Three‐dimensional complex construct fabrication of illite by digital light processing‐based additive manufacturing technology

Abstract

Illite is a group of clay minerals that are expected to be widely used in catalyst fabrication, radioactive element adsorption, and so forth, due to its excellent adsorption properties. However, the shape control limitation of the illite product should be overcome to maximize its utilization and properties. We herein propose additive manufacturing (AM) as one of the best solutions to solve this structural drawback. Digital light processing (DLP) technology with the film‐type of the material supplying system was adapted instead of the general vat‐type DLP system to increase illite printability. The photo‐curability and printability of illite‐contained photocurable suspension were optimized. The color effect due to different ferric oxide content in yellow‐ and white‐illite which influence the photopolymerization process also adjusted thoroughly. White illite showed better photo‐curability and could be increased solid loading than yellow illite. The defect‐free illite products with three‐dimensional complex structures, which cannot be produced by typical ceramic processes, were obtained by DLP technology for both yellow‐ and white‐illite after sintering at 1100°C. The overcoming of shape control limitation of illites by ceramic AM proved in this study has excellent potential for expanding illite utilities in various applications.

Characterization and Mechanical Properties of Sintered Clay Minerals

“…In order to compare the CSP approach with clays, a reference study was first carried out on the conventional sintering of kaolinite, illite and natural clay material so that the success of the samples produced with CSP could be evaluated later. Kaolinite and illite are common clay minerals found in nature and used for various applications (Gianni et al, 2020, Zhang et al, 2022. Kaolinite is of particular interest as it undergoes dehydroxylation to an amorphous state (forming metakaolin), which is stable over a wide temperature range (Michot et al, 2008).…”

Fabrication of Complex Three-Dimensional Structures of Mica through Digital Light Processing-Based Additive Manufacturing

“…Using a 3D ceramic printing system that was created in-house, the ceramic pieces were manufactured using a UV light source with a wavelength of 405 nm. More information about the printing system is provided in our previous work [14]. For all builds, the layer thickness was set to 20 µm, and the UV light energy was adjusted to 10 mW/cm 2 .…”

“…While the curability and printing accuracy of the slurry are affected by factors such as the color of the powder, the composition of the resin, and the light absorption of the slurry [13]. In our previous study, we explored the possibility of DLP printing with the natural mineral illite, focusing on the influence of the natural mineral's deep color on its slurry photocuring ability [14]. Mica fabrication using DLP-based AM has not yet been reported, possibly because mica is a naturally occurring material with a large particle size that makes preparing the required slurry difficult [15].…”