We have described properties of SiC for n-type thermoelectric conversion materials. SiC sintered at 2300 deg C in 0.93 MPa nitrogen pressure for 2 h had a power factor of 9.3x10~(-4) Wm~(-1)K~(-2) at 800 deg C. This specimen also showed electrical conductivity of 3.4 x10~4 OMEGA~(-1)m~(-1) and a Seebeck coefficient 165 mu VK~(-1), the highest one in the present study. These experimental results are interpreted as follows: The high electrical conductivity is due to the suppression of the /3 to a phase transition, and the high Seebeck coefficient due to the lower density of stacking faults and the presence of large grains in SiC sintered at high temperature. The present work developed SiC with improved properties for thermoelectric conversion materials that can be used in practical applications. We report here properties measured up to a maximum of 800 deg C. We can expect high performance at even higher temperatures because SiC has good high temperature stability.
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