Simulation of forming of paperboard packaging using LS-DYNA

Paperboard is widely used as a package material for food and beverage. The ability to simulate the forming of the packages is of great interest, due to the variety in shapes and paperboard material structure combined with production speed. The main task when producing a paperboard package is that the structural integrity of the container is not compromised through e.g. in-plane surface cracks of the paperboard. This may lead to leakage which will jeopardize the integrity of the container. As a material, paperboard is highly anisotropic due to the composition and alignment of fibers. Also, the stacking of fibers into planes introduces a vast difference in out of plane and in plane properties. To accommodate for this, a material model denoted *MAT_PAPER has been implemented into LS-DYNA based on the work done by Xia, Nygårds and Borgqvist. The forming of a paperboard package includes a creasing stage where the material is delaminated locally to achieve a nice fold pattern without causing in-plane surface cracks. The paperboard is then folded and subsequently filled. This paper will present the current status and novel features of *MAT_PAPER in LS-DYNA. Also, a brief overview of the different types of simulations that are required for modeling of package forming will be discussed based on modeling technique and expected results.