Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
10629684 | Journal of the European Ceramic Society | 2012 | 5 Pages |
Abstract
1 mol% of MgO was added together with 7 mol% of Yb2O3 as sintering additives to silicon nitride powder to fabricate advanced silicon nitride ceramics with both high thermal conductivity and low dielectric loss at 2 GHz. The mixed powder was CIPed at a pressure of 120 MPa and was gas-pressure sintered at 1900 °C to >98% of theoretical density. The sintered Si3N4 sample exhibited a high thermal conductivity of â¼100 W mâ1 Kâ1 and a loss tangent (tan δ) of â¼4 Ã 10â4, concurrently. The tan δ was further reduced by half after the heat treatment at 1300 °C for 24 h. The improvement in tan δ due to the annealing was explained from the point of crystallization of the intergranular glassy phase.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Hiroyuki Miyazaki, Kiyoshi Hirao, Yu-ichi Yoshizawa,