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.
A process of cold forming metals in which the metal is shaped between two dies in such a manner as to fill the depression of both dies in relief by displacement of the material.
The pressing of a sintered compact to obtain a definite surface configuration (not to be confused with Repressing or Sizing).
Compressive metal flowing action.
The final pressing of a sintered compact to obtain a definite surface configuration, flatness, or surface finish.
A process of impressing images or characters from a die onto plain metal surfaces.
A metal forming process similar to stamping except that the metal is cold flowed in addition to being sheared.
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.