Development of Silicon Nitride-Based Ceramic Radomes — A Review

Abstract

Radome is an aerodynamic structural part attached to the fore-end of a missile. It transmits electromagnetic signals with minimum attenuation and also protects radar communication system, and thus, the radomes are made of ceramics as they have desirable properties required by the radomes. The flexural strength, dielectric constant, and loss tangent values of various ceramic materials used in the development of radomes are important in the selection of radome materials. Different nose cone shapes of missile radomes are also important. Ceramic materials show variational properties with sintering time, temperature, and other additives. The existing different near-net shape fabrication techniques for manufacturing of ceramic radomes are discussed and compared. Gelcasting is one of the manufacturing techniques to produce radomes with homogeneous and high green strength. Gelcast parts of silicon nitride ceramics are hard, tough, brittle, and wear-resistant and are difficult to machine using conventional methods of machining. Therefore, laser-assisted machining is used for fine finish of ceramic radomes with excellent surface integrity and productivity. This paper deals with a review of development of ceramic radomes, manufacturing methods for variety of applications.