Abstract Scope |
Radomes protect the antenna from the harsh environment encountered when flying at hypersonic speeds. The radome material must have a low dielectric constant and loss so as not to attenuate GHz radar waves. Silicon nitride is being considered as a radome material because it meets these criteria; it also has high mechanical strength and toughness, low coefficient of thermal expansion, and good thermal shock resistance. The A-sandwich design is a common broadband radome design. It is constructed with a porous core and dense skins on each side of the core. In this work, fabrication of a silicon nitride porous core using various methods, including extrusion concepts and pore forming agents, will be discussed. |