Controlled microstructure, thermal and mechanical property anisotropy of binder jetting 3D-printed SiC ceramics by reaction bonding

This study explores the anisotropy in SiC ceramics fabricated by Binder Jetting (BJ) 3D printing. BJ-3D printing forms complex SiC shapes but introduces interlayer defects, causing anisotropy. SiC green bodies were printed in various directions, and their mechanical properties were tested. The green bodies built parallel to the printing direction had the highest flexural strength, while other directions showed a 40 % – 53 % reduction. After reaction bonding and sintering, the anisotropy decreased significantly. The flexural strength of samples built parallel to the printing direction was 229.36 MPa, with other directions showing only a 7 % – 14 % reduction. The anisotropy evaluation index (σ₀/σ_x) decreased from 2.13 to 1.09 after reaction bonding. Thermal properties of sintered SiC in different directions showed no significant differences. Reaction bonding effectively reduces anisotropy, providing valuable insights for BJ-3D printed SiC ceramics.