Preparation And Mechanical Behavior Of Carbon Fiber Lattice Materials

Carbon fiber lattice-frame materials have lightweight and high strength characteristics,which are considered as a new type of structural material with superior mechanical properties.It has been widely used in aerospace,transportation,naval equipment and new energy fields.The Kagome configuration,one of the three typical configurations of latticeframe materials,has a relatively unique form of cross-connection of the core rods,which theoretically provides better mechanical properties and resistance to instability than other lattice-frame configurations.The design of core cross-connections of Kagome lattice-frame materials in the preparation is a challenge,which restricts the development of its preparation process.Based on the idea of mortise-and-tenon joints,a new preparation process is proposed.The constituent rods of the unit cell are self-locking at the nodes,while semi-tenon connections are also used between the cores and the panels,increasing the deformation synergy effect of unit cell under carrying load.All above better solve the problems of core rod node connection and face-core connection,and induce semi-flexible connection characteristics and the deformation tolerance capacity.The out-of-plane compression properties of Kagome lattice-frame materials were investigated,and a theoretical prediction model for the out-of-plane compression modulus and strength of the structure was constructed.Out-of-plane compression tests and finite element simulations were carried out to obtain load-bearing characteristics curves for different heights and rod thicknesses of lattice-frame materials.The failure modes,damage evolution mechanisms and energy absorption properties of the structures are revealed.The mortise and tenon jointing process effectively improves the structural coordinate deformation ability.Compared to other lattice-frame configurations,the Kagome configuration exhibits superior mechanical properties,particularly in terms of load-bearing capacity after damage to the structure.The in-plane compression properties of Kagome configuration lattice-frame materials were investigated,and a theoretical prediction model for in-plane compression failure modes and ultimate loads were constructed.In-plane compression tests and finite element simulations were carried out to obtain load-displacement curves for lattice-frame materials of different lengths and panel thicknesses.The fiber damage of panels and core rods was investigated,revealing the progressive failure mode and the damage evolution mechanism.The results show that the face-core connection of this structure can better suppress the face-core debonding problem,and effectively improve the shear resistance of the latticeframe material subjected to the in-plane compression.