Materials manufacturer Covestro is introducing Somos WaterShed AF, a new stereolithography resin that simplifies 3D printing investment casting patterns. Designed to address sensitivities in the casting of certain specialty alloys, the resin results in clean burnout with low residual ash, positively impacting the overall process efficiency and yield.
Additively manufactured tooling offers foundries, service bureaus, and other producers of investment casting tooling overall efficiency including cost savings and faster lead times without degrading part properties. Complex and intricate patterns are possible so engineers can optimize the cast for the part rather than for the mold-making process. And the ability to quickly print and test multiple design variations is more easily accomplished versus traditional manufacturing. That said, as a relatively new processing technology, it is often regarded as difficult and adds risk.
“SLA resins designed especially for investment casting offer foundries an investment casting solution that reduces risks and saves time – from printing to finishing,” said Geoff Gardner, Innovation Director Additive Manufacturing at Covestro. With no detectable levels of antimony, Somos WaterShed AF enables investment casting for all types of high-performance metals such as nickel-based superalloys and titanium. “It also reduces the chance of imperfections appearing on the cast part, requiring less rework to finish the part.”
Somos WaterShed AF is highly dimensionally stable thanks to its low moisture uptake, so parts maintain their dimensions and mechanical properties, even under varying environmental conditions. This is particularly important in applications with tight tolerances like e.g. aerospace and aviation, transportation, energy, and utilities. The resin can create accurate, complex patterns with an excellent surface finish. Its low viscosity makes parts easy to print and easy to clean – typical for all resins in the Somos WaterShed family.