In the realm of lithography-based metal manufacturing (LMM), Incus GmbH and Element22 GmbH have achieved a significant milestone by demonstrating the production of personalized Smart Watch Housings made from Titanium6Al4V (Ti64). The parts were printed by Incus, sintered and finished by Element22. Recognizing the challenges of processing Ti64 in binder- or sinter-based additive manufacturing (AM) processes, Incus and Element22 collaborated on a joint R&D project.
The developed feedstock or printing material consists of the binder and Metal Injection Molding (MIM) grade Ti64 powder at 55Vol% solids loading. The binder undergoes photopolymerization during irradiation with light, forming a green part layer-by-layer. The green strength of LMM printed parts, typically around 13MPa in a 3-point-bending setup, exceeds other sinter-based AM processes, enabling automated handling during extraction or de-powdering, and placement of the printed green parts onto the sintering setter.
During debinding and sintering, the binder is thermally decomposed, leaving behind only the metal powder. A solids loading of 50Vol%+ is typically needed to achieve dense and mechanically functional parts, which sinters to the final solid materials with theoretical densities exceeding 99%. The LMM process yields a surface finish down to 2µm Ra (as-sintered) and a resolution of 35µm.
This initiative of Incus and Element22 resulted in a low-carbon photopolymer-based binder system and an adapted thermal processing route for Ti64. The resulting Ti64 exhibits exceptional mechanical properties, surpassing ASTM F2885-17 standards for medical implant applications. Ti64 stands out for its high tensile strength, corrosion resistance, and biocompatibility. Its favorable strength-to-weight ratio makes it an ideal material for diverse high-performance applications in aerospace, defense, automotive, oil and gas, medical devices, and high-end consumer goods.
In this specific application, Element22 and Incus successfully manufactured a Ti64 Smart Watch Housing, finished (sand blasted) and colored, ready to be adopted in a personalized smart device. Beyond the advantages of mass customization, LMM excels in achieving MIM-like quality parts within hours, rather than weeks. Matthias Scharvogel, CEO of Element22, emphasizes the benefits of LMM in this context, stating, “Being a user of LMM, we can achieve significant savings in time to market for our customers, especially for high-quality prototypes and mass customization.”
Incus’s new HammerPro40 mass production unit further reduces production costs. With the capability to print up to 16 watch cases in less than 2.5 hours, the annual production capacity can reach approximately 35,000 pieces. Gerald Mitteramskogler, CEO of Incus, asserts, “The HammerPro40 demonstrates our ability to match or even surpass the production economics of classical milling centers. Our LMM technology has proven its ability to match intended size and function without the need for extensive surface finishing or machining.”
Mitteramskogler underscores the value of LMM, stating, “With a fully customized smartwatch housing, we can achieve a competitive cost structure compared to traditional manufacturing technologies, especially when designs can no longer be realized with MIM or CNC.”
These developments signal an adoption of LMM to high-volume applications and aid in accelerating the adoption of additive manufacturing for the serial and mass production of highly customized consumer goods.