Thermal conductivity of pressureless sintered Si3N4 ceramics with Li-exchanged zeolite

• Main Authors: Matović Branko Z., Bošković Snežana B.
• Format: Article
• Language: English
• Published: Serbian Chemical Society 2004-01-01
• Series: Journal of the Serbian Chemical Society
• Subjects: pressureless sintering; silicon nitride; thermal conductivity
• Online Access: http://www.doiserbia.nb.rs/img/doi/0352-5139/2004/0352-51390409705M.pdf
• ISSN: 0352-5139; 1820-7421

The effects of temperature on the thermal conductivity of Si3N4 sintered with Li-exchanged zeolite were investigated. The highest conductivity was measured for the ceramics sintered with 10 % of additive. The complete α→β-Si3N4 transformation and maximum density (> 98 % TD) were attained with the sample sintered at 1650 ºC. However, the results show that Al and O from the additive dissolve into the β-Si3N4 structure which act as phonon scattering sites resulting in a lowering of the conductivity and a weaker temperature dependance of the conductivity.