alloy steel

alloy steel (countable and uncountable, plural alloy steels)

2. Any of many steels whose alloy composition includes other elements besides the iron and carbon that all steels have, in order to improve the mechanical properties of the material.

   Hypernyms: steel < metal < material

   Hyponym: stainless steel

   Coordinate term: carbon steel

Although every steel is an alloy, not all steels are called "alloy steels". The simplest steels are iron (Fe) alloyed with carbon (C) (about 0.1% to 1%, depending on type) and nothing else (excepting negligible traces via slight impurities); these are called carbon steels. However, the term "alloy steel" is the standard term referring to steels with other alloying elements added deliberately in addition to the carbon. Common alloyants include manganese (the most common one), nickel, chromium, molybdenum, vanadium, silicon, and boron. Less common alloyants include aluminium, cobalt, copper, cerium, niobium, titanium, tungsten, tin, zinc, lead, and zirconium.