Microstructural Development of SiC Ceramics by Liquid-Phase Sintering with Spark Plasma Sintering Technique

Sub-micron and nano-sized β-SiC powders were sintered with AlN and Y2O3 as sintering additives by spark plasma sintering (SPS). The sintered densities reached >95% of theoretical with a different molar ratio of AlN to Y2O3 at total amount of 10vol% and temperature of 1900oC for 10min in N2 atmosphere under a pressure of 30MPa. With increasing amount of the AlN additive, the size of SiC grains decreased and the shape changed from globular to columnar. The fully densified SiC at AlN:Y2O3=95:5mol% had an average grain size of 0.5-1µm and 50-100nm in diameter by using sub-micron and nano-sized SiC starting powders, respectively. Flexural strength of the specimen having grain size of 0.5-1µm was approximately 1200MPa at room temperature.

Download Full-text

Inhibition of grain growth in liquid-phase sintered SiC ceramics by AlN additive and spark plasma sintering

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2010.04.006 ◽

2010 ◽

Vol 30 (10) ◽

pp. 2117-2122 ◽

Cited By ~ 34

Author(s):

Mikinori Hotta ◽

Junichi Hojo

Keyword(s):

Liquid Phase ◽

Grain Growth ◽

Spark Plasma Sintering ◽

Sic Ceramics ◽

Plasma Sintering ◽

Spark Plasma

Download Full-text

Effect of Doped CeO with Si3N4 Powders on the Densification Mechanism During

10.21203/rs.3.rs-136510/v1 ◽

2021 ◽

Author(s):

Yao Liu

Keyword(s):

Liquid Phase ◽

Relative Density ◽

Stress Exponent ◽

Spark Plasma Sintering ◽

Liquid Phase Sintering ◽

Creep Model ◽

Stress Regime ◽

Densification Mechanism ◽

Plasma Sintering ◽

Spark Plasma

Abstract The densification mechanism of doped CeO with Si3N4 powder during Spark Plasma Sintering (SPS) was investigated under temperatures ranging from 1500 to 1750 °C at soaking pressures of 30, 40, 50 MPa. Results showed that the relative density of Si3N4 ceramics sintered at 1650 °C and 30 MPa was 97.9%. A creep model was employed to determine the mechanism, which can be interpreted on the basis of the stress exponent (n). The results showed that the mechanism was controlled by liquid phase sintering at low effective stress regime (n=1).

Download Full-text

Liquid Phase Sintering of α-Si3N4 by Spark Plasma Sintering

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.1062 ◽

2007 ◽

Vol 336-338 ◽

pp. 1062-1064 ◽

Cited By ~ 1

Author(s):

Fa Qiang Yan ◽

Fei Chen ◽

Qiang Shen ◽

Lian Meng Zhang

Keyword(s):

Liquid Phase ◽

Spark Plasma Sintering ◽

Sintering Temperature ◽

Liquid Phase Sintering ◽

Sintering Behavior ◽

Sintering Aids ◽

Factors Influencing ◽

Plasma Sintering ◽

Spark Plasma ◽

Si3n4 Ceramics

In this study, spark plasma sintering (SPS) was applied to prepare α-Si3N4 ceramics of different densities with magnesia, silicon dioxide, alumina as the sintering aids. The sintering behavior and liquid phase sintering (LPS) mechanism were discussed and the factors influencing the density of the prepared samples were analyzed. Microstructures of sintered samples were observed and the phase compositions were analyzed. The results showed that α-Si3N4 ceramics can be sintered by SPS based on the reaction among α-Si3N4 and sintering additives which lead to the liquid phase and the density can be well controlled from 2.48 to 3.09 g/cm3 while the content of the sintering aids changes from 10% to 28.5% and sintering temperature from 1400°C to 1500°C.

Download Full-text