基于变截面支柱的点阵强化设计方法  

Lattice reinforcement design method based on variable cross-section pillars

作　　者：李昊 朱奎 孙丰勇 韩基泰 李寅 LI Hao;ZHU Kui;SUN Fengyong;HAN Jitai;LI Yin(School of Automation,Nanjing University of Information Science and Technology,Nanjing 210044,China;School of Automation,Wuxi University,Wuxi 214105,China)

机构地区：[1]南京信息工程大学自动化学院,南京210044 [2]无锡学院自动化学院,无锡214105

出　　处：《机械强度》2025年第3期143-150,共8页Journal of Mechanical Strength

基　　金：无锡市科技发展计划(K20221051)。

摘　　要：体心立方(Body Centered Cubic,BCC)点阵结构具有优异的力学性能,然而节点处的应力集中现象限制了其力学性能的进一步发展。目前多采用添加球形节点或变截面支柱的方法来缓解节点应力集中,实现点阵结构的强化设计,但缺乏节点与支柱体积比对强化效果影响的研究。基于三角函数削减的新型变截面支柱,设计变截面体心立方(Variable Cross-section BCC,VC-BCC)点阵结构,并通过支柱的直接相连实现动态节点设计,以探究最佳的节点与支柱体积比。对VC-BCC结构体积进行理论公式估算,同时基于铁木辛柯梁模型,对VC-BCC结构的等效弹性模量进行理论分析,以等截面等效的方法建立简化模型。对不同节点支柱占比的VC-BCC结构进行了有限元仿真分析,通过选区激光熔融技术制造点阵试件进行准静态压缩试验。结果表明,理论计算与仿真分析相差较小,VC-BCC结构最大应力显著降低,且等效屈服强度提升明显。在所有分析中变截面参数为0.6的VC-BCC结构均表现优异,整体力学性能最佳。Body centered cubic(BCC)structure has excellent mechanical properties,but the stress concentration phenomenon at the nodes limits its further development in mechanical properties.At present,the method of adding spherical nodes or variable cross-section pillars is commonly used to alleviate stress concentration at nodes and achieve strengthening design of lattice structures,but there is a lack of research on the influence of the volume ratio of nodes to pillars on the strengthening effect.A new type of variable cross-section pillar based on trigonometric function reduction is designed,and a variable cross-section body centered cubic lattice(VC-BCC)lattice is designed.Dynamic node design is achieved by directly connecting the pillars to explore the optimal node to pillar volume ratio.Theoretical formula estimation of the volume of VCBCC lattice is carried out,and based on the Timoshenko beam model,the equivalent elastic modulus of VC-BCC lattice is theoretically analyzed.A simplified model is established using the method of equivalent cross-section.Finite element simulation analysis was conducted on VC-BCC lattice with different proportions of node pillars,and lattice specimens were manufactured using selective laser melting technology for quasi-static compression testing.The experimental results show that there is little difference between theoretical calculations and simulation analysis.The maximum stress of the VC-BCC lattice structure is significantly reduced,and the equivalent yield strength is significantly improved.In all analyses,the VC-BCC lattice structure with a variable cross-sectional parameter of 0.6 exhibited excellent performance and had the best overall mechanical properties.

关 键 词：节点强化 点阵结构 体心立方 有限元仿真 选区激光熔融 

分 类 号：TP140[自动化与计算机技术—控制理论与控制工程]