Effect of laser power on mechanical properties of SiC composites rapidly fabricated by selective laser sintering and direct liquid silicon infiltration

Selective laser sintering (SLS) is a promising additive manufacturing technique for the efficient fabrication of SiC composites with complex structures. In this work, a novel strategy for fabricating SiC composites via SLS of carbon fiber combined with liquid silicon infiltration is reported. The SLS-powder composed of chopped carbon fiber (C-f) and phenolic resin (PR) mixed powder, a C-f/PR green body with a tailored microstructure was obtained by SLS. The printed green body had a low PR content (25 vol%), high printing stability, and excellent strength. Finally, high-performance SiC composites are prepared via the liquid silicon infiltration, with optimized density, flexural strength, elastic modulus, and fracture toughness values of 2.719 +/- 0.008 g/cm(3), 266 +/- 5 MPa, 248 +/- 3 GPa, and 2.87 +/- 0.07 MPa m(1/2), respectively. This strategy demonstrates an efficient approach to produce near net-shape high-performance SiC composites with a designable complex structure.

Automated summary

A novel strategy for fabricating SiC composites via selective laser sintering (SLS) of carbon fiber combined with liquid silicon infiltration is reported. The SLS-powder composed of chopped carbon fiber and phenolic resin mixed powder is used to obtain a green body with a tailored microstructure. High-performance SiC composites with optimized density, flexural strength, elastic modulus, and fracture toughness are prepared through liquid silicon infiltration.