Tearing Fracture & Microscopic Analysis of Laminate- Towards Sustainable Packaging

Abstract: This thesis takes an insight look into tearing behaviour of thin materials used in food packaging. The investigation was based on 2-leg trousers-tear specimen with constant pre-crack length. The materials used in this work were al-foil and a laminate composed of paperboard, low-density polyethylene and al-foil. Theory of Essential work, experimental and finite element methods were used for analysis. Microscopic study was performed to analyse the crack behaviour for both materials and comparison was made. Microscopic photographs show the actual condition of the crack; these photographs were put together with corresponding experimental data. It provided an effective method to analyse the fluctuations in the data compared with actual crack condition. A simple finite element model was made in order to show the stress distribution around the crack tip. It was found that the tearing behaviour is a combination of mode I and mode III fracture. Commercial software ABAQUS was used for finite element modelling. Crack propagation was not considered during simulation