Nitrogen (N)-doped conductive silicon carbide (SiC) of various electrical resistivity grades can satisfy diverse requirements in engineering applications. To understand the mechanisms that determine the electrical resistivity of N-doped conductive SiC ceramics during the fast spark plasma sintering (SPS) process, SiC ceramics were synthesized using SPS in an N 2 atmosphere with SiC powder and traditional Al 2 O 3 -Y 2 O 3 additive as raw materials at a sintering temperature of 1850-2000 • C for 1-10 min. The electrical resistivity was successfully varied over a wide range of 10 −3 -10 1 Ω cm by modifying the sintering conditions. The SPS-SiC ceramics consisted of mainly Y-Al-Si-O-C-N glass phase and N-doped SiC. The Y-Al-Si-O-C-N glass phase decomposed to an Si-rich phase and Ndoped Y x Si y C z at 2000 • C. The Vickers hardness, elastic modulus, and fracture toughness of the SPS-SiC ceramics varied within the ranges of 14.35-25.12 GPa, 310.97-400.12 GPa, and 2.46-5.39 MPa m 1/2 , respectively. The electrical resistivity of the obtained SPS-SiC ceramics was primarily determined by their carrier mobility.

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