Effects of high order deformations on the strength of planar lattice materials

• 来源期刊: 力学学报(英文版)
• 年，卷（期）: 2008,（5）
• 页码范围: 533-540
• 页数: 8页
• 语种: 英文
• DOI: 10.1007/s10409-008-0179-5

摘要

Lattice materials have been attractive over the last decade for use as load-carrying structures, energy absorbing elements and heat exchanging structures because of their excellent mechanical properties and multifunctional charac-ters. However, the quantitative analysis accounting for high order deformations upon the collapse of lattice materials, which is important for their applications, has not been repor-ted. An analytical investigation of yield surfaces with res-pect to the high order deformations was carried out for two typical planar lattice materials: triangular and Kagome lat-tices separately. The analytical results were validated by the finite element method (FEM) simulations. It was found that the effect of high order deformation on the yield strength increases with the relative density. The bending effect of the Kagome lattice is more obvious than that of the triangular one with the same relative density and stress state. The yield strength of the Kagome lattice calculated by neglecting the bending effect overestimates the result by more than 10% when the relative density is higher than about 11.1%, which may not be ignored in engineering applications. The yiel-ding surfaces of the two lattice materials demonstrated in the paper also confirm the analytical results.