Due to the low strength, hardness, and elastic modulus of BN ceramics, high thermal conductivity, insufficient rain erosion resistance, and difficulty in making larger-shaped components, single-phase BN ceramics have not yet been truly used in radomes. The current research mainly focuses on two categories: BN wave-transparent fiber.

Boron nitride wave transparent fiber

BN fiber combines various excellent properties unique to BN materials and fiber materials. Compared with some inorganic fibers (such as silicon nitride fiber, quartz fiber, etc.) suitable for hypersonic missile application environments, it has high temperature resistance and high temperature resistance. It has excellent mechanical properties, excellent dielectric properties, and can absorb neutrons. The oxidation resistance temperature of BN fiber is higher than that of carbon fiber and boron fiber, and it can be used for a long time in an oxidizing atmosphere below 900 ℃ and an inert atmosphere below 2800 ℃.

Research progress and application of boron nitride wave-transparent fibers

Currently, in ceramic matrix composite materials that can be used as heat-proof and wave-transparent components such as missile antenna windows and radomes, quartz fibers and BN fibers with good heat resistance and dielectric properties can be used as reinforcing fibers. Compared with quartz fiber, BN fiber has the following advantages:

(1) In an inert atmosphere within 2000°C, the crystal grains will not grow and the strength will not decrease;

(2) Excellent dielectric properties and a wider range of collective material selection options for composite materials;

(3) Excellent high-temperature performance, which can ensure the reliability and safety of components during the friction and heating process of the aircraft.

Therefore, BN fiber has good application prospects in the field of aerospace wave transmission. The excellent properties of BN fiber have always been paid attention to by military, aerospace and other related fields. In recent years, research in this field has been very active at home and abroad.