Investigating the role of infill structures on the shape memory effect of shape memory polymers in additive manufacturing
Author(s)
Choi, Jiwoo
Type
Thesis
Abstract
Additive Manufacturing (AM) enables designers and engineers to embed functions into printed objects by its unique advantages. This means a product, or component, which performed a specific purpose can be embedded into another part.
One way of embedding functions in AM is through the use of Shape Memory Polymer (SMP). SMP is the material that reacts to a stimulus and changes shape. Using smart material's unique properties, 3D printed objects can be transformed following intended programmed sequences.
Another way to embed the function into 3D printed objects is through the use of Metamaterial (also called smart structure). Metamaterial uses the smartly designed internal movement to embed function and derives unique properties from smartly designed structures.
This thesis investigates the effect of infill structure on the Shape Memory Effect (SME) of SMPs. By comparing various infill structures (e.g., infill patterns and internal void), the impact on SME was explored. Previously, several studies successfully programmed SME by altering printing parameters such as infill density or filling angles. However, only limited studies were performed with Material extrusion 3D printing technology, and correlations between SME and infill structure has not fully explained yet. Therefore, this study will primarily aim to study how infill-patterns or partial parts of infill structures change SME. Various infill structures are fabricated while maintaining the same external object geometry, to explore their impact on SME. It is shown that SME can be controlled without any requirement to change materials or external geometrical parameters. This enables us to embed various SME into objects all made from the same material.
One way of embedding functions in AM is through the use of Shape Memory Polymer (SMP). SMP is the material that reacts to a stimulus and changes shape. Using smart material's unique properties, 3D printed objects can be transformed following intended programmed sequences.
Another way to embed the function into 3D printed objects is through the use of Metamaterial (also called smart structure). Metamaterial uses the smartly designed internal movement to embed function and derives unique properties from smartly designed structures.
This thesis investigates the effect of infill structure on the Shape Memory Effect (SME) of SMPs. By comparing various infill structures (e.g., infill patterns and internal void), the impact on SME was explored. Previously, several studies successfully programmed SME by altering printing parameters such as infill density or filling angles. However, only limited studies were performed with Material extrusion 3D printing technology, and correlations between SME and infill structure has not fully explained yet. Therefore, this study will primarily aim to study how infill-patterns or partial parts of infill structures change SME. Various infill structures are fabricated while maintaining the same external object geometry, to explore their impact on SME. It is shown that SME can be controlled without any requirement to change materials or external geometrical parameters. This enables us to embed various SME into objects all made from the same material.
Version
Open Access
Date Issued
2021-07
Date Awarded
2021-11
Copyright Statement
Creative Commons Attribution NonCommercial Licence
License URL
Advisor
Myant, Connor
Wu, Billy
Publisher Department
Dyson School of Design Engineering
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)