Tribological size effects in forming processes

The general trend of miniaturization affects many technological fields. One of these fields is to produce micro components out of metal instead of the often used plastic materials. BIAS has been researching micro metal forming technologies for over five years. Within the priority program “Process scaling”, the tribological size effects in forming processes have been investigated. Such basic effects were identified in strip drawing and cup deep drawing.

For the investigation of the scaling effects, experiments and simulations have been carried out. As a basis for the simulation, an algorithm for the calculation of the friction coefficient against contact pressure has been developed. This makes it possible to evaluate the friction coefficient on each position in the whole process just from the machine data punch stroke and punch force.

The know-how acquired in these investigations contributes to optimizing the forming process for parts with a complex geometry, for instance rectangular parts. Based on these experiences the forming behaviour and wear behaviour of materials as well as other essential challenges of micro forming will be investigated in the Collaborative Research Centre “Micro cold forming” (www.sfb747.uni-bremen.de).

BIAS Bremer Institut für Angewandte Strahltechnik
info@bias.de
www.bias.de