Tribological optimization of dry forming tools

Waste prevention and an efficient use of resources becomes more and more important in industry from both an economic and environmental point of view. Especially in forming processes such as deep drawing, lubricants are nowadays still an inevitable part to reduce the friction forces and to protect the tools against wear. Since cleaning of forming products is costly and time-expensive, a complete elimination of lubricants is desirable. Ultimately, the highest savings can be realized by a complete lubricant free deep drawing process - namely dry forming. In this paper, tribological optimization of dry forming tools for lubricant-free forming by means of a protective coating and micro-structuring of the tool is presented. While focusing on the improvement of frictional and wear properties, it is shown that ta-C coated tools operated in a dry environment can reduce friction up to 15% compared to the lubricated case. Moreover, it is outlined that a micro-structuring of the tool by Direct Laser Interference Patterning technology can significantly reduce the tools wear.