Investigation of Friction and Adhesion Behavior of Textured Workpieces and Coated Tools Under Dry Tribological Contact

Processes in cold forming are accompanied by high process loads, which are reduced by means of lubricants. Lubricants are ecologically and economically questionable and increasingly restricted by legislation. In a current research project, the substitution of lubricants by coatings for tools and texturing of workpieces in a full forward extrusion process is investigated. Exact friction values of combinations of texturing and coating are necessary to investigate the process numerically and experimentally. For solid forming, the ring compression test has proven to be a valid analogy test for determining the friction factor. In this paper, the latest investigations concerning the dry tribological contact of coated and uncoated tools with different textured workpiece surfaces are shown in the ring compression test. The flow and adhesion behavior of the active partners under loads of cold forming are investigated. Furthermore, the friction factor for numerical investigations of full forward extrusion process is determined.