With the rapid development of the automobile industry, the annual production and ownership of automobiles continue to increase, resulting in the global energy crisis and environmental pollution problems continuing to intensify. Reducing the carbon emissions of the entire life cycle of automobiles has become a key issue that the global automobile industry needs to solve.
The World Aluminum Association points out that every 10% reduction in vehicle mass can reduce fuel consumption by 6% to 8%. At the same time, in the automotive industry, vehicle lightweighting can help traditional engine vehicles reduce fuel consumption or electric vehicles increase mileage. This is also one of the important means to promote vehicle energy conservation and emission reduction. Among various new lightweight and high-strength materials used in lightweight structural design, carbon fiber composite materials have obvious advantages of high specific strength and specific stiffness. At the same time, they have good heat resistance, acid and alkali corrosion resistance and low corrosion resistance. Thermal expansion coefficient, good specific energy absorption and other advantages make it the first choice for lightweight design of automobile exterior and interior parts.
The car hood is an important part of the car body and has functions such as protecting the engine and isolating noise. Carbon fiber composite materials are used in the design of automobile hoods, which can reduce the weight of automobile hoods and effectively reduce the mass of the car body. With the rapid development of carbon fiber composite manufacturing technology, process technology, and numerical simulation technology at home and abroad, the structural and process design optimization of automobile carbon fiber composite hoods has attracted a large number of researchers to devote themselves to it.
The laminate structure design of the automotive carbon fiber composite hood and the single-layer engineering constants have a significant impact on the overall stiffness of the hood. Duan Chengjin et al. designed a hybrid sandwich structure of carbon fiber and glass fiber laminates (3K carbon fiber plain woven cloth as the surface layer, glass fiber cloth as the internal laminate) for automobile hood components. The quality of the automobile hood components is only It is 2.75kg, which is 4kg lighter than the original metal car hood. The research results show that the interlayer hybrid sandwich structure laminate design achieves controllable cost and the structural strength meets the needs of carbon fiber composite hood laminate structure design. Li Hao used ABAQUS software to conduct computer-aided engineering (CAE) design of the carbon fiber composite hood. Through static model analysis, he found that the four engineering constants (E1, E2, v12, G12) of the carbon fiber composite material single level are closely related to the carbon fiber composite engine. There is a certain correlation between cover stiffness, and the order of its influence is: G12>E2>E1>v12.
The latest research object is to use a multi-stage joint optimization design method of conceptual design, material performance testing and process design to finally achieve lightweight design of carbon fiber composite hoods while meeting various mechanical properties and manufacturing process requirements.
