C02 - Versatile joining with a fastener

Due to economic and ecological requirements and the associated trend towards lightweight construction, mechanical pre-hole-free joining technologies are becoming increasingly important. New methods and processes for the production of versatile and customised joints are essential due to the increasing use of high-strength and
ultra-high-strength materials as well as an increasing number of variants. The limited possibilities for reacting to these changes require new strategies to be developed in order to increase the versatility of mechanical joining technology with adaptive tools, auxiliary joining parts and process kinematics. The aim of the sub-project is therefore to increase the versatility of the self-pierce riveting process by means of universal auxiliary joining elements and in-situ process control. Hereby both process-side disturbance variable and process parameter fluctuations as well as unscheduled changes in the boundary conditions lose their significance. To achieve this, two solution strategies are being pursued that complement each other synergistically. The approach concerns the description of an adaptive, linear process control in order to analyse the mutability of the auxiliary joining part with regard to additional intervention possibilities as well as the process-safe production of a customised joint by forming and inserting self-pierce rivet elements through a tumbling process. Parallel to the analysis of the tumbling process, a disturbance and process variable analysis within a conventional self-pierce riveting process is carried out in order to identify internal and external influencing factors. In addition, effects on the joining quality with regard to the possible load bearing capacity can be analysed. The development of the
self-pierce riveting joining part represents a further approach to increasing versatility, which is based on a geometric, material and functional adaptation of the auxiliary joining parts. In this context, the simulation of the joining process represents an important part of the development process and supports the derivation of an in-depth understanding of the process, which in turn supports the selection of suitable rivet element variants. Finally, adaptive tools are to be conceptually developed that are based on driven active elements and allow individual adaptation of the tool configuration to the joining point.