Experimental and Numerical Analysis of Lattice Structures with Different Heterogeneities

Lattice structures with optimized material distributions can achieve unique mechanical properties such as high stiffness-to-weight ratio. However, the numerical analysis of the mechanical properties of heterogeneous lattice structures is challenging. In this research, three numerical approaches, including the beam element model, tetrahedral element model, and two- stage homogenization model, were used to predict the stiffness of lattice structures with different heterogeneities. Compression tests were conducted to evaluate the accuracy of the simulation results of each numerical approach. It was found that the accuracy of the numerical model varies with the increasing of heterogeneities. The beam element model significantly underestimated the stiffness. The tetrahedral element model is the most accurate, but the computational cost is extremely higher than others. The results also indicated that, although the homogenization-based numerical model can substantially reduce the computational cost, the accuracy can be compromised due to the heterogeneity of lattice structures.