Additive manufacturing of high-density silicon carbide ceramics through post-processing spark plasma sintering

Abstract

This research advances the field of additive manufacturing (AM) of silicon carbide (SiC) ceramics by integrating spark plasma sintering (SPS) to enhance material density, mechanical strength, and thermal properties. Traditional AM techniques struggle to achieve the high-density SiC required for demanding applications, such as aerospace engineering, where high thermal conductivity and mechanical strength are paramount. Our study addresses these challenges by incorporating SPS as a post-processing step, achieving near-theoretical maximum densities and significantly reducing porosity, thereby resulting in outstanding thermal conductivity in SiC ceramics. We developed a specialized SiC ink optimized for 3D printing, ensuring structural integrity after deposition through tailored rheological properties. The application of SPS facilitates rapid, uniform sintering, essential for attaining superior density, mechanical properties, and thermal performance. Our experimental results, confirmed through scanning electron microscopy analysis, demonstrate significant microstructural properties, mechanical strength, and thermal conductivity, showcasing the effectiveness of integrating SPS in AM processes. This innovative approach not only expands the capabilities of AM in producing complex, high-density ceramic structures but also broadens the potential applications of SiC in demanding environments.