Hybrid investment casting of Al-Cu-Sc alloy-based lattice structures: Material and process characterization

This paper characterizes the development and optimization of a hybrid investment casting approach tailored for accurately crafting lattice structures with Al-4.5 wt pct Cu-0.4 wt pct Sc alloy, emphasizing precision in mold making, complex surface detailing, and porosity reduction. The core of the research is the description of the manufacturing procedure and the dimensional optimization strategies associated with this hybrid cast lattice geometries. After exploring the lattice shape produced through this advanced casting method, this research explores the microstructural properties and the solidification cooling rate of this hybrid investment casting. Furthermore, this work also addresses the complexity of the manufacturing protocol and the dimensional refinement method. • Developed a hybrid investment casting process for Al-4.5 wt %Cu-0.4 wt %Sc alloys. • Achieved high dimensional accuracy and low porosity in lattice structures. • Surface roughness optimized using different inner pattern materials and treatments. • Solidification cooling rate affects microstructure and secondary dendrite arm spacing. • Degassing system significantly reduced porosity in both joint and strut regions.