A composite material is a mixture. It has played a great role in many fields and replaced many traditional materials. Composite materials are divided into metal and metal composite materials, non-metal and metal composite materials, and non-metal and non-metal composite materials according to their composition. According to its structural characteristics, it is divided into:

1. Fiber-reinforced composite materials: composed of various fiber reinforcements placed in a matrix material. Such as fiber reinforced plastics, fiber reinforced metals, etc.

2. Sandwich composite materials: composed of surface materials and core materials with different properties. Usually the surface material is strong and the core material is light and low in strength, but has a certain stiffness and thickness. Divided into solid sandwich and bee type. Sirion's Airex products are foam core materials with outstanding performance and are widely used in shipbuilding, aviation and industrial fields.

3. Fine-grained composite materials: evenly distribute hard fine particles in the matrix, such as dispersion-strengthened alloys, cermets, etc.

4. Hybrid composite materials: composed of two or more reinforcing phase materials mixed in one matrix phase material. Compared with ordinary single-reinforced phase composite materials, its impact strength, fatigue strength and fracture toughness are significantly improved, and it has special expansion properties.

Composite materials can be mainly divided into two categories: structural composite materials and functional composite materials according to their performance characteristics:

1. Structural composite materials: Materials used as load-bearing structures are basically composed of matrix components that can withstand strength-bearing components and can connect reinforcements to form an integral material while also transmitting force. Nowadays, some boards with excellent strength and fire resistance, such as Banova SBc and Banova VBC, can be used in the interior structures of rail vehicles and houses. They can achieve the lightweight requirements of materials while maintaining good load-bearing capacity.

2. Functional composite materials: Generally composed of functional components and matrix components. The matrix not only plays the role of forming a whole, but also can produce synergy or enhance functions. Functional composite materials refer to composite materials that provide other properties in addition to mechanical properties. Such as: conductive, superconducting, semiconducting, magnetic, piezoelectric, damping, wave absorption, wave transmission, screen grinding, resistance, prevention, sound absorption, isolation, etc. to highlight a certain function. Collectively called functional composite materials.

Examples of common composite materials:

1. Carbon fiber composite materials: composite materials using carbon or graphite fibers as reinforcing materials.

2. Aramid composite materials: composite materials using aramid as reinforcing materials.

3. Glass fiber composite materials: composite materials with glass fiber as reinforcing material.

4. Boron fiber composite materials: composite materials with boron fiber as reinforcing material.

7. Chopped fiber composite materials: composite materials using chopped fibers as reinforcing materials.

8. Ultra-hybrid composite materials: Composite materials made of fiber reinforced materials and metal reinforced with the same resin matrix.

9. Aramid-reinforced aluminum alloy laminate (ARALL laminate): an interlayer super-hybrid composite material made of aramid/epoxy resin prepreg and aluminum alloy laminates and solidified under pressure.

10. Glass fiber reinforced aluminum alloy laminate (GLARE laminate): an interlayer super hybrid composite material made of glass fiber/epoxy resin prepreg and aluminum alloy laminates and solidified under pressure.

11. Carbon fiber reinforced titanium alloy laminate: an interlayer super hybrid composite material made of carbon fiber/resin prepreg and titanium alloy laminates and pressed and solidified.

12. Nanocomposite: A composite material in which a certain component or a certain direction of a certain component reaches the nanometer scale.

13. Intelligent composite materials: Composite materials that have sensing, driving, and control components embedded inside the composite materials and can respond timely, sensitively, and accurately to changes in the external environment.