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Steel is an alloy composed of between 0.2 and 2.0 percent carbon, with the balance being iron. From prehistory through the creation of the blast furnace, iron was produced from iron ore as wrought iron, 99.82–100 percent Fe, and the process of making steel involved adding carbon to iron, usually in a serendipitous manner, in the forge, or via the cementation process.
Bloomery smelting during the Middle Ages.. Ferrous metallurgy is the metallurgy of iron and its alloys.The earliest surviving prehistoric iron artifacts, from the 4th millennium BC in Egypt, [1] were made from meteoritic iron-nickel. [2]
Consequently, at the temperatures needed to reduce zinc oxide to the metal, the metal is already gaseous. [23] [24] Arsenic sublimes at 615 °C (1137 °F), passing directly from the solid state to the gaseous state. [21] Antimony melts at 631 °C (1167 °F) [21] Platinum melts at 1768 °C (3215 °F), even higher than iron. [21]
To inhibit corrosion, at least 11% chromium can be added to steel so that a hard oxide forms on the metal surface; this is known as stainless steel. Tungsten slows the formation of cementite , keeping carbon in the iron matrix and allowing martensite to preferentially form at slower quench rates, resulting in high-speed steel .
The use of cork, which has been recently added to the category of materials science, had its first mentions beginning with Horace, Pliny, and Plutarch. [10] It had many uses in antiquity including in fishing and safety devices because of its buoyancy, an engraving medium, sandal soles to increase stature, container stoppers, and being an insulator.
In this system, high-purity wrought iron, charcoal, and glass were mixed in crucibles and heated until the iron melted and absorbed the carbon. The resulting high-carbon steel, called fūlāḏ by the Arabs (Arabic: فولاذ, romanized: fūlāḏ, lit. 'steel; wootz') and wootz by later Europeans, was exported throughout much of Asia and Europe.
A metal (from Ancient Greek μέταλλον (métallon) 'mine, quarry, metal') is a material that, when polished or fractured, shows a lustrous appearance, and conducts electricity and heat relatively well.
Metallurgy derives from the Ancient Greek μεταλλουργός, metallourgós, "worker in metal", from μέταλλον, métallon, "mine, metal" + ἔργον, érgon, "work" The word was originally an alchemist's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia ...