Electrical and Thermal Properties of SiC Ceramics Sintered with Yttria and Nitrides

• Published in: Journal of the American Ceramic Society Vol. 97; no. 9; pp. 2943 - 2949
• Main Authors: Kim, Kwang Joo, Lim, Kwang-Young, Kim, Young-Wook
• Format: Journal Article
• Language: English
• Published: Columbus Blackwell Publishing Ltd 01.09.2014; Wiley Subscription Services, Inc
• Subjects: Ceramic sintering; Ceramics; Electric properties; Electrical resistivity; Heat conductivity; Nitrides; Silicon carbide; Sintering; Temperature effects; Thermal conductivity; Thermal properties; Yttrium oxide
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/jace.13031

The electrical and thermal properties of SiC ceramics containing 1 vol% nitrides (BN, AlN or TiN) were investigated with 2 vol% Y2O3 addition as a sintering additive. The AlN‐added SiC specimen exhibited an electrical resistivity (3.8 × 101 Ω·cm) that is larger by a factor of ~102 compared to that (1.3 × 10−1 Ω·cm) of a baseline specimen sintered with Y2O3 only. On the other hand, BN‐ or TiN‐added SiC specimens exhibited resistivity that is lower than that of the baseline specimen by a factor of 10−1. The addition of 1 vol% BN or AlN led to a decrease in the thermal conductivity of SiC from 178 W/m·K (baseline) to 99 W/m·K or 133 W/m·K, respectively. The electrical resistivity and thermal conductivity of the TiN‐added SiC specimen were 1.6 × 10−2 Ω·cm and 211 W/m·K at room temperature, respectively. The present results suggest that the electrical and thermal properties of SiC ceramics are controllable by adding a small amount of nitrides.