This work resulted in a simulation platform and a validated numerical framework, which can precisely model the packaging material that are made of complex paperboard composite laminates and predict the material behaviour when it undergo es processing and converting procedures.
Due to their specific advantages such as flexibility, hygiene, cost-effectiveness and environmental compatibility, paperboard composite materials are widely us ed for food and beverage packaging. The packaging materials are made of multi-layer sandwich laminates and mainly consists of several carton plies, a thin aluminium foil and several polyethylene layers. Compared to other conventional composite structures, such as carbon fibre composites, carton-based packages have an extremely thin composite structure with significantly softer material properties.
To obtain a robust and well-formed commercial packaging, many manufacturing processes are usually carried out, for instance creasing, folding or bottom and gable sealing. In addition to the structural and architectural aspects, various technical requirements must b e met regarding functionality, rigidity and robustness of the packaging. During the converting procedures; especially at higher production speeds, unexpected operational flaws might b e observed often for material rupture and inter-layer delamination influencing the quality of a package performance.
Furthermore, to examine the new paperboard material generations and operational developments, it is necessary to characterize and predict materials behaviour and packaging process if higher converting speeds, extended performance and efficiency are demanded. To satisfy the above-mentioned technical requirements, mathematical modelling and simulation methods are an appropriated way to formulate the paperboard material characteristics and analyse converting processes such as creasing and folding.
A series of quasi-static and high-speed tensile tests were carried out to determine the mechanical properties of the highly anisotropic carton material. In addition to the classical tensile test, improved tests were also conducted specifically to measure the shear strength of the paperboard plies. Tests such as the Rigid Block Shear Test (RST) and the Double Notches Shear Test (DNST) were performed to obtain the shear stress curve and maximum shear strength across the paperboard thickness, respectively. Furthermore, the z-directional tensile test (ZDT) was also employed to identify the paperboard interfacial characteristics in terms of traction-separation curves.
A mathematical model based on the finite element method (FEM) has been develop ed and implemented in the commercial ABAQUS software to simulate material behaviour under highly dynamic loads. The simulation model includes both constitutive elasticplastic formulation of packaging composite structure and a description of interlayer interaction and delamination between the composite plies as well. A formulation according to the Hill ´criteria has been used to formulate the anisotropic elastic-plastic behaviour of the material based on its rate-dependent characteristics. The interaction between the paperboard layers and the corresponding delamination during the creasing and folding processes have been implemented using an anisotropic traction separation model in respect to the relative sliding and opening of the adjacent interfaces.
The most important simulation parameters have been comprehensively investigated and optimized regarding the calculation accuracy, simulation costs and efficiency. Subsequently, the obtained numerical results were successfully validated with available experimental data for practical static and dynamic creasing and folding processes.:1. Introduction
2. The State of the Art
2.1 Introduction
2.2 Paperboard and packaging composites manufacturing process
2.3 Paperboard converting process: creasing and folding
2.4 Analyzing of existing models for packaging materials and packaging procedures
2.5 Conclusions
3 Objective and Research Program
3.1 Objective
3.2 Research Program
4 Continuum Mechanics and Modeling of Packaging Process
4.1 Introduction
4.2 Continuum mechanics
4.2.1 Deformation gradient
4.2.2 Finite strain equations
4.2.3 Constitutive model and stress decomposition
4.2.4 Velocity gradient and rate of deformation
4.2.5 Yield criteria
4.2.6 Hardening law and plastic flow 0
4.3 Analytical model for paperboard material characterization
4.3.1 Constitutive equations
4.3.2 Elasticity
4.3.3 In-plane plasticity
4.3.4 Out-of-plane plasticity
4.4 Contact and interfacial formulation
4.4.1 Normal contact analysis
4.4.2 Tangential contact analysis
4.4.3 Interface model
4.5 Conclusions
5 Development of Experimental Methods for Paperboard Material Identification
5.1 Introduction
5.2 Quasi-static tensile test
5.3 Shear and interfacial experiments
5.3.1 Rigid block shear test (RST)
5.3.2 Double notched shear test (DNST)
5.3.3 Z-directional tensile test (ZDT)
5.4 Paperboard dynamic material characterizations
5.4.1 Dynamic test set-up and measurement
5.4.2 Dynamic material calibration and parameter identification
5.5 Conclusions
6 Paperboard Composites Converting Process Experiments and Finite Element
Modeling
6.1 Introduction
6.2 Material and interfacial numerical modeling
6.3 Punching creasing
6.3.1 Punching creasing experiment
6.3.2 Punching creasing FE simulation
6.4 Dynamic creasing
6.4.1 Dynamic creasing experiments
6.4.2 Dynamic creasing simulation
6.5 Folding model
6.5.1 Folding experiment
6.5.2 Folding simulation
6.6 Conclusions
7 Results and Discussion
7.1 Introduction
7.2 FE results and validation
7.2.1 Quasi-static punching creasing process
7.2.2 High speed rotating dynamic creasing process
7.2.3 High speed folding process
7.3 Conclusions
8 Potential Analysis of Material and Process Optimization
8.1 Introduction
8.2 Material optimization
8.2.1 Material continuum characterization
8.2.2 Material interface characterization
8.2.3 Material shear characterization
8.3 Conclusion
9 Summary and Outlook
Identifer | oai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:36880 |
Date | 30 December 2019 |
Creators | Nazarinezhad Giashi, Abolhasan |
Contributors | Cherif, Chokri, Majschak, Jens-Peter, Technische Universität Dresden |
Publisher | SIG Combibloc System GmbH |
Source Sets | Hochschulschriftenserver (HSSS) der SLUB Dresden |
Language | English |
Detected Language | English |
Type | doc-type:doctoralThesis, info:eu-repo/semantics/doctoralThesis, doc-type:Text |
Rights | info:eu-repo/semantics/openAccess |
Page generated in 0.0033 seconds