Effects of the Layer Height and Exposure Energy on the Lateral Resolution of Zirconia Parts Printed by Lithography-Based Additive Manufacturing

Abstract

Lithography-based ceramics manufacturing (LCM) processes enable the sophisticated 3 dimensional (3D) shaping of ceramics by additive manufacturing (AM). The build-up occurs, like many other AM processes, layer by layer, and is initiated by light. The built-in digital mirror device (DMD) enables the specific exposure of desired pixels for every layer, giving as a consequence a first estimation of the printing resolution in the x and y axes. In this work, a commercial zirconia slurry and the CeraFab 7500, both from Lithoz GmbH (Vienna, Austria), were used to investigate the potential of reaching this resolution. The results showed that the precision of a part is strongly dependent on the applied exposure energy. Higher exposure energies resulted in oversized dimensions of a part, whereas too low energy was not able to guarantee the formation of a stable part. Furthermore, the investigation of the layer thickness showed that the applied exposure energy (mJ/cm2) was acting in a volume, and the impact is visible in x, y, and z dimensions. The lowest applied exposure energy was 83 mJ/cm2 and showed the most accurate results for a layer thickness of 25 μm. With this energy, holes and gaps smaller than 500 μm could be printed; however, the measurements differed significantly from the dimensions defined in the design. Holes and gaps larger than 500 μm showed deviations smaller than 50 μm from the design and could be printed reliably. The thinnest printable gaps were between 100 and 200 μm. Concerning the wall thickness, the experiments were conducted to a height of 1 cm. Taking into account the stability and deformation of the walls as well, the best results after sintering were achieved with thicknesses of 200–300 μm.

Additive Manufacturing of Electrochemical Energy Storage Systems Electrodes

“…However, postprocessing is essential to fully densify the printed components, including the removal of the bonding materials (or debonding) and sintering. [36] Polymer binders can be removed via thermodecomposition, but some polymers (preceramic polymers) may also convert to ceramics, or polymer-derived ceramics (PDCs). [36][37][38] Compared with direct AMTs for these solid materials, such as selective laser sintering (SLS) or selective laser melting (SLM), indirect techniques increase the quality (accuracy or smoothness) in bulk and surface of the parts.…”

“…[36][37][38] Compared with direct AMTs for these solid materials, such as selective laser sintering (SLS) or selective laser melting (SLM), indirect techniques increase the quality (accuracy or smoothness) in bulk and surface of the parts. [36]…”

Optimized Zirconia 3D Printing Using Digital Light Processing with Continuous Film Supply and a Recyclable Slurry System

“…The layer thickness was kept at 50 µm for this research. Exposure energy of 20.76 mJ/cm 2 was applied to print each layer except for the first five layers, where 62.28 mJ/cm 2 was applied [31,32]. Other parameters used are mentioned in Table 1.…”

3D-Printed Hermetic Alumina Housings

“…By slurry-based technologies like Vat Polymerization or Inkjet Printing, very fine detailed structures can be realized but the devices are very expensive. Due to crosslinked photopolymers, Vat Polymerization needs very long debinding times [ 11 ], but it reaches relative densities > 99% [ 12 ]. For Inkjet Printing due to small nozzle sizes, submicron powders are essentially [ 6 ].…”