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50-455: In metallurgy , non-ferrous metals are metals or alloys that do not contain iron ( allotropes of iron , ferrite , and so on) in appreciable amounts. Generally more costly than ferrous metals, non-ferrous metals are used because of desirable properties such as low weight (e.g. aluminium ), higher conductivity (e.g. copper ), non- magnetic properties or resistance to corrosion (e.g. zinc ). Some non-ferrous materials are also used in

100-532: A crucible . Gold, silver and copper replaced some of the functions of other resources, such as wood and stone, owing to their ability to be shaped into various forms for different uses. Due to their rarity, these gold, silver and copper artifacts were treated as luxury items and handled with great care. The use of copper also heralded the transition from the Stone Age to the Copper Age . The Bronze Age , which succeeded

150-859: A bar or block using a mold chill method. A special case are polycrystalline or single crystal ingots made by pulling from a molten melt. Single crystal ingots (called boules ) of materials are grown (crystal growth) using methods such as the Czochralski process or Bridgeman technique . The boules may be either semiconductor (e.g. electronic chip wafers , photovoltaic cells ) or non-conducting inorganic compounds for industrial and jewelry use (e.g., synthetic ruby, sapphire). Single crystal ingots of metal are produced in similar fashion to that used to produce high purity semiconductor ingots, i.e. by vacuum induction refining. Single crystal ingots of engineering metals are of interest due to their very high strength due to lack of grain boundaries . The method of production

200-830: A blend of at least two different 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

250-507: A burial site located in the western industrial zone of Varna , approximately 4 km from the city centre, internationally considered one of the key archaeological sites in world prehistory. The oldest gold treasure in the world, dating from 4,600 BC to 4,200 BC, was discovered at the site. The gold piece dating from 4,500 BC, found in 2019 in Durankulak , near Varna is another important example. Other signs of early metals are found from

300-410: A ductile to brittle transition and lose their toughness, becoming more brittle and prone to cracking. Metals under continual cyclic loading can suffer from metal fatigue . Metals under constant stress at elevated temperatures can creep . Cold-working processes, in which the product's shape is altered by rolling, fabrication or other processes, while the product is cold, can increase the strength of

350-426: A larger contact area. Molds may be either solid "massive" design, sand cast (e.g. for pig iron), or water-cooled shells, depending upon heat transfer requirements. Ingot molds are tapered to prevent the formation of cracks due to uneven cooling. A crack or void formation occurs as the liquid to solid transition has an associated volume change for a constant mass of material. The formation of these ingot defects may render

400-413: A liquid bath. Metallurgists study the microscopic and macroscopic structure of metals using metallography , a technique invented by Henry Clifton Sorby . In metallography, an alloy of interest is ground flat and polished to a mirror finish. The sample can then be etched to reveal the microstructure and macrostructure of the metal. The sample is then examined in an optical or electron microscope , and

450-401: A major concern. Cast irons, including ductile iron , are also part of the iron-carbon system. Iron-Manganese-Chromium alloys (Hadfield-type steels) are also used in non-magnetic applications such as directional drilling. Other engineering metals include aluminium , chromium , copper , magnesium , nickel , titanium , zinc , and silicon . These metals are most often used as alloys with

500-615: A smelted copper axe dating from 5,500 BC, belonging to the Vinča culture . 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

550-563: A superior metal could be made, an alloy called bronze . This represented a major technological shift known as the Bronze Age . The extraction of iron from its ore into a workable metal is much more difficult than for copper or tin. The process appears to have been invented by the Hittites in about 1200 BC, beginning the Iron Age . The secret of extracting and working iron was a key factor in

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600-401: Is a chemical surface-treatment technique. It involves bonding a thin layer of another metal such as gold , silver , chromium or zinc to the surface of the product. This is done by selecting the coating material electrolyte solution, which is the material that is going to coat the workpiece (gold, silver, zinc). There needs to be two electrodes of different materials: one the same material as

650-443: Is an industrial coating process that consists of a heat source (flame or other) and a coating material that can be in a powder or wire form, which is melted then sprayed on the surface of the material being treated at a high velocity. The spray treating process is known by many different names such as HVOF (High Velocity Oxygen Fuel), plasma spray, flame spray, arc spray and metalizing. Electroless deposition (ED) or electroless plating

700-406: 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

750-708: Is collected and processed to extract valuable metals. Ore bodies often contain more than one valuable metal. Tailings of a previous process may be used as a feed in another process to extract a secondary product from the original ore. Additionally, a concentrate may contain more than one valuable metal. That concentrate would then be processed to separate the valuable metals into individual constituents. Much effort has been placed on understanding iron –carbon alloy system, which includes steels and cast irons . Plain carbon steels (those that contain essentially only carbon as an alloying element) are used in low-cost, high-strength applications, where neither weight nor corrosion are

800-455: Is defined as the autocatalytic process through which metals and metal alloys are deposited onto nonconductive surfaces. These nonconductive surfaces include plastics, ceramics, and glass etc., which can then become decorative, anti-corrosive, and conductive depending on their final functions. Electroless deposition is a chemical processes that create metal coatings on various materials by autocatalytic chemical reduction of metal cations in

850-644: Is found in the Balkans and Carpathian Mountains , as evidenced by findings of objects made by metal casting and smelting dated to around 6000-5000 BC. Certain metals, such as tin, lead, and copper can be recovered from their ores by simply heating the rocks in a fire or blast furnace in a process known as smelting. The first evidence of copper smelting, dating from the 6th millennium BC, has been found at archaeological sites in Majdanpek , Jarmovac and Pločnik , in present-day Serbia . The site of Pločnik has produced

900-530: Is the more common one in the United Kingdom . The / ˈ m ɛ t əl ɜːr dʒ i / pronunciation is the more common one in the United States US and is the first-listed variant in various American dictionaries, including Merriam-Webster Collegiate and American Heritage . The earliest metal employed by humans appears to be gold , which can be found " native ". Small amounts of natural gold, dating to

950-644: Is via single crystal dendrite and not via simple casting. Possible uses include turbine blades . In the United States, the brass and bronze ingot making industry started in the early 19th century. The US brass industry grew to be the number one producer by the 1850s. During colonial times the brass and bronze industries were almost non-existent because the British demanded all copper ore be sent to Britain for processing. Copper based alloy ingots weighed approximately 20 pounds (9.1 kg). Ingots are manufactured by

1000-518: The 6th–5th millennia BC totally overshadowed that of any other contemporary production centre. The earliest documented use of lead (possibly native or smelted) in the Near East dates from the 6th millennium BC, is from the late Neolithic settlements of Yarim Tepe and Arpachiyah in Iraq . The artifacts suggest that lead smelting may have predated copper smelting. Metallurgy of lead has also been found in

1050-642: The Balkans during the same period. Copper smelting is documented at sites in Anatolia and at the site of Tal-i Iblis in southeastern Iran from c. 5000 BC. Copper smelting is first documented in the Delta region of northern Egypt in c. 4000 BC, associated with the Maadi culture . This represents the earliest evidence for smelting in Africa. The Varna Necropolis , Bulgaria , is

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1100-506: The Copper Age, was again heralded by the invention of bronze , an alloy of copper with the non-ferrous metal tin . Non-ferrous metals are used in residential, commercial and industrial applications. Material selection for a mechanical or structural application requires some important considerations, including how easily the material can be shaped into a finished part and how its properties can be either intentionally or inadvertently altered in

1150-472: The amount of phases present as well as the degree of strain to which a sample has been subjected. Current advanced characterization techniques, which are used frequently in this field are: Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Electron Backscattered Diffraction (EBSD) and Atom-Probe Tomography (APT). Ingot Ingots are generally made of metal, either pure or alloy, heated past its melting point and cast into

1200-415: The cast and wrought forms of the same metal or alloy. Metallurgy 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 the production of metals and

1250-426: The cast ingot useless and may need to be re-melted, recycled, or discarded. The physical structure of a crystalline material is largely determined by the method of cooling and precipitation of the molten metal. During the pouring process, metal in contact with the ingot walls rapidly cools and forms either a columnar structure or possibly a "chill zone" of equiaxed dendrites , depending upon the liquid being cooled and

1300-416: The coating material and one that is receiving the coating material. Two electrodes are electrically charged and the coating material is stuck to the work piece. It is used to reduce corrosion as well as to improve the product's aesthetic appearance. It is also used to make inexpensive metals look like the more expensive ones (gold, silver). Shot peening is a cold working process used to finish metal parts. In

1350-461: The cooling of a molten liquid (known as the melt) in a mold. The manufacture of ingots has several aims. Firstly, the mold is designed to completely solidify and form an appropriate grain structure required for later processing, as the structure formed by the cooling of the melt controls the physical properties of the material. Secondly, the shape and size of the mold is designed to allow for ease of ingot handling and downstream processing. Finally,

1400-429: The cooling rate of the mold. For a top-poured ingot, as the liquid cools within the mold, differential volume effects cause the top of the liquid to recede leaving a curved surface at the mold top which may eventually be required to be machined from the ingot. The mold cooling effect creates an advancing solidification front, which has several associated zones, closer to the wall there is a solid zone that draws heat from

1450-490: The engineering of metal components used in products for both consumers and manufacturers. Metallurgy is distinct from the craft of metalworking . Metalworking relies on metallurgy in a similar manner to how medicine relies on medical science for technical advancement. 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

1500-470: The first metals used by humans for metallurgy. Gold, silver and copper existed in their native crystalline yet metallic form. These metals, though rare, could be found in quantities sufficient to attract the attention of humans. Less susceptible to oxygen than most other metals, they can be found even in weathered outcroppings. Copper was the first metal to be forged; it was soft enough to be fashioned into various objects by cold forging and could be melted in

1550-619: The highly developed and complex processes of mining metal ores, metal extraction, and metallurgy of the time. Agricola has been described as the "father of metallurgy". Extractive metallurgy is the practice of removing valuable metals from an ore and refining the extracted raw metals into a purer form. In order to convert a metal oxide or sulphide to a purer metal, the ore must be reduced physically, chemically , or electrolytically . Extractive metallurgists are interested in three primary streams: feed, concentrate (metal oxide/sulphide) and tailings (waste). After mining, large pieces of

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1600-402: The image contrast provides details on the composition, mechanical properties, and processing history. Crystallography , often using diffraction of x-rays or electrons , is another valuable tool available to the modern metallurgist. Crystallography allows identification of unknown materials and reveals the crystal structure of the sample. Quantitative crystallography can be used to calculate

1650-905: The iron and steel industries. For example, bauxite is used as flux for blast furnaces , while others such as wolframite , pyrolusite , and chromite are used in making ferrous alloys. Important non-ferrous metals include aluminium, copper, lead , tin , titanium , and zinc, and alloys such as brass . Precious metals such as gold , silver , and platinum and exotic or rare metals such as mercury , tungsten , beryllium , bismuth , cerium , cadmium , niobium , indium , gallium , germanium , lithium , selenium , tantalum , tellurium , vanadium , and zirconium are also non-ferrous. They are usually obtained through minerals such as sulfides , carbonates , and silicates . Non-ferrous metals are usually refined through electrolysis . Due to their extensive use, non-ferrous scrap metals are usually recycled . The secondary materials in scrap are vital to

1700-501: 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 . Metallurgy derives from the Ancient Greek μεταλλουργός , metallourgós , "worker in metal", from μέταλλον , métallon , "mine, metal" + ἔργον , érgon , "work" The word

1750-555: The late Paleolithic period, 40,000 BC, 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 not melted from mineral has been documented at sites in Anatolia and at the site of Tell Maghzaliyah in Iraq , dating from the 7th/6th millennia BC. The earliest archaeological support of smelting (hot metallurgy) in Eurasia

1800-621: The liquid melt alloy compositions. Continuous casting methods for ingot processing also exist, whereby a stationary front of solidification is formed by the continual take-off of cooled solid material, and the addition of a molten liquid to the casting process. Approximately 70 percent of aluminium ingots in the U.S. are cast using the direct chill casting process, which reduces cracking. A total of 5 percent of ingots must be scrapped because of stress induced cracks and butt deformation. Plano-convex ingots are widely distributed archaeological artifacts which are studied to provide information on

1850-413: The metallurgy industry, as the production of new metals often needs them. Some recycling facilities re-smelt and recast non-ferrous materials; the dross is collected and stored onsite while the metal fumes are filtered and collected. Non-ferrous scrap metals are sourced from industrial scrap materials, particle emissions and obsolete technology (for example, copper cables ) scrap. Non-ferrous metals were

1900-452: The mold is designed to minimize melt wastage and aid ejection of the ingot, as losing either melt or ingot increases manufacturing costs of finished products. A variety of designs exist for the mold, which may be selected to suit the physical properties of the liquid melt and the solidification process. Molds may exist in the top, horizontal or bottom-up pouring and may be fluted or flat walled. The fluted design increases heat transfer owing to

1950-553: The noted exception of silicon, which is not a metal. Other forms include: In production engineering , metallurgy is concerned with the production of metallic components for use in consumer or engineering products. This involves production of alloys, shaping, heat treatment and surface treatment of product. The task of the metallurgist is to achieve balance between material properties, such as cost, weight , strength , toughness , hardness , corrosion , fatigue resistance and performance in temperature extremes. To achieve this goal,

2000-507: The operating environment must be carefully considered. Determining the hardness of the metal using the Rockwell, Vickers, and Brinell hardness scales is a commonly used practice that helps better understand the metal's elasticity and plasticity for different applications and production processes. In a saltwater environment, most ferrous metals and some non-ferrous alloys corrode quickly. Metals exposed to cold or cryogenic conditions may undergo

2050-482: The ore feed are broken through crushing or grinding in order to obtain particles small enough, where each particle is either mostly valuable or mostly waste. Concentrating the particles of value in a form supporting separation enables the desired metal to be removed from waste products. Mining may not be necessary, if the ore body and physical environment are conducive to leaching . Leaching dissolves minerals in an ore body and results in an enriched solution. The solution

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2100-438: The physical performance of metals. Topics studied in physical metallurgy include crystallography , material characterization , mechanical metallurgy, phase transformations , and failure mechanisms . Historically, metallurgy has predominately 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

2150-402: The piece being treated. The compression stress in the surface of the material strengthens the part and makes it more resistant to fatigue failure, stress failures, corrosion failure, and cracking. Thermal spraying techniques are another popular finishing option, and often have better high temperature properties than electroplated coatings. Thermal spraying, also known as a spray welding process,

2200-445: The process of shot peening, small round shot is blasted against the surface of the part to be finished. This process is used to prolong the product life of the part, prevent stress corrosion failures, and also prevent fatigue. The shot leaves small dimples on the surface like a peen hammer does, which cause compression stress under the dimple. As the shot media strikes the material over and over, it forms many overlapping dimples throughout

2250-464: The process. Depending on the end use, metals can be simply cast into the finished part, or cast into an intermediate form, such as an ingot , then worked, or wrought, by rolling, forging , extruding, or other deformation process. Although the same operations are used with ferrous as well as nonferrous metals and alloys, the reaction of nonferrous metals to these forming processes is often more severe. Consequently, properties may differ considerably between

2300-666: The product by a process called work hardening . Work hardening creates microscopic defects in the metal, which resist further changes of shape. Metals can be heat-treated to alter the properties of strength, ductility, toughness, hardness and resistance to corrosion. Common heat treatment processes include annealing, precipitation strengthening , quenching, and tempering: Often, mechanical and thermal treatments are combined in what are known as thermo-mechanical treatments for better properties and more efficient processing of materials. These processes are common to high-alloy special steels, superalloys and titanium alloys. Electroplating

2350-411: The solidifying melt, for alloys there may exist a "mushy" zone, which is the result of solid-liquid equilibrium regions in the alloy's phase diagram , and a liquid region. The rate of front advancement controls the time that dendrites or nuclei have to form in the solidification region. The width of the mushy zone in an alloy may be controlled by tuning the heat transfer properties of the mold or adjusting

2400-771: The success of the Philistines . Historical developments in ferrous metallurgy can be found in a wide variety of past cultures and civilizations. This includes the ancient and medieval kingdoms and empires of the Middle East and Near East , ancient Iran , ancient Egypt , ancient Nubia , and Anatolia in present-day Turkey , Ancient Nok , Carthage , the Celts , Greeks and Romans of ancient Europe , medieval Europe, ancient and medieval China , ancient and medieval India , ancient and medieval Japan , amongst others. A 16th century book by Georg Agricola , De re metallica , describes

2450-552: The third millennium BC in Palmela , Portugal, Los Millares , Spain, and Stonehenge , United Kingdom. The precise beginnings, however, have not be clearly ascertained and new discoveries are both continuous and ongoing. In approximately 1900 BC, ancient iron smelting sites existed in Tamil Nadu . In the Near East , about 3,500 BC, it was discovered that by combining copper and tin,

2500-434: 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 / m ɛ ˈ t æ l ər dʒ i / pronunciation

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