| 1. |
- Korin, Christer, 1970-
(författare)
-
Mechanical Behaviour of Adhesive Joints in Cartonboard for Packaging
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A cartonboard package is often sealed and closed with an adhesive – either a hot-melt adhesive (adhesives that are applied in a molten state on the cartonboard) or a dispersion adhesive (adhesives that are applied as water-based dispersions). This thesis focuses on the process of hot-melt gluing, and how material properties and process conditions affect the performance of the adhesive joint. Requirements vary depending on how the package is to be used. A package that is only supposed to protect the product during transport differs from one that is supposed to attract consumers and facilitate their use of the product. If a package has been opened, due to external or internal forces that cause a fracture in the adhesive joint, the consumer may choose another package instead. A fracture of the adhesive joint may occur in several different ways; for example, a cohesive fracture in the adhesive, an interfacial fracture between the adhesive and one of the cartonboard surfaces, and a cohesive fracture in the cartonboard. The traditional way of testing the adhesive joint is to subjectively evaluate the fibre tear after manually tearing the joint apart. The primary interest of this study has been to find an objective method that can characterise the adhesive joint – that is, its strength and joint characteristics. The work has principally concentrated on physical experiments where the Y-peel method has been evaluated and further developed, including the construction of a laboratory adhesive applicator. Adhesive joint failure is analysed and correlated to the force-elongation curve during Y-peel testing in order to explore various mechanisms of the failure. The force versus elongation curves are transformed into a force versus inelastic deformation curve for the adhesive joint. The inelastic deformation of the adhesive joint is defined as the inelastic opening of the adhesive joint perpendicular to the cartonboard surface. The dissipative descending energy has been used to characterise the adhesive joint. High descending dissipative energy showed high resistance against final failure of the joint. This correlates very well with the manual fibre-tear test. Characteristic force-elongation curves in Y-peel testing – that is, the shape of the curve – have been analysed, and four main failure modes have been identified. The finite element method has been used to predict mechanical behaviour in the ascending part of the force-elongation curve. When it comes to local behaviour, a high stiffness adhesive results in bending behaviour while a low results in shearing, but on a global scale, no big difference was detected on the ascending part of the force-elongation curve. The new laboratory adhesive applicator and finite element method can be used to objectively design the interaction between the adhesive and the cartonboard for a specific application. This can be achieved by modifying the cartonboard, the adhesive or the process parameters.
|
|
| 2. |
- Eriksson, Daniel, 1987-, et al.
(författare)
-
Damage to Carton Board Packages Subjected to Concentrated Loads
- 2014
-
Ingår i: Responsible Packaging for A Global Market. - Melbourne : Victoria University. - 9781862726994 ; , s. 172-182
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Carton board packages subjected to concentrated loads near the edges are damaged in a characteristic way. This paper reports an attempt to simulate the damage process in the lab and Package Collapse Loads measured for this load case.Packages were compressed by a concentrated load. The position of load application was varied along a line parallel to a crease and the package was rotated in order to test the influence of the height of the load carrying panel. Force and displacement were recorded and the damage evolution during the test was studied. The damage produced was examined using x-ray tomography. The nature of damage at different stages of damage evolution was studied.Both the visual appearance of the damage and the force-displacement curve were similar in all tests. The Package Collapse Load has little dependence on where along a line parallel to a crease of the package the point load is applied. Damage started developing at the crease and a yield line perpendicular to the crease and parallel to the direction of the load developed. When the displacement increased further, a parabolic yield line, symmetric around the previous one, developed. The start of the damage development was associated with at peak in the force-displacement curve. Stiffness was more geometry dependent than strength. On macro scale, the visual appearance of the damage due to concentrated loads shows no significant dependence on geometry.
|
|
| 3. |
- Eriksson, Daniel, 1987-, et al.
(författare)
-
Evaluating the use of a tactile sensor for measuring carton compliance
- 2020
-
Ingår i: Nordic Pulp & Paper Research Journal. - : Walter de Gruyter. - 0283-2631 .- 2000-0669. ; 35:3, s. 362-369
-
Tidskriftsartikel (refereegranskat)abstract
- This work reports the evaluation of a tactile sensor for the potential of using it to measure the compliance of folding cartons. A tactile sensor would make it possible to measure the mechanical behavior locally around the contact point, in contrast to existing methods that measure the global mechanical behavior of the carton. Research on the haptic sense has shown that the local mechanical behavior is more important than the global behavior when humans assess compliance of objects. It is shown that the response of the tactile sensor correlates strongly with the bending stiffness of the board, but also with geometric features. A method for reducing the 22-dimensional output of the sensor to single meaningful feature using linear discriminant analysis is proposed and tested. The results show that the sensor is a good candidate for a method that incorporates both cutaneous and kinaesthetic information in the measure of carton compliance.
|
|
| 4. |
- Eriksson, Daniel, 1987-
(författare)
-
Getting to grips with cartons : Interactions of carbonboard packages with an artificial finger
- 2021
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Packaging is an important part of most products in our modern world. It produces waste, but it also enables products to reach consumers safely and efficiently. Hence, the proper design of packaging is becoming increasingly important. Historically, cartonboard packages were designed for box compression strength. While this remains important, there are other types of loads that are important to consider. One such type of load arises from manual handling. As packages as moved and used, consumers need to exert forces on the package. These forces deform and can damage the package.Understanding these interactions can be challenging. By developing a method for quantifying the deformation due to manual handling, it becomes possible to measure and compare a redesigned package with the original to see if the performance has changed. This can aid packaging designers, but it can also be used for product control. The converting process is complex and deviations from specification can be introduced at many points along the production process.In this work, a method for quantifying interactions similar to those in manual handling is presented and evaluated. The method is then applied to study the effect of position and material properties on the mechanics of the interaction. The method is shown to have low variability and be robust to modifications in packaging and experimental design. It was seen that increasing the size of packages from 82 mm to 98 mm corresponded to decreasing the grammage by 10-20%. The method also showed the stiffening effect of corners and flaps, suggesting that the strategic placement of these design elements could help maintain the desired mechanical properties of the package at the point of interaction, provided the most likely point can be predicted.
|
|
| 5. |
- Eriksson, Daniel, 1987-, et al.
(författare)
-
How Small Is a Point Load? : A Preliminary Study of the Deformation and Failure of Cartons Subjected to Non-Uniform Loads
- 2017
-
Ingår i: Packaging technology & science. - : John Wiley & Sons. - 0894-3214 .- 1099-1522. ; 30:7, s. 309-316
-
Tidskriftsartikel (refereegranskat)abstract
- Consumer packaging made from carton board is subjected to a variety of loads as it moves through the value chain. Packaging designers need tools for predicting the strength of packages under these loading conditions. For evenly distributed loads, there are methods for measuring and estimating compression resistance that can provide useful guidance. For loads concentrated to a small area, little work has been published. The aim of this preliminary study is to aid the development of a future test method for point loads by investigating how the size of the load application site influences the mechanical behaviour of the package. Rigid spheres of a range of sizes were used to compress packages. Small spheres gave rise primary damage in the form of a vertical yield line and secondary damage in the form of a parabolic yield line. Larger spheres produced a series of parabolic yield lines of increasing size. No vertical yield line appeared for the larger spheres. The larger spheres showed a stiffness transition at a displacement that could be estimated by considering the geometry of the test.
|
|
| 6. |
- Eriksson, Daniel, 1987-, et al.
(författare)
-
Laboratory measurement method for the mechanical interaction between a tactile sensor and a cartonboard package – presentation and evaluation
- 2021
-
Ingår i: Nordic Pulp & Paper Research Journal. - : Walter de Gruyter. - 0283-2631 .- 2000-0669. ; 36:1, s. 91-99
-
Tidskriftsartikel (refereegranskat)abstract
- The importance of sensory information in product purchasing decisions has gained increasing attention in recent years. Tactile properties of packaging are usually measured with the help of trained evaluators. An objective, fast and repeatable method that describes the mechanical interaction and does not rely on a panel would have many benefits. We propose and evaluate such a method for measuring the mechanical interaction between a deformable finger-like shaped sensor and a package. Evaluation of the method shows good repeatability, the variability in the measurement result is within a few percent in most cases. The method captures indentation differences at contact between sensor and package due to measurement position and package design.
|
|
| 7. |
|
|
| 8. |
- Hallbäck, Nils, et al.
(författare)
-
Finite Element Analysis of Hot Melt Adhesive Joints in Carton Board
- 2014
-
Ingår i: Packaging technology & science. - : Wiley. - 0894-3214 .- 1099-1522. ; 27:9, s. 701-712
-
Tidskriftsartikel (refereegranskat)abstract
- The mechanical behaviour of adhesive joints is critical for the performance of adhesively joined carton board packages. In this work, finite element analyses of hot melt adhesive (HMA) joints in carton board is conducted and compared to experimental results obtained using a Y-peel testing device. The aim of the present study is to analyse the behaviour of adhesive joints tested in the Y-peel testing device using a layered carton board model. The carton board is modelled as a layered structure where the layers are assumed to obey Hill's orthotropic elastic-plastic model, and the interfaces are modelled using a softening orthotropic damage model. The HMA is modelled as isotropic linear elastic, and the influence from a varying elastic modulus of the HMA is explored. It is found that the pre-peak behaviour of the Y-peel force-elongation curves is reasonably well captured by the FE simulations, although the initial stiffness is somewhat too high. Also, the pre-peak behaviour is practically insensitive to changes of the elastic modulus of the HMA. The deformation and delamination pattern obtained in the simulations was compared with microscope pictures taken during the corresponding Y-peel experiments, and it is shown that they conform to the observed behaviour during Y-peel testing at comparable loading levels. However, the delamination opening is somewhat underestimated by the model.
|
|
| 9. |
- Korin, Christer, 1970-, et al.
(författare)
-
Analytical prediction of package collapse loads : consideration to windows in the package
- 2014
-
Ingår i: Nordic Pulp & Paper Research Journal, ISSN. - 0283-2631. ; 29:4, s. 717-724
-
Tidskriftsartikel (refereegranskat)abstract
- Windows in a package is a common way to promote the product. The possibility to predict the collapse load for these types of cartonboard packages is considered. It is shown that reliable estimates of the collapse loads can be obtained by a very simple approach. This approach is a straightforward generalization of the proposal by Ristinmaa et al. (2012): for a side that contains a window, one simply removes the strip of the package side in the loading direction that contains the window. The calculation procedure is described in detail. As a test of the calculation procedure, comparisons are made with experimentally obtained collapse loads for packages containing windows with different sizes and locations.
|
|
| 10. |
|
|
| 11. |
|
|
| 12. |
- Korin, Christer, 1970-
(författare)
-
Fracture Behaviour of adhesive Joints in carton board
- 2007
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A carton-board package is often sealed and closed with an adhesive. Package requirements vary depending on how the package is to be used. A package that is only supposed to protect the product during transport differs from one that is supposed to attract consumers and facilitate the use of the product by consumers. Fracture of the adhesive joint may occur in several different ways, e.g. cohesive fracture in the adhesive, interfacial fracture between the adhesive and one of the carton-board surfaces, and cohesive fracture in the carton board. The traditional way of testing the adhesive joint is to subjectively evaluate the fibre tear after manually tearing the joint apart. The adhesives used in carton-board packages are either hot-melt adhesives (adhesives that are applied in a molten state on the carton board) or dispersion adhesives (adhesives that are applied as water-based dispersions).The primary interest of this study has been to find an objective method that can characterise the adhesive joint, i.e. the strength and joint characteristics. The work has principally concentrated on physical experiments where the Y-peel method is evaluated and further developed, including construction of a laboratory adhesive applicator.Adhesive joint failure is analysed and correlated to the force-elongation curve in order to explore various mechanisms of adhesive-joint failure. The force versus elongation curves are transformed into a force versus inelastic deformation curve for the adhesive joint. The inelastic deformation of the adhesive joint is defined as the inelastic opening of the adhesive joint perpendicular to the carton-board surface. The dissipative descending energy has been used to evaluate the adhesive joint. High descending dissipative energy resulted in high resistance against final failure of the joint. This correlates very well with the manual fibre-tear test. Characteristic force-elongation curves in Y-peel testing, i.e. the shape of the curve, have been analysed and found to have four main failure modes.Using both the newly designed adhesive applicator and the Y-peel test method revealed a large discrepancy, about three orders of magnitude, between the theoretical thermodynamic analysis and the experimental test result. The new objective method can be used to design the interaction between the adhesive and the carton-board surface for a specific application. This can be achieved by modifying the carton board, the adhesive or the process parameters.
|
|
| 13. |
|
|
| 14. |
- Korin, Christer, 1970-, et al.
(författare)
-
Influence of surface treatments on the mechanical strength of hotmelt adhesive joints made of cartonboards
- 2012
-
Ingår i: Journal of Adhesion Science and Technology. - 0169-4243 .- 1568-5616. ; 26:20-21, s. 2339-2356
-
Tidskriftsartikel (refereegranskat)abstract
- The influence of surface treatments including pigment coating, surface sizing and calendering on the mechanical strength of hotmelt adhesive joints in pilot made cartonboards was studied. The mechanical strength of the joints was investigated using the Y-peel test device at 23 degrees C and 50% relative humidity. Some of the samples were investigated with respect to the failure mode by scanning electron microscopy. The surfaces were characterized in terms of surface roughness, surface chemical composition, and adhesion behaviour. A strong adhesive bond displayed fibre tear. In addition to fibre tear, interfacial failure, i.e., failure between the cartonboard and the adhesive, was the main reason for fracture in the bonded assembly. The most important factor controlling the integrity of adhesive joints seemed to be the real contact area. The adhesive joints showed significantly higher strength when the hotmelt adhesive was first applied onto the rougher cartonboard of the assembly and then the smoother cartonboard was pressed on the adhesive than vice versa. The surface roughness of cartonboards mainly depended on whether the surface was pigment coated or not. Calendering displayed only a minor effect. No clear influence of surface chemical composition of the cartonboards on the adhesive joint strength was found due to the fact that changes in surface chemistry in this study also led to changes in surface roughness. The strongest adhesive joint was created between two medium-rough and surface-sized cartonboards.
|
|
| 15. |
|
|
| 16. |
|
|
| 17. |
|
|
| 18. |
- Larsson, Joakim, 1989-
(författare)
-
Have you heard about wire? Monitoring of the wire drawing process
- 2024
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Wire made from metal is a fundamental component found in almost every complex product, ranging from a simple pen to a spacecraft. It is used to manufacture nails, screws, springs, rivets, cables, welding electrodes, and numerous other items that surround us daily.In an era characterized by increased environmental concerns and the pressing need for the industry to become more sustainable, process monitoring has emerged as a key instrument for strengthening the sustainability improvements of diverse industries and operations. Many industries have transitioned into the realm of Industry 4.0, entering an era of digital transformation and datadriven decision-making. However, the production of steel wire has fallen behind. The wire drawing process has been performed in a similar manner for the last century and the production machines generally lack advanced monitoring systems. To catch up, there is a great need to digitize the wire drawing process and that is the focus of this thesis, Monitoring of the wire drawing process.In this thesis several different methods to monitor the wire drawing process are developed and evaluated, resulting in a process monitoring system for the wire drawing process.
|
|
| 19. |
- Larsson, Joakim, 1989-, et al.
(författare)
-
The Influence of Nozzle Size on the Printing Process and the Mechanical Properties of FFF-Printed Parts
- 2023
-
Ingår i: Industrializing Additive Manufacturing. - : Springer. - 9783031429828 - 9783031429835 ; , s. 159-170
-
Konferensbidrag (refereegranskat)abstract
- Recent process developments in Fused Filament Fabrication (FFF), such as the possibilities to use high end polymers (for example PEEK) or to manufacture metal parts and parts reinforced with continuous fibers, have increased industrial interest. Previously, this additive manufacturing (AM) technology was mostly popular among hobbyists thanks to its low investment cost. With the increased industrial interest comes higher demands on product strength and production efficiency.The FFF process has many parameters that should be optimized to meet these tougher requirements. One of these parameters is the size of the nozzle through which the filament is extruded. Today a fairly wide range of sizes are available on the market, but most standard-sized printers come equipped with a 0.4 mm nozzle.In this study, a wide range of nozzles of different sizes have been manufactured to investigate how the nozzle size affects both the printing process and the mechanical properties of the printed parts. Tensile bars have been manufactured in polylactic acid (PLA) using 7 different nozzle sizes. The samples were investigatedby means of computer tomography (CT) and optical microscopy and subjected totensile testing.
|
|
| 20. |
- Persson, Camilla, 1976-, et al.
(författare)
-
Mechanical interaction between a cartonboard package and a tactile sensor depending on position and material
- 2022
-
Ingår i: Proceedings of 17th Fundamental Research Symposium, Cambridge, August/September 2022. - : FRC.
-
Konferensbidrag (refereegranskat)abstract
- The perception of mechanical rigidity when touching a package is important for purchasing decisions. This perception will depend both on the material and geometry of the product packaging, but also on the position where the package is grasped. Both kinaestethic (globally) and cutaneous cues (locally around the fingertip) play a role in the perception of compliance, but cutaneous cues are more important. We therefore use a tactile sensor to investigate the mechanical interaction between the tactile sensor and a cartonboard package; we study the changes depending on the measuring position and the material. Using linear discriminant analysis (LDA) on the measurement result we show that we can separate these two changes for separate analysis.
|
|
| 21. |
- Persson, Camilla, 1976-, et al.
(författare)
-
The influence of creases on carton board package behavior during point loading
- 2023
-
Ingår i: Nordic Pulp & Paper Research Journal. - : Walter de Gruyter. - 0283-2631 .- 2000-0669. ; 38:3, s. 491-499
-
Tidskriftsartikel (refereegranskat)abstract
- Carton board packages with different creases have been manufactured and loaded with point loads to see if there is a difference in point load behavior depending on crease. A carton board was creased in four different ways. The differences of the creases were judged according to appearance and residual moment. Three of the four creases showed divergent appearances. The re-sidual moment was as expected lowest for the hardest creased sample and vice versa. The packages with the different creases were loaded with a point load. The registered force - displacement curves were analyzed according to stiffness and collapse load. No statistically significant difference could be seen in the collapse load of the package or in the stiffness measured, indicating that with a standard point load measurement it was hard to distinguish a difference in packaging behavior due to creasing. In future work it might be interesting to further study the average stiffness, since a trend of higher average stiffness for lower matrix channel depth exists in the measurements, however not statistically ensured. One possibility to discern possibly existing differences in the resistance of packaging to point load due to crease differences could be to study the interaction in more detail.
|
|
| 22. |
- Ristinmaa, Matti, et al.
(författare)
-
Analytical Prediction of Package Collapse Loads : Basic considerations
- 2012
-
Ingår i: Nordic Pulp & Paper Research Journal. - 0283-2631 .- 2000-0669. ; 27:4, s. 806-813
-
Tidskriftsartikel (refereegranskat)abstract
- Calculation of Box Compression Resistance (BCR) is a challenging task and here the possibility of an engineering approach is considered. The strive has been towards obtaining a simple and general predictive tool with as few parameters as possible and still obtaining an accurate estimate of the BCR. The model proposed is based on the concept of dividing the package into panels and corner panels. With these remarkably few structural elements it is possible to obtain simple explicit formulas where the only material parameters are given by standard tests in terms of short span compression test and bending resistance. The BCR for different packages is then obtained by a simply summation of the load from the panels and corner panels. A validation against experimental data indicates that, despite its remarkably simplicity, the predictions are very accurate for a wide range of package types, package dimensions, board qualities and loading directions.
|
|
