Optimal design of three-dimensional non-uniform nylon lattice structures for selective laser sintering manufacturing

摘要

As a kind of novel multifunctional structure with three-dimensional pores characterized by low relative density, latticestructures can attain a lightweight design while maintaining high specific mechanical properties in three-dimensional solidstructures. Focusing on the challenge of finding the optimal design of lattice structures in the design object, a design andmodeling method of non-uniform three-dimensional lattice structures is proposed while ensuring the selective laser sintering manufacturability. Optimization for cell type, cell size, and strut size distribution of lattices is specified with themechanical properties analyzed and the material model calculated beforehand. The manufacturing constraints are analyzed and expressed in topology optimization and the optimal distribution of topology optimization results is mapped tothe strut size distribution of lattice cells. The rapid and automatic computer-aided design modeling of optimized structures is realized by the parametric definition and assembling of lattice components. Finally, the non-uniform structuresare successfully manufactured by selective laser sintering and it is shown by means of finite element analysis and experiments that the proposed design approach can improve the mechanical performance compared to the uniform latticestructure under the same weight reduction. And for the design object in this study, body-centered structure with cellsize a = 4:5 mm is chosen as the optimal cell type and cell size under the given selective laser sintering manufacturingconstraints.