Temperature Dependence of the Electrical Properties and Seebeck Coefficient of AlN–SiC Ceramics
Abstract:AlN–SiC ceramics composed of AlN–SiC solid solutions were fabricated by pressureless sintering without sintering additives. The microstructure and electrical properties of the AlN–SiC ceramics were investigated for compositions between 0 and 75 mol% AlN. The AlN–SiC ceramics had a porous structure, and a 2H polytype was found in all compositions. The electrical conductivities and Seebeck coefficients of the AlN–SiC ceramics increased with temperature. The electrical conductivity of 25 mol% AlN–75 mol% SiC ceramics was the highest in all compositions: 32.7 S/m at 300°C. In contrast, the electrical conductivity of 75 mol% AlN–25 mol% SiC ceramics was much lower than that of other samples: 10−2 S/m at 300°C. The Seebeck coefficient of 50 mol% AlN–50 mol% SiC ceramics was the highest of all samples: 210 V/K at 300°C. The electrical and thermoelectrical properties of SiC can be controlled by the formation of AlN–SiC solid solutions.
Document Type: Research Article
Affiliations: Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama-shi 240-8501, Japan
Publication date: 2006-04-01