Si3N4 and Si2N2O for high performance radomes

Preparation of three-dimensional silica fiber reinforced silicon nitride composites using perhydropolysilazane as precursor

“…Si 3 N 4 ceramics have high mechanical strength, good thermal shock resistance, excellent resistance to rain and sand erosion, an acceptable dielectric constant and low dielectric losses, which are suitable for high temperature electromagnetic window materials for communication, control and thermal protection of spacecraft [1]. However, monolithic ceramics are generally notch-sensitive and exhibit low toughness, the development of three-dimensional (3D) long fiber reinforced Si 3 N 4 composites is being desired.…”

Continuous silica fiber reinforced silica composites densified by polymer-derived silicon nitride: Mechanical properties and microstructures

“…Considering the high mechanical strength, good thermal shock resistance and dielectric properties of silicon nitride [10], preceramic polymer-derived silicon nitride is probably hopeful to densify the SiO 2f /SiO 2 composites and improve the strength. Therefore, in this paper, SiO 2f / SiO 2 composites were prepared and densified by a posttreatment with preceramic polymer-derived silicon nitride.…”

Preparation of amorphous composites with polymer-derived silicon nitride matrix reinforced by three-dimensional silica fiber

“…In order to improve the low toughness of bulk ceramics (such as fused quartz), silica fiber reinforced ceramic matrix composites (SFCMC) have been developed during the last decades as electromagnetic window materials, including short/long silica fiber reinforced silica composites, or silica fiber reinforced phosphate composites [1][2][3]. To our knowledge, Si 3 N 4 ceramic is also a candidate material for high temperature microwave transmission due to the high mechanical strength, good thermal shock resistance, excellent resistance to rain erosion and an acceptable dielectric property [4], but to date few papers have been published on three-dimensional silica fiber reinforced silicon nitride matrix composites (3D SiO 2f /Si 3 N 4 ).…”