Mechanical Considerations in Forged Shaft Design

Forged shaft design requires a comprehensive consideration of mechanical properties and manufacturability. In terms of material selection, carbon steel (such as 45 steel) is low in cost and easy to process, while alloy steel (such as 40Cr) is suitable for high-load scenarios. Structural design needs to avoid stress concentration by using fillet transitions and reasonable shoulder heights, and fatigue strength can be improved through heat treatments such as quenching and tempering, and carburizing. In terms of manufacturing processes, hot forging can refine grain size, while cold forging can improve surface finish, but the deformation force and die wear need to be balanced.