The thermal, electrical and mechanical properties of porous α-SiC ceramics bonded with Ti3SiC2 and β-SiC via low temperature in-situ reaction sintering

Porous SiC ceramics have recently attracted wide attention for their applications in the electrically heatable filter. Further improvement of the thermal and electrical conductivity without sacrificing permeability is a critical parameter for such applications. In the present work, porous SiC/Ti 3 SiC 2 ceramic composites with Ti 3 SiC 2 and micro/nano SiC have been prepared from TiC/Si/α-SiC mixtures at a low sintering temperature (1400 °C). Nano-laminated Ti 3 SiC 2 enhanced the electrical conductivity , while the good thermal conductivity was achieved through in-situ formed nano β-SiC and raw coarse α-SiC in the porous ceramics . Along with the increase of initial α-SiC particle size from 0.76 to 16.13 μm, the permeability, thermal and electrical conductivity improved due to the decreased porosity and increased pore size in porous SiC/Ti 3 SiC 2 ceramics. The results suggested that the decoupling of the electrical conductivity from the thermal conductivity could be tuned by adjusting the initial α-SiC particle size.