Steel

Steel is a metalic alloy that consists mainly of iron and shares most of its features. While wrought iron typically consists of lees than a half percent carbon, in steel the petcentage is around one and a half percent carbon. With the increased carbon, steel is harder and has a much higher tensile strength that iron, but also more brittle. The first steels were probably created accidentally when the iron sword blanks were heated in charcoal forges. The original Japanese samurai steel sword blades were not steel as such, but a layered composite of wrought iron, and carbon which when worked created boundry layers of steel. Damascus steel, which was famous in ancient times for its flexibitity, was created from a number of different materials (some only in miniscule traces), essentially a complicated alloy with iron as main component.

While the ferrite allotrope of iron, which is normally what we see as wrought iron will not adsorb much carbon, when heated to a higher temperature, it becomes austenite? which is then capable of combining with carbon to form steel. Additional metals are usually added to carbon steel to change its charatistics. Nickel in steel adds to the tensle strength, Chromium increases the hardness, Vanadium also increases the hardness, while reducing the effects of metal fatigue.

There is also stainless steel, which does not rust, and isn't magnetic. It is an alloy of iron with chromium and vanadium.