Lithography‐Based Additive Manufacturing of Cellular Ceramic Structures

Abstract

Lithography‐based additive manufacturing technology is a layered manufacturing approach where liquid photopolymerizable resins are solidified with ultraviolet, visible, or infrared light. Using a system based on digital mirror devices, photopolymers can be exposed selectively in order to build parts with defined geometries. By modifying the system with a rotating building platform, suspensions with a high solid loading of ceramic powders can be processed, despite the high viscosity of these resins. Depending on the field of application, various formulations were developed for fabricating customized ceramic parts made of alumina, tricalcium phosphate, or bioactive glasses, respectively. On the one hand the influence of the ceramic filler on the mechanical properties is characterized, on the other hand the good precision and the high surface quality of the process system is discussed. For alumina filled resins a solid loading of 50 vol% was used to obtain fully dense parts (>99% of theoretical density) with high fracture strength (biaxial strength of 516 MPa).

Monolithic 3D labs- and organs-on-chips obtained by lithography-based ceramic manufacture

“…The complete microsystem can be circumscribed by a box of 30 × 30 × 3 mm 3 (X, Y, Z, directions respectively). According to the detailed dimensions and to previous experiences [2,9,15,16], lithography-based manufacture constitutes a very adequate micro-manufacturing technology for the development of the proposed biomedical microsystem in an additive way and using ceramic materials. The materials used in the process have also proved excellent for in vitro trials with cells [9].…”

“…In addition, as the ceramic particles are separated, green parts have lower density and mechanical properties than compact alumina. The elimination of the organic components for achieving final composition and properties is carried out as described in previous research [15]. In short, the thermal variation is controlled inside a high-temperature chamber furnace from 30°C up to 400°C.…”

“…These postprocessing steps include debinding (thermal decomposition of binder) and sintering into a compact ceramic part. This technology was developed at TU Wien [13][14][15] and is industrially developed by Lithoz GmbH.…”

Effect of UV Radiation by Projectors on 3D Printing

“…A lot of different methods in this area were designed and experimentally approved by TU Wien. Experiments including ceramic powders to photopolymer solution were made using alumina [6][7][8][9], silica [6], Bioglass® [7,8] and zirconia [7,9]. Different amounts of additives were added to the photopolymer solutions, mixed and used like a build material for a different types of SL printers.…”

Preparation of medical implants by stereolithography

“…To prepare designed 3D ceramic structures, photo-crosslinkable composite resins have been developed as well [122,123]. In these resins, a ceramic powder is dispersed in a solution of acrylate-based monomers.…”