Heavy use metal parts are often milled/shaped into a blank, then forged.
Forging involves heating the part, then hammering it into shape using specialized jigs (reverse imprint of the part). Most metals have a grain structure, similar to wood. The combination of heat and pressure bends the metal's grain structure around the contours of the part. This imparts a tremendous amount of strength compared to milling or casting. Since milling generally cuts into the grain at arbitrary angles, while casting often creates a disorganized grain structure (there are newer casting techniques which give better results).
The parts are often milled again, to ensure exact dimensions. Then finish/treatments are applied.
Heavy use metal parts are often milled/shaped into a blank, then forged.
Forging involves heating the part, then hammering it into shape using specialized jigs (reverse imprint of the part). Most metals have a grain structure, similar to wood. The combination of heat and pressure bends the metal's grain structure around the contours of the part. This imparts a tremendous amount of strength compared to milling or casting. Since milling generally cuts into the grain at arbitrary angles, while casting often creates a disorganized grain structure (there are newer casting techniques which give better results).
The parts are often milled again, to ensure exact dimensions. Then finish/treatments are applied.