Thermoelectric properties of boron-rich boride composites prepared through eutectic and peritectic reactions

Boron-rich boride composites were prepared by arc-melting in an argon atmosphere, and their microstructures and thermoelectric properties were studied. B₄C-TiB₂ system was quasi-binary, and the typical lamellar structures indicating a eutectic reaction were observed. The eutectic composition was 25 mol% TiB₂ , and a 6 mol% TiB₂-B₄C composite showed the greatest ZT values of 0.55 at 1100 K. The boron-rich region of Si-B-C system contained a peritectic reaction. The specimens consisting of SiB ₁₄, B₄C and free-Si were prepared. The greatest ZT value of this system was 0.4 at 1100 K for a specimen in which SiB₁₄ is the main phase with several 10 mol% of B₄C and free-Si