Investigation on water as lubricant in combination with a structured tool surface in micro metal forming

Abstract

The use of lubricants in forming processes is common because they reduce friction between the tools and workpiece during the forming process. Today, mainly mineral oils are used as conventional lubricant. In order to cut their amount in the future, the friction between tools and workpiece is investigated by using water as lubricant in this work. Therefore, the tools’ surfaces are structured with laser induced periodic surface structures (LIPSS) to make them hydrophilic and strip drawing tests are carried out at different traverse velocities to evaluate the resulting friction force. The results show that at a traverse velocity of v = 10 mm/s the maximum friction force is lowest for the structured tool with water (F = 7.0 N) in comparison with unstructured tools in combination with a conventional lubricant. Consequently, the potential of water as lubricant combined with a hydrophilic surface structure is highlighted.