Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys.
Metallurgy encompasses both the science and the technology of metals, including their production and the engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking by providing it with a scientific foundation, much as medical science supports the practice of medicine. A specialist practitioner of metallurgy is known as a metallurgist.
The science of metallurgy is further subdivided into two broad categories: chemical metallurgy and physical metallurgy. Chemical metallurgy is chiefly concerned with the reduction and oxidation of metals, and the chemical performance of metals. Subjects of study in chemical metallurgy include mineral processing, the extraction of metals, thermodynamics, electrochemistry, and chemical degradation (corrosion). In contrast, physical metallurgy focuses on the mechanical properties of metals, the physical properties of metals, and the physical performance of metals. Topics studied in physical metallurgy include crystallography, material characterization, mechanical metallurgy, phase transformations, and failure mechanisms.
Historically, metallurgy has predominantly focused on the production of metals. Metal production begins with the processing of ores to extract the metal, and includes the mixture of metals to make alloys. Metal alloys are often a blend of two or more metallic elements. However, non-metallic elements are often added to alloys in order to achieve properties suitable for an application. The study of metal production is subdivided into ferrous metallurgy (also known as black metallurgy) and non-ferrous metallurgy, also known as colored metallurgy.
Ferrous metallurgy involves processes and alloys based on iron, while non-ferrous metallurgy involves processes and alloys based on other metals. The production of ferrous metals accounts for 95% of world metal production.
Modern metallurgists work in both emerging and traditional areas as part of an interdisciplinary team alongside material scientists and other engineers. Some traditional areas include mineral processing, metal production, heat treatment, failure analysis, and the joining of metals (including welding, brazing, and soldering). Emerging areas for metallurgists include nanotechnology, superconductors, composites, biomedical materials, electronic materials (semiconductors) and surface engineering.
Etymology and pronunciation
Metallurgy derives from the Ancient Greek , , "worker in metal", from , , "mine, metal" + , , "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 Britannica.
In the late 19th century, metallurgy's definition was extended to the more general scientific study of metals, alloys, and related processes. In English, the pronunciation is the more common one in the United Kingdom while pronunciation is the more common one in the United States and is the first-listed variant in various American dictionaries, including Merriam-Webster Collegiate and American Heritage.
History
thumb|Artefacts from the [[Varna Necropolis in present-day Bulgaria]]
thumb|The mining areas of the ancient [[Middle East with arsenic (in brown), copper (in red), tin (in grey), iron (in reddish brown), gold (in yellow), silver (in white), lead (in black), arsenic bronze (in yellow), and tin bronze (in grey)]]
The earliest metal employed by humans appears to be gold, which can be found "native". Small amounts of natural gold, dating to the late Paleolithic period, have been found in Spanish caves. Silver, copper, tin and meteoric iron can also be found in native form, allowing a limited amount of metalworking in early cultures. Early cold metallurgy, using native copper that was not smelted from ore has been documented at sites in Anatolia and at the site of Tell Maghzaliyah in Iraq, dating from the 7th~6th millennia BCE. Certain metals, such as tin, lead, and copper can be recovered from their ores by simply heating the rocks in a comparatively moderate-temperature fire or blast furnace in a process known as smelting. The first evidence of copper smelting, dating from the has been found at archaeological sites in Majdanpek, Jarmovac, and Pločnik, in present-day Serbia. The Balkans and adjacent Carpathian region were the location of major Chalcolithic cultures including Vinča, Varna, Karanovo, Gumelnița and Hamangia, which are often grouped together under the name of 'Old Europe'. With the Carpatho-Balkan region described as the 'earliest metallurgical province in Eurasia', its scale and technical quality of metal production in the totally overshadowed that of any other contemporary production centre.