Multi-material 3D inkjet printing for functional structures
using UV sintering and photopolymerisation
C.T. Davenne (TU Delft - Mechanical Engineering)
Johannes Goosen – Coach (TU Delft - Computational Design and Mechanics)
M Tichem – Mentor (TU Delft - Micro and Nano Engineering)
Andres Hunt – Graduation committee member (TU Delft - Micro and Nano Engineering)
More Info
expand_more
Other than for strictly personal use, it is not permitted to download, forward or distribute the text or part of it, without the consent of the author(s) and/or copyright holder(s), unless the work is under an open content license such as Creative Commons.
Abstract
Multi-material 3D inkjet printing has great potential for rapid prototyping and manufacturing of functional mesoscale structures when novel inks are combined into a fully integrated AM-process. This process can be faster and cheaper than conventional methods to produce functional structures. Research is conducted on a large range of potentially inkjet-printable materials to extend current possibilities with 3D inkjet printing. Material incompatibility together with strict fluid properties limit the range of multifunctional inks available for an integrated print process. This raises challenges such as printing with three or more materials, and finding inkjet printable materials that can be cured simultaneously using the same curing method. The aim of this research is to print functional structures using at least three materials consisting of a structural, support, and conductive material, requiring only one curing technique involving UV light exposure. An experimental setup of PiXDRO LP50 inkjet printers and various printhead assemblies are used to conduct experiments. Suitable off the shelf available inks are selected after a state of the art literature review. Stratasys Veroseries and Stratasys SUP706B are industry standard, compatible materials and cure using UV induced photopolymerisation. They are chosen as structural and support material, respectively. Novacentrix Metalon JSB25P and Mitsubishi NBSIJMU01 silver nanoparticle inks are chosen as conductive inks. First, multimaterial printing is set up and extended to 3D printing using the structural and support material inks only. Afterwards, conductive inks are tested for resistivity and behaviour on different substrates before integrating with the structural and support material ink into a multimaterial 3D print. Conductive nanoparticle inks show good conductivity on photopaper substrate, but not when printed on top of structural material. Several experiments are performed to document ink behaviour and optimise performance. A workflow is designed allowing the conversion of complex CAD models to inkjet printable files. Custom support material density for stronger supports can be generated using an in-house developed conversion application. Proof of concept multi-material functional structures are printed showcasing success of the proposed methodology.