Types and characteristics of FRP production technology and sandwich structure manufacturing technology

Sandwich structures are generally composite materials made of three-layer materials. The upper and lower layers of sandwich composites are high-strength and high modulus materials, and the middle layer is thick lightweight materials. FRP Sandwich structure is actually the recombination of composites and other lightweight materials. The sandwich structure is used to improve the effective utilization rate of materials and reduce the weight of the structure. Taking the beam and plate components as an example, in the process of use, one should meet the strength requirements and the other should meet the needs of stiffness. FRP materials are characterized by high strength and low modulus. Therefore, when a single FRP material is used to make a beam and plate to meet the strength requirements, the deflection is often large. If it is designed according to the allowable deflection, the strength will greatly exceed the allowable deflection, resulting in waste. Only by using sandwich structure can this contradiction be reasonably solved. This is also the main reason for the development of sandwich structure.
Due to its high strength, light weight, high stiffness, corrosion resistance, electrical insulation and microwave transmission, FRP Sandwich structure has been widely used in aircraft, missiles, spaceships, templates and roof panels in aviation industry and aerospace industry, which can greatly reduce the weight of buildings and improve the use function. Transparent glass fiber reinforced plastic sandwich structural plate has been widely used in industrial plants, large public buildings and daylighting roofs of greenhouses in cold areas. In the field of shipbuilding and transportation, FRP Sandwich structure is widely used in many components of FRP submarines, minesweepers and yachts. The FRP pedestrian bridge, highway bridge, automobile and train thermal insulation car, etc. designed and manufactured in China adopt FRP Sandwich structure, which meets the multi-performance requirements of light weight, high strength, high stiffness, thermal insulation and thermal insulation. FRP Sandwich structure has become a special material that can not be compared with other materials in the lightning cover requiring microwave transmission.