Reseach On Anisotropy And Buckling Of 3D Printed Honeycomb Structures With Experimental Verification

In recent years,3D printing technologies have developed rapidly and has become more sophisticated.Some relatively complicated parts that are difficult to process with conventional methods can be manufactured using 3D printing technologies.Using this feature of 3D printing technology,it can be applied to many fields such as automotive transportation field as well as the aerospace field to process some sophisticated and complex parts.Honeycomb structure as a lightweight and high-strength structure can be applied to the automotive and aerospace fields to reduce the weight of the structure.The Kagome honeycomb structure is a composite honeycomb,which is complicated compared to the traditional hexagonal honeycomb structure,but its performance is good.It can be applied to honeycomb sandwich materials for automobiles and reinforced cylindrical shell structures for aviation rockets.Because of its relatively complex structure,traditional milling methods are prone to buckling deformation.3D printing technology can solve this problem.At the same time,since Kagome honeycombs are orthotropic,3D printing materials also exhibit orthotropicity,and anisotropy is one of the main reasons for the buckling and deformation of thin-walled parts,by changing various items of Kagome honeycomb structure.Parameters can be designed for isotropic 3D printed Kagome honeycomb structures.Therefore,it is necessary to study the mechanical parameters that affect the orthotropicity of the two.The main research contents of this article are as follows:(1)The analytical expressions of the constitutive equation and mechanical properties of orthogonal Kagome honeycomb structures printed using 3D printing are given.The performance indexes of orthogonal Kagome honeycomb structures subjected to stretching and shear in the plane,such as Young's modulus,shear modulus,and Poisson's ratio,were analyzed.The relationship between the constitutive matrix and elastic modulus,anisotropy ratio,and relative density of the Kagome honeycomb structure was obtained through analysis.(2)The Young's modulus of the 3D printed material in the transverse and longitudinal directions was measured by a uniaxial tensile test.Then,combining analytic expressions with experimental results,we can predict the maximum Young's modulus and maximum shear modulus for 3D printed Kagome honeycombs,while also studying the isotropic properties of honeycomb structures.The correctness of the analytical formula was verified by a 3D printing tensile test.We also derive the initial yield strength surface and the curved surface equation.(3)Through the isotropic analysis,we get the parameters of each isotropy of the Kagome honeycomb structure with 3D printing.The honeycomb structure in this case is extended to a three-dimensional cylindrical three-dimensional structure,that is,applied to a reinforced cylindrical shell structure of a rocket,a three-dimensional CAD model is designed to be scaled and scaled,and a 3D printer is used for printing and manufacturing.Then,a series of uniaxial compression experiments are carried out and the mechanical properties of the specimens are measured by experiments.The mechanical properties of Kagome honeycomb structures are compared with those of other parameters.