Coining (machining)

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Numismatics

Numismatic terminology

Currency Coins, Banknotes, Forgery Circulating currencies Community currencies Company scrip, LETS, Time dollars Fictional currencies

Ancient currencies Greek, Roman, Byzantine Medieval currencies Modern currencies Africa, The Americas, Europe, Asia, Oceania

Production Mint, Designers Coining, Milling, Hammering

Exonumia Credit cards, Medals, Tokens Notaphily Banknotes Scripophily Stocks, Bonds

Coining is a form of precision stamping. It differs from simple stamping in that enough pressure is used to cause plastic flow of the surface of the material. A beneficial feature is that in some materials, such as phosphor bronze, the plastic flow breaks up the surface grains, work hardening the surface, while the material deeper in the part retains its strength, toughness, ductility and flexibility.

Coining sometimes uses several dies to produce near-net shapes.

Mints use coining to produce money (coins), medals, police and fire fighter's badges, precision-energy springs and precision parts with small or polished surface features.

See also:

• Coin die

Metalworking:
Metal forming:	Coin die | Coining | Cold rolling | Die | Drawing | Electromagnetic forming | Flypress | Hot rolling | Hydraulic press | Hydroforming | Machine press | Progressive stamping | Progressive die | Punching | Punch press | Rolling | Shear | Sinking | Stamping press | Metal spinning | Swage
Metalworking topics:	Casting | CNC | Cutting tools | Drilling and threading | Fabrication | Finishing | Grinding | Jewellery | Lathe (tool) | Machining | Machine tooling | Measuring | Metalworking | Hand tools | Metallurgy | Milling | Occupations | Press tools | Smithing | Terminology | Welding