Sharp Edge Cutting through Paperboard

The aim of this thesis is to investigate the micro mechanical damage and the failure of paperboard during sharp edge cutting. Tetra Pak is at the very forefront of the food packaging industry and in order to keep this market position, continuous improvements are of great importance. Increased understanding of paperboard behaviour is a driving factor for these improvements, since it enables more accurate simulations and further on manufacturing optimisations. This thesis is divided into two parts: Experimental testing and finite element modelling. The experiments are thoroughly evaluated by using tomography, microscopy and statistical analysis. The interesting observations made during the experiments are all clarified. Several possible modelling approaches are theoretically reviewed and a final finite element model using element deletion is implemented. The physical reasoning about the cutting phenomenon, based on the experiments, contributes to an increased understanding of which parameters that affect the cutting and also the understanding of the virtual responses. The results from the finite element modelling captures the observations and responses. This thesis constitutes a foundation from which further development should be based. Future work should include development of the testing procedure as well as the implemented finite element model.Tetra Pak is always pursuing understanding of what is really happening in their processes and by accurately simulating manufacturing scenarios, Tetra Pak can gain increased knowledge in a cheap and time efficient way. It is now high time to understand what really happens when paperboard is cut and try to capture this virtually