EUTECTOID STEEL

Steel representing the eutectoid composition of the iron – carbon system, with about 0.80% to 0.83% carbon, the eutectoid temperature being about 1333° F. Such steel in the annealed condition consists exclusively of pearlite. Steels with less than this quota of carbon are known as hypo-eutectoid and contain free ferrite in addition to the pearlite. When more carbon is present, the steel is known as hyper-eutectoid and contains free cementite. The presence of certain elements, such as nickel or chromium, lowers the eutectoid carbon content.