such as strength or ductility. Other alloys are created because the material with all of the desired properties is too expensive to justify purchasing, so other elements are added to reduce cost, to the detriment of the desired properties. Quite commonly, alloys are created to increase the corrosion resistance of a material. For example, alloys with added chromium benefit from its corrosion resistant properties, even if the other elements in the alloy are not necessarily known for their corrosion resistance.
Common alloys include carbon steel, cast iron, tool steel, stainless steel, brass, bronze and certain grades of aluminum. There are many other alloys that can be created that have not been mentioned here.