Hydrodynamic effects of macroscopic deterministic surface structures in cold forging processes

The tribological conditions between tool and workpiece are crucial for process feasibility and tool durability especially in bulk metal forming processes. Therefore, friction as one main parameter in forming needs to be adjusted sensitively. While in sheet metal forming lubricant pockets are known as an appropriate way to minimize friction forces, these reservoirs for lubricants are not state of the art in bulk metal forming. This paper describes the tribological benefit of macroscopic deterministic structured semi-finished parts in cold forging. (C) 2009 Elsevier Ltd. All rights reserved.