Lightweight Cf/SiC Composites with High Fiber Content Fabricated by Binder Jetting Additive Manufacturing and Liquid Silicon Infiltration

Abstract

In this study, Cf/SiC composites with excellent mechanical and thermal properties were prepared by combining binder jetting (BJ) additive manufacturing with liquid silicon infiltration (LSI) process. The introduction of Cf into the Cf/SiC mixed powder reduced its spreading ability, which reduced the density, strength, and precision of the Cf/SiC green parts. However, phenolic resin infiltration and pyrolysis (PRIP) treatment compensated for the decrease in the density of the green parts resulting from the introduction of Cf. By optimizing the number of PRIP cycles to increase the pyrolytic carbon (PyC) content in the carbonized parts, the Cf in the green parts successfully prevented the reaction with molten Si in the LSI and played an important role in strengthening and toughening the composites. The flexural strength, fracture toughness, and thermal conductivity of the Cf/SiC composites reached the maximum values of 316 ± 16 MPa, 4.81 ± 0.12 MPa·m1/2, and 140 W/m·K, respectively. This study presents future opportunities for the cost-effective and efficient industrial manufacturing of Cf/SiC complex structures.