Analysis of 3D printed honeycomb sandwich structures under three point bending

• Main Author: Illyas Dzulkaflee
• Other Authors: Yeong Wai Yee
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering
• Online Access: http://hdl.handle.net/10356/67704
• Institution: Nanyang Technological University

The aim of this project is to study the structural behaviour of hexagonal honeycomb sandwich structure of three different facesheet configurations that is subjected under three point bending. The three facesheet configurations are the single-layered, multi-layered and the unidirectional-layered facesheet. Additive Manufacturing multi-materials inkjet 3D printing is used to fabricate both honeycomb core and facesheets. The three facesheets configurations were fabricated according to their respective combinations of rigid plastic and rubbery material. This project consists of three main parts; the fabrication of honeycomb sandwich structures, experimental three point bending test on honeycomb sandwich specimens and the use of finite element method to compare and validate the experimental results. Tensile test were also conducted on the materials involved in the fabrication of the sandwich structures to determine the mechanical properties of each material to be defined as material assignment in finite element analysis. Five specimens of each configurations undergo three point bending test using Shimadzu Universal testing machine. All except two specimens failed due to debonding of core and facesheet. The other two specimens failed due to core shearing. Results from experimental tests were discussed and to be used to validate the finite element results Finite Element Analysis (FEA) software ABAQUS version 6.14 was used to model honeycomb sandwich beam of the three configurations undergoing the three point bending test. The FE results showed there is variation with the experimental results. However, the simulation results agreed with the experimental results that honeycomb sandwich with single-layered facesheet has higher bending stiffness as compared with the other two.