Specific Sensitivity Analysis and Imitative Full Stress Method for Optimal BCCZ Lattice Structure by Additive Manufacturing

Abstract

Additive manufacturing (AM) can quickly and easily obtain lattice structures with light weight and excellent mechanical properties. Body-centered cubic (BCC) lattice structure is a basic type of lattice structure. BCC with Z strut (BCCZ) lattice structure is a derivative structure of BCC lattice structure, and it has good adaptability to AM. Generally, the thickness of each pillar in the BCCZ lattice structure is uniform, which results in the uneven stress distribution of each pillar. This makes the potential of light weight and high strength of the BCCZ lattice structure not fully played, and the utilization rate of materials can be further improved. This paper designs an optimization method. Through the structural analysis of a BCCZ lattice structure, an optimization method of a BCCZ lattice structure based on parametric modeling parameters is presented. The section radius of all pillars in the BCCZ lattice is taken as a design variable, and the specific sensitivity analysis method and simulated full stress optimization idea are successively used to determine the optimal section radius of each pillar. Finally, the corresponding model is designed and samples are manufactured by LPBF technology for simulation and experimental verification. The results of simulation and experiment show that the strength limit of the optimized parts increased by 18.77% and 18.43%, respectively, compared with that before optimization.