The use of mechanical joining technology offers the possibility of joining mixed structures with a wide range of requirement profiles and material-geometry combinations. Due to the processes being only partially visible from the outside, the high number of combinable tool variants, and variable force- and displacement-based process parameters, it is not possible to holistically verify the joinability in adaptable process chains along the process steps using a conventional, experimental approach.

The vision of the subproject is therefore to develop methods for the holistic prediction of joining reliability, joining suitability, and joining feasibility along the adaptable process chain. In order to achieve the necessary holistic approach with regard to joining materials, joining processes, and operating conditions, subproject A01 integrates methods already developed by other subprojects of the TRR in addition to developing new methods. Combined methods consisting of experimental testing methods and simulation models that describe the joining behavior based on material behavior are being developed in order to identify fundamental principles of action and enable comprehensive prediction based on simulation. The methods will ultimately be used to develop targeted flexibility and robustness measures for adaptable process chains in response to varying input variables.

In TP A01, a simulation strategy is being developed that virtually maps the process steps of joining part production, joining process, and loading phase and allows the transfer of relevant state variables, such as geometry, material hardening, and damage, for a continuous simulation of mechanical joinability. The simulation model will be used in an iterative process to investigate the utility value and sensitivity of the transferred state variables with regard to the overall process and the subsequent process steps. To validate the simulation models, the entire process chain will be traced in detail experimentally, with the geometry and material state after each process step and the process variables being determined as locally as possible. This requires the development of new test methods for characterizing the friction properties and damage behavior of joining materials under the complex boundary conditions of the process chain. In addition, suitable sample shapes must be developed that can pass through the entire process chain and enable targeted adjustment of the material state during joining part production in the joining zone as well as combined load conditions.