Experimental Study On Mechanical Response Characteristics Of Carbon Fiber Composite Sandwich Structure Under Impact Loading

Carbon fiber composite sandwich plate has been widely used in aerospace,shipbuilding,automobile,medical and other advanced fields due to its excellent mechanical properties.Compared with the traditional single material structure,the new structure of carbon fiber composite sandwich plate is more suitable for the demand of the development of the times.Carbon fiber plate has many advantages such as low density,high strength,strong corrosion resistance and wear resistance.Carbon fiber plate and cellular lightweight foam composed sandwich plate combine the advantages of these two materials.The impact resistance and energy absorption capacity are very good,such sandwich plate is often used as a structural impact resistance protection.The impact resistance protective structure protects the safety of life and property,it is necessary to study the failure modes and impact resistance of this kind of sandwich plate.In this paper,the dynamic response,typical failure mode and impact resistance of carbon fiber composite sandwich plate are studied by experimental method.The dynamic response characteristics of carbon fiber composite sandwich plate are analyzed,and the influence of relevant parameters on the dynamic response of the structure is discussed.The typical failure mode and failure mechanism of sandwich plate are studied by analyzing the failure of sandwich plate surface and cross section.The impact resistance and energy absorption capacity of the structure were evaluated according to the deflection of the center point of the rear sheet of the sandwich plate.The main research contents of this paper are as follows:(1)The influence of core thickness,density,arrangement and normalized impulse on the dynamic response of sandwich structure is analyzed by using the three-dimensional digital image correlation technology to obtain the deflection cloud diagram of rear sheet,the deflection variation of different points on rear sheet and the deflection variation of cross-section of sandwich plate.(2)According to the theoretical formula,the failure mechanism of the carbon fiber board is analyzed.Through the final failure morphology of the composite sandwich plate,the effects of the thickness,density and arrangement of the core layer of the sandwich plate on the typical failure mode of the sandwich structure are discussed respectively.The influence of various structural parameters on the compression of the core layer is analyzed through the cross-section of the sandwich plate.The results show that increasing the number of core layers of the sandwich plate can reduce the compression of the core layer.(3)The final deflection deformation of the center point of the rear sheet of the sandwich plate is used to evaluate the impact of the relevant parameters of the structure on the impact resistance of the sandwich structure itself.In addition,the energy absorption capacity of various types of sandwich plates was evaluated by citing a relevant formula.