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Scaling up—The high potential of additive manufacturing for the ceramics industry Figure 2. New Lithoz shareholders from left to right: Johann Oberhofer, Johannes Benedikt, Johannes Homa, and Hans J. Langer. customer requirements. By working with Wild, Lithoz also eliminated scaling-up issues with regard to possible production bottlenecks for the machine. Lithoz/Wild delivered the first production ready machine a year later, and, from that time on, the company grew. Two years later, the company achieved an important milestone by extending its ownership. Hans J. Langer, CEO and founder of EOS GmbH (Krailling, Germany)—one of the first commercially successful AM enterprises—joined the company in 2014 (Figure 2). EOS specializes in laser sintering and micro laser sintering AM. With the announcement of Langer’s participation, Homa said, “Through our partnership with Dr. Langer our work finds special recognition, Credit: Lithoz and our future growth opportunities will increase significantly.” The Lithoz management team, despite this achievement, realized that it was important to keep its feet on the ground. The team kept its focus on moderate, healthy growth of the company and did not take the usual route for high-tech start-ups via huge amounts of venture capital. Benedikt explains, "Lithoz prefers a rather conservative approach. We try to realistically estimate our sales potential and adapt our strategic product planning and development precisely to the needs of our customers." Lithoz established from the very beginning an agenda to fulfill high expectations of the ceramic industry with a clear focus on customer requirements and needs. Thus, Lithoz was inspired to earn ISO 9001:2015 certification in February 2016. LCM technology The company developed a portfolio that now ranges from machines and materials to software and applications. The LCM technology process precisely fabricates strong ceramic objects layer-by-layer (see sidebar below). A high-resolution optical system controls production of very precise and complex geometries with minimum feature sizes down to 100 μm. The outstanding properties of this process are high-resolution and isotropic microstructure and mechanical properties at the level of conventionally formed ceramics. LCM technology fabricates parts with standard compositions, such as alumina and zirconia, which are achieving material properties comparable to conventionally formed ceramics. For example, alumina parts show values of >99.4% theoretical density (>3.96 g/cm3) and four-point bending strength of 430 MPa. Zirconia components show theoretical density of 99.6% and strength of 650 MPa. Lithography-based ceramic manufacturing The building chamber of the CeraFab 7500 during exposure. Credit: Lithoz Lithoz offers a process for the additive manufacturing of high-performance ceramics that is called lithography-based ceramic manufacturing (LCM) technology. LCM technology allows production of high-performance ceramic parts with the same material properties as conventionally formed parts. LCM technology is a slurry-based process, where ceramic powder is homogenously dispersed in a photocurable monomer system and selectively polymerized through mask exposure to produce initially the green part. These green parts are basically composites of ceramic particles within a photopolymer matrix, which acts as a binder for ceramic particles. During thermal posttreatment, processors remove the organic matrix via pyrolysis, and particles densify during sintering to give the dense ceramic body. These two process steps are typically applied in conventional ceramic forming technologies. n Credit: Lithoz Schematic shows the projection system, slurry in a transparent vat, building platform, and recoater. 24 www.ceramics.org | American Ceramic Society Bulletin, Vol. 95, No.3


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