Hybrid Fabrication of Zirconia Parts with Smooth Surface Texture and Tight Tolerances

• Published in: Journal of composites science Vol. 8; no. 7; p. 233
• Main Authors: Spitaels, Laurent, Dambly, Valentin, Beobide Otaegi, Aiora, Bossu, Julien, Delmotte, Cathy, Martic, Gregory, Juste, Enrique, Carrus, Raoul, Arrazola, Pedro-José, Petit, Fabrice, Rivière-Lorphèvre, Edouard, Ducobu, François
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01.07.2024
• Subjects: Additive manufacturing; Ceramic molds; Ceramics; Energy consumption; Finishing; geometrical tolerances; hybrid; Injection molding; Manufacturing; material extrusion; milling; Milling (machining); Raw materials; Sintering; Supply chains; Surface layers; surface texture; Tolerances; zirconia; Zirconium dioxide
• ISSN: 2504-477X; 2504-477X
• DOI: 10.3390/jcs8070233

The conventional manufacturing chain for technical ceramics is too expensive for the production of small series or unique parts with complex designs. Hybrid machines that combine additive and subtractive processes can be an interesting solution to overcome this technology lock-in. However, despite the great interest in hybrid machines for metallic parts, there is a lack of data in the literature when it comes to ceramics. The purpose of this paper is to contribute to closing this gap. It is the first to evaluate the achievable geometrical tolerances according to ISO 2768-2 as well as the surface textures of composite zirconia parts shaped sequentially by pellet additive manufacturing (PAM, from ceramic injection molding feedstock) and finish milling. The green parts were then debinded and sintered to analyze the influence of these steps. Compared to the initial green parts, the sintered parts exhibited shiny and smooth surfaces with sharp edges. Flatness, parallelism and perpendicularity all achieved an H (fine) class, while the surface textures were significantly improved, resulting in arithmetic roughness (Ra) below 1.6 µm.