Tailoring 3D printed Ceramics via Two-Photon-Polymerization and Lithography-based Ceramic Manufacturing
SÄNGER J. 1,2, HOFER A. 1, SCHLACHER J. 1, GÜNSTER J. 2,3, BERMEJO R. 1
1 Montanuniversity Leoben, Leoben, Austria; 2 Federal Institute for Materials Research and Testing (BAM), Berlin, Germany; 3 Clausthal University of Technology, Clausthal-Zellerfeld, Germany
Vat-Polymerization techniques promise the highest accuracy of all additive manufacturing technologies. This also applies for ceramic-AM, where the most detailed ceramic structures can be achieved at different length scales. In this work, the possibilities of using Two-Photon-Polymerization (2PP) and Lithography-based Ceramic Manufacturing (LCM) techniques are explored. Both techniques work on the same chemical principle but require different optical properties. The material requirements for these two different technologies are discussed, with special focus on the resin selection.
In the case of 2PP, Yttria stabilized Zirconia (YSZ) nanoparticles were successfully utilized in high weight fractions of up to 85wt% at excellent transmittance of ca. 90%. It enables the production of technical ceramics with an accuracy of 500nm and with remarkable structural properties forming a ceramic meta material. In order to fabricate parts in larger specimen size additional technologies faster than 2PP such as LCM are required, which combine good accuracy with small printing time and reasonable object size. The versatility of this technique in fabricating ceramics with tailored microstructure and properties is demonstrated in two study cases: (i) Multilayer design of alumina and alumina-zirconia materials manufactured using the 2K-(LCM) technology, reaching a biaxial strength of 1GPa, associated with the residual stresses upon cooling down from sintering, in comparison to 650 MPa on 3D-printed bulk alumina. (ii) Textured alumina microstructure combining alignment of high aspect ratio templates with Templated Grain Growth method, to reach biaxial strength of 670 MPa, compared to 570 MPa measured on equiaxed alumina sintered. The possibility of combining both LCM and 2PP techniques for 3D printed parts is discussed.