Additive Manufacturing (AM) is a class of echnologies whereby components are made in an additive, layer-by-layer fashion enabling production of complex parts in which complexity has little or no effect on cost. However typical components roduced using these techniques are basic structural items with no major strength requirement and low geometric tolerances made from a single material. his thesis develops a low-cost Fused Filament abrication (FFF) based AM technique to produce functional parts. This is achieved by through esearching and implementing new materials in ombination and using precise control of infill tool paths for existing materials. Robocasting has previously been shown to be extremely versatile, however is known to offer poorer build quality relative to its ess-versatile counterparts. Research was ndertaken to enable Robocasting to be combined with FFF to enable the print quality and practical benefits of FFF with the material flexibility of Robocasting. This resulted in the manufacture of several multiple-material omponents using the technique to demonstrate its potential.In order to minimise the number of materials required to obtain desired properties, the effect of process parameters such as layer height, infill angle, and infill porosity were investigated. In total over an order of agnitude variation in Young’s modulus and tensile strength were achieved, enabling these properties to be actively controlled within the manufactured components.Finally a novel non-eutectic low melting point alloy was developed to be compatible with the FFF process. Its greater viscosity compared to traditional eutectics resulted in improved print quality and the reliable deposition of electrically conductive track 0.57x0.25mm in cross-section. In addition the material is approximately three orders of magnitude more conductive that typical printable organic inks. A micro-controller was produced using the technique in conjunction with traditional electronics components. This represents the first time a functional electrical circuitry, with sufficient conductivity for the majority of applications and interfacing directly with standard electrical components, has been produced using a very low-cost AM technique such as FFF.The research undertaken builds components with substantially improved functionality relative to traditional AM products, enabling electromechanical components with varying mechanical and electrical properties. It is anticipated that this could substantially reduce the part-count for many engineering assemblies and open up Additive Manufacturing to many new applications.
|Date of Award||2 Jul 2013|
|Supervisor||Adrian Bowyer (Supervisor) & Pejman Iravani (Supervisor)|
- additive manufacturing