LAO Xinbin ^{1, 2}, JIANG Weihui ^{1, 2}, LIANG Jian ^{1, 2}, WU Qian¹ , XU Xiaoyang ¹, LI Yage¹

(1. Jingdezhen Ceramic Institute, Jingdezhen 333403, Jiangxi, China ; 2. National Engineering Research Center for Domestic and Building Ceramics, Jingdezhen Ceramic Institute, Jingdezhen 333001, Jiangxi, China)

Abstract: β-Sialon/SiC composite ceramics were prepared by using SiC, Si, Al and α-Al₂O₃ as main raw materials and sintering at 1550°C in N₂ atmosphere. Effects of β-Sialon content on thermal expansion coefficients of the composite ceramics were studied. Results indicated that increasing β-Sialon content could lower thermal expansion coefficient (room temperature-1000 °C) of the composite ceramics dramatically and sample with β-Sialon/SiC mass ratio=70︰30 obtained the lowest thermal expansion coefficient of 3.49×10^-6/°C. The water absorption and porosity also decreased with the increase of the β-Sialon content and the bulk density increased gradually. β-Sialon developed from particles to rod-like grains along with the increase of β-Sialon content.
Key words: β-Sialon; SiC; composite ceramics; thermal expansion coefficient