Details

Autor(en) / Beteiligte

• Zhou, You
• Hirao, Kiyoshi
• Yamauchi, Yukihiko
• Kanzaki, Shuzo
• WCA

Titel

Effects of rare-earth oxide and alumina additives on thermal conductivity of liquid-phase-sintered silicon carbide

Ist Teil von

• Journal of materials research, 2003-08, Vol.18 (8), p.1854-1862

Ort / Verlag

New York, USA: Cambridge University Press

Erscheinungsjahr

2003

Quelle

Springer Journals

Beschreibungen/Notizen

• SiC ceramics were prepared from a β–SiC powder doped with two different sintering additives—a mixture of La2O3 and Y2O3 and a mixture of Al2O3 and Y2O3—by hot pressing and annealing. Their microstructures, phase compositions, lattice oxygen contents, and thermal conductivities were evaluated. The SiC doped with rare-earth oxides attained thermal conductivities in excess of 200 W/(m K); however, the SiC doped with additives containing alumina had thermal conductivities lower than 71 W/(m K). The high thermal conductivity of the rare-earth-oxide-doped SiC was attributed to the low oxygen content in SiC lattice, high SiC–SiC contiguity, and lack of β– to α–SiC polytypic transformation. The low thermal conductivity of the alumina-doped SiC was attributed to the point defects resulting from the dissolution of Al2O3 into SiC lattice and the occurrence of polytypic transformation.