Lauri Hoffmann, Bruno Gallace, Clara Herr, Kai Scherer, Adrian Huwer, Percy Kampeis, Roland Ulber, Michael Wahl

• Due to a lack of investigated materials for the additive manufacturing of multi-use functional parts in bioprocess engineering, this study aimed to evaluate the influence of multiple autoclaving cycles on the properties of a heat-resistant material (xPeek147) printed with vat photopolymerization. Sample bodies were tested regarding their mechanical properties of tensile strength, elongation at break, and Charpy impact, as well as surface properties of roughness and wettability after up to 50 autoclaving cycles (121 °C, 2 bars, 15 min). The tightness was checked after up to 20 cycles, and accuracy was inspected for manufactured benchmark bodies after up to 10 autoclaving cycles. The reported results showed no significant changes in tensile strength, elongation at break and Charpy impact after 20 cycles, but a significant decrease after 50 autoclaving cycles, accompanied by microcracks in the structure. Regarding the surface properties the material retained its hydrophilicity, and the surface roughness was not affected significantly. No changes in tightness occurred, and the benchmark bodies for dimensional changes showed no process-relevant deviations. Through the investigations, a material for the additive manufacturing of multi-use functional parts for bioprocess engineering was identified. Additionally, a testing method for materials with the same intended application was provided.