| With the increase of load intensity on the battlefield and the change of combat mode,combat devices will be seriously deformed and damaged in the battlefield environment,threatening the combat effectiveness of the army and the safety of combatants.In order to improve the anti-explosion performance of the device,the research on the optimal design of sandwich structure has become one of the hot issues in the field of explosion protection.As a new material,carbon fiber metal laminate has a wide application prospect in the field of explosion protection.However,under the action of explosion load,the propagation of explosion shock wave in the structure is sensitive to the laminated structure of panel and the geometry of sandwich.How to reasonably design the laminated structure and sandwich microstructure of fiber metal laminate remains to be further discussed,which is one of the most important factors for the design of explosion resistance of fiber metal laminate sandwich structure.Taking the sandwich structure of carbon fiber metal laminate as the research object,this paper compares the anti-explosion mechanism of equal mass honeycomb sandwich structure and metal hollow ball sandwich structure under explosion load.The effects of honeycomb sandwich layer height,hollow ball sandwich layer wall thickness and panel material on the explosion resistance of sandwich structure are discussed.The main research work of this paper is as follows:1.Based on the dimensional analysis theory,an explicit formula for calculating the stress of metal hollow sphere platform under impact load is established by considering the mechanical and geometric parameters of metal hollow sphere.Considering ideal elastoplastic and bilinear elastoplastic metal hollow spheres,according to Π theorem,the mathematical expression between the platform stress of hollow sphere and the material and geometric parameters is obtained.The verification shows that the platform stress calculation formula based on dimensional analysis can accurately evaluate the platform stress of ideal elastic-plastic hollow sphere and bilinear elastic-plastic hollow sphere under impact load,especially for bilinear elastic-plastic hollow sphere.At this time,the classical Reid formula based on rigid plasticity has failed.2.The explosion resistance of carbon fiber metal laminate sandwich structure is studied.The effects of sandwich wall thickness,height and panel material on the explosion resistance of carbon fiber metal laminate sandwich structure are discussed,and the explosion limit load of each sandwich composite structure is determined.The results show that under the condition of equal mass,compared with the honeycomb sandwich structure,the metal hollow ball sandwich structure shows better explosion shock wave dissipation ability.And the increase of the number of core layers is more conducive to the diffusion of interlayer explosion shock wave from the explosion center area to the surrounding structure,so as to improve the explosion resistance of the structure.The local deformation modes of carbon fiber metal laminate sandwich structure with different sandwich height and thickness diameter ratio are different.With the increase of panel toughness,its explosion resistance is significantly improved. |
