Robocasting of complex structural ceramics
File(s)
Author(s)
Cai, Qiaosong
Type
Thesis or dissertation
Abstract
Additive manufacturing (AM) has been recognized as a significant manufacturing method since it was developed in early 1980s. It is a technology usually based on 3D model files (CAD model) and layer by layer fabrication. Many AM technologies have been developed for manufacturing different range of materials such as metals and polymers while only a few of them are suitable for producing ceramic objects.
Robocasting (also called direct ink writing) is a ceramic AM technology which was developed to produce complex ceramic parts. The technology is based on extrusion of a paste that has to exhibit a shear thinning behaviour. However, one of the remaining challenges is the fabrication of parts with complex hierarchical structures or combining different materials.
In this thesis, porous ceramics with porosity from 10 % to 60 % and average pore size from 3 μm to 8 μm were produced by robocasting emulsion-based inks. Ceramic matrix composites with continuous steel fibres were fabricated successfully by extruding filaments with a novel core/shell structure. The composites reinforced with the steel fibres have an increasing of toughness without sacrificing the strength of the products. Density, strength and toughness of the products were measured to analyse their reliability.
Robocasting (also called direct ink writing) is a ceramic AM technology which was developed to produce complex ceramic parts. The technology is based on extrusion of a paste that has to exhibit a shear thinning behaviour. However, one of the remaining challenges is the fabrication of parts with complex hierarchical structures or combining different materials.
In this thesis, porous ceramics with porosity from 10 % to 60 % and average pore size from 3 μm to 8 μm were produced by robocasting emulsion-based inks. Ceramic matrix composites with continuous steel fibres were fabricated successfully by extruding filaments with a novel core/shell structure. The composites reinforced with the steel fibres have an increasing of toughness without sacrificing the strength of the products. Density, strength and toughness of the products were measured to analyse their reliability.
Version
Open Access
Date Issued
2020-10
Online Publication Date
2021-01-29T11:37:46Z
Date Awarded
2020-12
Copyright Statement
Creative Commons Attribution NonCommercial Licence
Advisor
Saiz Gutierrez, Eduardo
Vandeperre, Luc
Guiliani, Finn
Sponsor
Imperial College London
Publisher Department
Materials
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)