Energy absorption and compression behaviour of polymeric 3D printed lattice structures - experimental and numerical study

摘要

Worldwide advance technologies, innovations and development in field of design and manufacturing have expended functionality of structures at small scale to fulfil requirement of behavior of material at micro level. Purpose behind this scope is to produce light weight structure by utilizing minimum material, cost and achieving maximum mechanical behavior of material. In order to achieve this approach, combination of experimental and numerical set up developed to focus on the effect of additive manufactured polymeric micro-lattice structures geometry over energy absorption capability, deformation and compression behavior. In this work, the energy absorption characteristics of three different polymeric lattice topologies i.e.uniform body centered cubic (UBCC), uniform body centered cubic reinforced in z- axis (UBCCz), and graded body centered cubic (GBCC) were considered, manufactured by using digit light processing (DLP) 3D printing technique. The quasistatic compression test was performed to study energy absorption capability, compression behavior, failure modes and relation between load and displacement. Although dimensions and mass of all polymeric lattice blocks were same but effect of cell architecture on mechanical behavior of lattice was significant. The mechanical behavior and deformationof GBCC is different from uniform counterparts. Densification rate in upper layers of GBCC having smaller diameter occurred earlier than next lower layer having larger diameter. Energy absorption capability in UBCCz is muchhigher than UBCC and GBCC. Large displacement deformation occurred in UBCC due to cell space. In UBCCz additional strut as reinforcement in z-direction acted as stress bearing member and improved its stress bearing capability. Moreover, higher elastic modulus and stiffnessin UBCCzis observed than other two cell topologies. In the end, finite element simulations were carried out using LS DYNA-3D to validate the result and comparing it with experimental data.