Fabrication And Mechanical Properties Of Ultra-light Cellular Materials

As typical organic texture, cellular materials are very common in the natural world, such as woods and bones,integrated with light,load bearing and multifunctional applications to the materials. The mechanical properties and multifunctional behaviors depend upon the lattice relative density, lattice topology and the material used to make the trusses. Compared with the traditional, the fabrication of cellular materials which have more designable with controlled truss to meet the requirements of engineering. The corrugation-pyramidal truss core sandwich panels and periodic truss structures were made and discussed in this thesis.Firstly, under the premise of small deformations, the response of structures have been investigated on the bases of continuous displacements and equilibrium formulation, deriving the analytical expressions of the effective elastic constants of all the structures. Secondly, The critical buckling load of the pyramidal structure and “corrugated-pyramidal” structure are founded with the finite element simulation. Lastly, the two kind of PVC lattice structures are made by Rapid Prototyping 3D printing technology, and then the compression test is used to obtain the mechanical property of the structures under different relative densities.The mechanical properties of periodic truss is investigated in the latter part. Firstly, the response of structures have been investigated on the bases of continuous displacements and equilibrium formulation, deriving the analytical expressions of the effective elastic constants of the structure. The equivalent compression stiffness of periodic truss is calculated with the finite element simulation. Lastly, the periodic truss of 304 steel and composite material are made with the method of interlocking, and then the compression test was used to obtain the mechanical property of the structure.