Thermoelectric properties of β-FeSi
2 with SiC dispersion prepared by mechanical alloying were investigated. The FeSi
2 alloys doped with Mn or Co (p-type Fe
0.92Mn
0.08Si
2, n-type Fe
0.98Co
0.02Si
2) were prepared by arcmelting in Ar. Mixtures of these FeSi
2 alloys with Si+C powders were mechanically alloyed for 72ks, and hot pressed at 1173K for 3.6ks under 25MPa. XRD showed that β-FeSi
2 and SiC were formed during hot pressing Si+C addition had little influence on the thermoelectric power of β-FeSi
2. On the other hand, the resistivity increased with increasing Si+C addition. The thermal conductivity drastically decreased by about 30% with increasing Si+C addition in all temperature range. This is considered to be due to the SiC dispersion in β-FeSi
2. SiC phase restrained the growth of β-FeSi
2 phase and phonons scattering at grain boundaries increased, therefore thermal conductivity decreased. SEM photographs showed that 10-20μ m SiC particles dispersed in the β-phase. The figure of merit, Z=α
2/(ρ⋅k), where α : thermoelectric power, ρ : resistivity, K : thermal conductivity, of Fe
0.92Mn
0.08Si
2 added 5wt.% Si+C is higher than that of Fe
0.92Mn
0.08Si
2 without Si+C addition. As a result, it is effective to add Si+C to p-type Fe
0.92Mn
0.08Si
2.
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