Forging tool

A forging tool, wherein

• the forging tool is used to forge a workpiece in a cuboidal forging space by using a first wall surface, a second wall surface adjacent to the first wall surface, a third wall surface that faces the first wall surface and is adjacent to the second wall surface, a fourth wall surface that faces the second wall surface and is adjacent to the first wall surface and the third wall surface, a fifth wall surface adjacent to the first to fourth wall surfaces, and a sixth wall surface that faces the fifth wall surface and is adjacent to the first to fourth wall surfaces, wherein
• the forging tool at least includes
• a first die that forms the first wall surface and the second wall surface, and
• a second die that forms the third wall surface and the fourth wall surface, and wherein
• the forging tool satisfies
• (a):
• the forging tool further includes, in addition to the first die and the second die, a third die that forms the sixth wall surface in a region surrounded by a contact surface when a bottom surface of the first die and a bottom surface of the second die are brought into contact with the contact surface;
• the first die forms a triangular region two sides of which are, of the fifth wall surface, a line of intersection of the first wall surface and the fifth wall surface and a line of intersection of the second wall surface and the fifth wall surface;
• the second die forms a triangular region two sides of which are, of the fifth wall surface, a line of intersection of the third wall surface and the fifth wall surface and a line of intersection of the fourth wall surface and the fifth wall surface;
• the workpiece is pressed between the fifth wall surface and the sixth wall surface;
• and the forging space is formed when the bottom surface of the first die and the bottom surface of the second die are brought into contact with the contact surface of the third die, or
• (b):
• the second die forms the fifth wall surface and the sixth wall surface;
• the first die has a first mating surface coplanar with the first wall surface and continuous with the first wall surface;
• the second die has a first facing surface that faces the first mating surface and that is brought into contact with the first mating surface;
• the second die further has a second mating surface coplanar with the third wall surface and continuous with the third wall surface;
• the first die has a second facing surface that faces the second mating surface and that is brought into contact with the second mating surface;
• the first facing surface, the second facing surface, the first mating surface, and the second mating surface are inclined relative to a plane perpendicular to a direction of a load so as to allow the second facing surface to move along the second mating surface and the first mating surface to move along the first facing surface when the load is applied to the first die and the second die in an axial direction of the forging tool;
• the workpiece is pressed between the second wall surface and the fourth wall surface;
• and the forging space is formed when a first die contact surface provided in the first die and a second die contact surface provided in the second die are brought into contact with each other.