Impact extrusion

A reverse extrusionThe process of forcing metal to flow through a die orifice in the same direction in which energy is being applied (forward extrusion); or in the reverse direction (backward extrusion), in which case the metal usually follows the contour of the punch or moving forming tool. The extrusion principle is used in many impression die forging applications.... More process in which metal is displaced backwards between a punch and a dieThe machined recess in a die that gives the forging its shape. to form a hollow part.