A hybrid manufacturing route to high-melting-point metallic lattice structures: integrating material design with process innovation

Metallic lattice structures exhibit exceptional multifunctional attributes, including lightweight design, vibration damping, and energy absorption. Although combining additive manufacturing with investment casting provides a cost-effective fabrication route, current approaches are largely limited to low-melting-point metals. This study demonstrates the fabrication of high-melting-point metallic lattice structures via additive manufacturing assisted investment casting, addressing the fundamental challenge of extending this technique to high-melting-point systems (nickel-based alloy and stainless steel), which offer superior mechanical and thermal performance but are hindered by the lack of suitable preform materials. We present a novel quartz glass-based ceramic preform system, engineered through tailored compositional formulation and sintering protocols, which provide a generic solution by meeting the conflicting demands of high-temperature stability and post-casting removability. Orthogonal experimentation coupled with finite element simulations optimized casting parameters (1550°C pouring temperature, 900°C mold preheating), while multiscale characterization (ProCAST, micro-CT, metallography) fundamentally reveals localized shrinkage porosity at nodal junctions—an inherent solidification challenge in such architectures. Validated cellular automaton finite element (CAFE) modeling further enables grain structure prediction, providing mechanistic insights for solidification control. Beyond the successful fabrication of Inconel 713 lattices, this work establishes generic principles for designing high-temperature soluble ceramics and controlling solidification in complex architectures, establishing a scalable platform for high-performance metallic lattice structures and offering a transferable framework applicable to a broad range of high-melting-point alloys.