Advanced ceramics have excellent properties such as high temperature resistance, high strength and rigidity, relatively light weight, and corrosion resistance, but they also have an inherent Achilles heel: brittleness. Ceramics will crack or even break when subjected to stress under service conditions, leading to material failure and catastrophic damage. The use of high-strength, high-modulus continuous ceramic fiber and matrix composite is an effective method to improve the toughness and reliability of ceramics. Ceramic fibers can prevent crack propagation, thereby obtaining fiber-reinforced ceramic matrix composites with excellent toughness. In the early 1970s, the concept of continuous fiber reinforced ceramic matrix composites was proposed on the basis of continuous fiber reinforced polymer matrix composites and fiber reinforced metal matrix composites, which opened up a direction for the research and development of high-performance ceramic materials.

Continuous fiber reinforced ceramic matrix composite material is a high performance composite material formed by implanting high temperature resistant continuous ceramic fiber into the ceramic matrix. It has high strength and high toughness, especially non-catastrophic fracture mode different from ordinary ceramics. It has received great attention from researchers from all over the world. With the advancement of fiber preparation technology and other related technologies, people have gradually developed effective methods for preparing such materials, making the preparation technology of fiber-reinforced ceramic matrix composite materials mature. Continuous fiber reinforced ceramic matrix composite materials have begun to be widely used in aerospace, defense and other fields.

For more than 20 years, countries in the world, especially Europe, America and Japan, have conducted a lot of research on the preparation technology and reinforcement theory of fiber-reinforced ceramic matrix composites, and have achieved many important results, and some have reached the level of practicality. On February 10, 2015, GE of the United States successfully verified the world's first rotating low-pressure turbine component on the F414 turbofan engine verification machine, indicating the application of continuous fiber reinforced ceramic matrix composites (SiCf/SiC) in aero engines and gas turbines Up the direction. On June 16, 2015, the ceramic matrix composite tail nozzle designed by the French Safran Group completed the first commercial flight with a CFM56-5B engine and passed the airworthiness certification, marking the era of the use of SiCf/SiC composites for high-temperature components of aero engines advent. After the accident at the Fukushima Daiichi Nuclear Power Plant in Japan on March 12, 2011, the global nuclear power industry puts the research on the fault tolerance of the accident at the top of its development, and Westinghouse has adopted the SiC/SiC composite as the material of choice for the fault-tolerant cladding of the accident.

Boron nitride (BN) fiber is an important inorganic fiber material with a layered crystal structure similar to graphite, also known as "white graphite". BN fiber has good thermal stability, high temperature resistance, chemical corrosion resistance, electric heating performance, radiation resistance, oxidation resistance and high neutron absorption ability. It maintains a stable structure under inert conditions at 2500°C and 850°C in an oxidizing atmosphere. It has extremely broad application prospects in aerospace, new energy and nuclear industry electronics and other high-end technology fields.

Because BN fiber combines the unique excellent properties of BN ceramic materials and fiber materials, many countries in the world have successively started the development of BN fiber and made great progress. Since the middle of the last century, developed countries represented by the United States and Russia have invested a lot of manpower and financial resources in the research and development of BN fiber and its composite materials. At present, they have achieved large-scale production and are used in new weapons, aerospace vehicles, and high-energy Battery and civilian fields. Developed countries have always blocked the key technology of BN fiber preparation on other countries, and products are listed as important strategic embargoed materials. At present, the commonly used preparation methods of BN fiber mainly include inorganic precursor method and organic precursor method.