Sheet Metal Stamping Simulation

(1) A closed-die squeezing operation in which all surfaces of a workpiece are confined or restrained, resulting in a well-defined imprint of the die on the work. (2) A restriking operation used to sharpen or change an existing radius or profile. Coining can be done while forgings are hot or cold and is usually performed on surfaces parallel to the parting line of the forging.

Source: The OHIO State University

Coining is a form of precision stamping in which a workpiece is subjected to a sufficiently high stress to induce plastic flow on the surface of the material. A beneficial feature is that in some metals, the plastic flow reduces surface grains size, work hardening the surface, while the material deeper in the part retains its toughness and ductility. The term comes from the initial use of the process: manufacturing of coins. Coining is used to manufacture parts for all industries and is commonly used when high relief or very fine features are required. For example, it is used to produce money (coins), medals, badges, buttons, precision-energy springs and precision parts with small or polished surface features. Coining is a cold working process (similar to forging which takes place at elevated temperature) that uses a great deal of force to plastically deform a workpiece, so it conforms to a die. Coining can be done using a gear driven press, a mechanical press, or more commonly, a hydraulically actuated press. Coining typically requires higher tonnage presses than stamping, because the workpiece is plastically deformed and not actually cut, as in some other forms of stamping.

Source: WIkipedia