One of the methods to solve the lightweight problem of some components in aerospace field is to design the three-dimensional ordered porous micro-truss lattice structure to meet the specific needs. Firstly

based on the solid isotropic microstructure with penalization (SIMP) topology optimization algorithm

the lattice cells are optimized under different load boundary conditions with the goal of minimum flexibility

after which the topology optimized lattice cells are geometrically reconstructed. Then

the elastic matrix and elastic modulus surface of the cells under different relative densities are analyzed by using the three-position numerical homogenization algorithm and the mechanical properties of the four cells are compared as well. Physical experiments are conducted on the specimens manufactured by selective laser sintering (SLS) additive manufacturing technology and the experimental results are compared to obtain the mechanical properties of the lattice structure cells with different configurations. Finally

a three-point curved beam is taken as an example to analyze the stress distribution

and the variable density design for lattice structure of Octet cell of the beam is carried out according to the stress distribution. A uniform lattice structure is designed as the control to be compared with the variable density lattice structure in terms of mechanical properties through the three-point bending experiment. The results show that the homogenization simulation results of the four types of cells after optimization and reconstruction are in good agreement with the compression test results. S Star Tet cell has the largest elastic modulus

while Octet cell has the highest shear modulus and good isotropy. Compared with the uniform lattice structure

the bending stiffness and bending strength of the variable density lattice structure is increased by 162.6% and 250.5%

respectively.