Three-dimensional printing of Ti₃SiC₂-based ceramics

In the present work, we explored the feasibility of fabricating Ti ₃SiC₂-based ceramics by a near-net-shape fabrication process of three-dimensional printing (3D printing) combined with liquid silicon infiltration (LSI). The porous ceramic preform was fabricated by 3D printing TiC powder with dextrin as a binder. The heat-treated preforms contained bimodal pore structure with interagglomerate pores (dâ23 μm) and intraagglomerate pores (dâ1 μm). Upon infiltration in Ar atmosphere at 1600°-1700°C for 1 h, silicon melt infiltrated the pores and reacted with TiC to yield Ti₃SiC₂, TiSi_2, and SiC. The effects of silicon content and infiltration temperature on the phase composition of the Ti₃SiC₂-based composites were also studied. After LSI at 1700°C for 1 h, the composites with an initial TiC:Si mole ratio of 3:1.2 attained a bending strength of 293 MPa, a Vickers hardness of 7.2 GPa, and an electrical resistivity of 27.8 μÎ