Fabrication of Silicon Carbide Fiber-Reinforced Silicon Carbide Matrix Composites Using Binder Jetting Additive Manufacturing from Irregularly-Shaped and Spherical Powders

In this paper, silicon carbide fiber-reinforced silicon carbide (SiC(f)/SiC) composites were fabricated using binder jetting additive manufacturing followed by polymer infiltration and pyrolysis. Spherical SiC powders were produced using milling, spray drying, and thermal plasma treatment, and were characterized using SEM and XRD methods. Irregularly shaped and spherical SiC powders were used to obtain SiC(f)/SiC blends for the application in binder jetting. The effect of SiC powder shape on densification behavior, microstructure, and mechanical properties of binder jetted SiC(f)/SiC composites was evaluated. The highest density of 2.52 g/cm(3) was obtained after six polymer infiltration and pyrolysis cycles. The microstructure and mechanical properties of the fabricated SiC(f)/SiC composites were characterized. Using the spherical SiC powder resulted in higher fracture toughness and hardness, but lower flexural strength compared to the irregularly shaped powder. It was shown that it is feasible to fabricate dense SiC(f)/SiC composites using binder jetting followed by polymer infiltration and pyrolysis.