Master Thesis - Modelling delamination and bond fracture in paperboard

Extended Finite Element Method for modelling delamination and bond fracture in paperboard

More than half of global consumers are looking for packaging that aligns with recyclability, climate friendliness, and a minimal environmental footprint. Given the substantial demand, there is a pressing need to delve into the development of the 'package of the future'—one that facilitates a low-carbon circular economy while upholding stringent food safety standards. What characteristics define this future sustainable package, and more crucially, what materials constitute it? Tetra Pak® is committed to advancing the proportion of renewable materials, particularly wood fiber, in carton packages toward the ambitious target of 100%. A noteworthy example of an eco-friendly packaging solution involves the production of straws, barrier materials, and opening devices using fiber-based materials.

Simulations are today an important tool at Tetra Pak for evaluating feasibility of various designs. Accurate models of the paperboard material are needed to obtain reliable results in Finite Element Simulations and thereby enable optimization of tools and packaging material structures. During Tetra Pak’s industrial processes, the packaging material folds and delamination, e.g. separation of fiber-layers, occurs in the paperboard. Models that can predict the delamination behaviour is therefore of importance to obtain an accurate deformation response of paperboard. In addition, the inherent inhomogeneity and stochastic nature of plant and wood-based fibers, which form cellulose materials, significantly impact their mechanical performance. How the bond-strength between the individual fibers impacts the macroscopic delamination response needs to be better understood.

The goal of this project is to utilize the X-FEM technology (e.g. available in commercial softwares such as Abaqus) to model the out-of-plane behaviour of paperboard. The focus in this project is to explore the X-FEM technique and attempt to replicate the macroscopic response in out-of-plane tension and shearing of paperboard. 

Scope: 

• Literature survey on the Extended Finite Element method and the out-of-plane behavior of paperboard.
• Utilizing X-FEM for modelling the out-of-plane behaviour of paperboard.
• Establish simple fiber-network geometries where X-FEM can be applied.

Supervisors
Eric Borgqvist, eric.borgqvist@tetrapak.com, +46 733 36 35 15, Tetra Pak®
Eskil Andreasson, eskil.andreasson@tetrapak.com, +46 733 36 32 69, Tetra Pak®
Matti Ristinmaa, matti.ristinmaa@solid.lth.se, +46 46 222 79 87, LTH

Apply today as the selection will be continuous!