Metallurgy

Metallurgy is a domain of materials science and of materials engineering that studies the physical and chemical behavior of metallic elements and their mixtures, which are called alloys.

Production engineering of metals

Metals are shaped by processes such as casting, forging, rolling, extrusion, sintering, metalworking, machining and fabrication. With casting, molten metal is poured into a shaped mould. With forging, a red-hot billet is hammered into shape. With rolling, a billet is passed through successively narrower rollers to create a sheet. With extrusion, a hot and malleable metal is forced under pressure through a die, which shapes it before it cools. With sintering, a powdered metal is compressed into a die at high temperature. With machining, lathes, milling machines, planing machines and drills are used to cut the cold metal to shape. With fabrication, sheets of metal are cut with guillotines or gas cutters and bent into shape.

Related Topics:
Casting - Forging - Rolling - Extrusion - Sintering - Metalworking - Machining - Fabrication - Mould - Billet - Die - Powdered metal - Lathe - Milling machine - Planing machine - Drill - Guillotine - Gas cutter

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"Cold working" processes, such as rolling and fabrication, where the product’s shape is altered while the product is cold, can increase the strength of the product by a process called work hardening. Work hardening creates microscopic defects in the metal, which resist further changes of shape.

Related Topics:
Cold work - Work hardening - Microscopic defects

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Various forms of casting exist in industry and academia. These include sand casting, investment casting (also called the ?lost wax process?), permanent mold casting and continuous casting.

Related Topics:
Casting - Sand casting - Investment casting - Lost wax process - Permanent mold casting - Continuous casting

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Welding is a technique for joining certain ferrous metals and certain aluminium alloys. The metals in the weld and on both sides of the join are generally similar alloys. Brazing is a technique for joining copper-based metals.

Related Topics:
Welding - Brazing

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Metals can be heat-treated by annealing, quenching and case hardening to alter properties of toughness, hardness or resistance to corrosion. Annealing is used to make a shaped product tougher by reducing the effects of work hardening. Quenching and case hardening are used to make a shaped product harder.

Related Topics:
Heat-treated - Annealing - Quenching - Case hardening

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Electroplating is the main surface treatment technique and involves bonding a thin layer of another protective metal such as gold, silver, chromium or zinc to the surface of the product to reduce corrosion.

Related Topics:
Electroplating - Gold - Silver - Chromium - Zinc

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