Improving Mechanical Properties and Energy Absorption of Additive Manufacturing Lattice Structure by Struts’Node Strengthening  

作　　者：Dongming Li Ruixian Qin Jianxin Xu Junxian Zhou Bingzhi Chen 

机构地区：[1]School of Mechanical Engineering,Dalian Jiaotong University,Dalian,116028,China [2]School of Locomotive and Rolling Stock Engineering,Dalian Jiaotong University,Dalian,116028,China [3]School of Materials Science and Engineering,Dalian Jiaotong University,Dalian,116028,China

出　　处：《Acta Mechanica Solida Sinica》2022年第6期1004-1020,共17页固体力学学报（英文版）

基　　金：supported by the Science and Technology National Research and Development Plan of China National Railway Corporation (N2020J027);the Science and Technology Innovation Fund Plan of Dalian (2019J11CY017).

摘　　要：The lattice structure has unique performance and superior deformation behavior,which effectively stimulates the design and application of new lattice structures.The development of additive manufacturing technology makes it easy and efficient to manufacture complex lattice structures.However,it has been found that excessively high stress concentration exists at the struts’nodes during the compression of lattice structure.Therefore,three node strengthening strategies were proposed to reduce stress concentration,which were adding fillet at nodes,using circular arc transition and changing the angle of nodes.Firstly,lattice structures were manufactured by selective laser melting technique.The surface morphology of the lattice structures was observed by scanning electron microscopy.Then,the stress distribution and deformation mechanism of different lattice structures were investigated by quasi-static compression experiments and numerical simulation.Finally,the Gibson–Ashby model was adopted to predict lattice structures’modulus and strength.And the energy absorptions of different structures were compared.The results revealed that the deformation mode of the optimized structures changed from shear failure to layer-by-layer collapse.Compared with the hourglass lattice structure and gradient lattice structure,the mechanical properties of curve lattice structure were improved the most.

关 键 词：Node strengthening Stress concentration Lattice structure Selective laser melting Deformation mode 

分 类 号：O735[理学—晶体学]