1. CMC material introduction Ceramic matrix composites (CMC) are a type of composite material that is composited with ceramics as a matrix and various fibers. Ceramic matrix composites refer to the introduction of reinforcing materials into the ceramic matrix to form a composite material with the introduced reinforcing material as the dispersed phase and the ceramic matrix as the continuous phase. It has the characteristics of high temperature resistance, wear resistance, high temperature creep resistance, low thermal conductivity, low thermal expansion coefficient, chemical corrosion resistance, high strength, high hardness and wave penetration, and is widely used in many fields such as aerospace.