||(Anglo-Saxon, iron; L. ferrum) Iron was used prehistorically:
- Genesis mentions that Tubal-Cain, seven generations from Adam, was
"an instructor of every artificer in brass and iron."
- A remarkable iron pillar, dating to about A.D. 400, remains
standing today in Delhi, India. This solid shaft of wrought iron is
about 7 1/4 m high by 40 cm in diameter. Corrosion to the pillar has
been minimal although it has been exposed to the weather since its
||The pure metal is very reactive chemically and rapidly corrodes,
especially in moist air or at elevated temperatures. It has four
allotropic forms or ferrites, known as alpha, beta, gamma, and omega,
with transition points at 700, 928, and 1530C. The alpha form is
magnetic, but when transformed into the beta form, the magnetism
disappears although the lattice remains unchanged. The relations of
these forms are peculiar. Pig iron is an alloy containing about 3
percent carbon with varying amounts of Sulfur, Silicon, Manganese,
Iron is hard, brittle, fairly fusible, and is used to produce other
alloys, including steel. Wrought iron contains only a few tenths of a
percent of carbon,
is tough, malleable, less fusible, and has usually a "fibrous"
Carbon steel is an alloy of iron with small amounts of Mn, S, P, and
Si. Alloy steels are carbon steels with other additives such as nickel, chromium, vanadium,
etc. Iron is a cheap, abundant, useful, and important metal.