Publication Date
2017
Document Type
Thesis
Committee Members
Ahsan Mian (Advisor), Joseph Slater (Committee Member), Raghavan Srinivasan (Committee Member)
Degree Name
Master of Science in Mechanical Engineering (MSME)
Abstract
Sandwich panel structures are widely used in aerospace, marine, and automotive applications because of their high flexural stiffness, strength-to-weight ratio, good vibration damping, and low through-thickness thermal conductivity. These structures consist of solid face sheets and low-density cellular core structures, which are often based upon honeycomb topologies. The recent progress of additive manufacturing (AM) (popularly known as 3D printing) processes has allowed lattice configurations to be designed with improved thermal-mechanical properties. The aim of this work is to design and print lattice truss structures (LTS) keeping in mind the flexible nature of AM. Several 3D printed core structures were created using polymeric material and were tested under low-velocity impact loads. Different unit-cell configurations were compared to aluminum honeycomb cores that are tested under the same conditions. An impact machine was designed and fabricated following the ASTM D7136 Standard to correctly capture the impact response. The absorption energy as well as the failure mechanisms of lattice cells under such loads are investigated. The differences in energy-absorption capabilities were captured by integrating the load-displacement curve found from the impact response. Similar manufacturing and sandwich-panel-fabrication processes must be used to accurately compare the impact responses. It is observed that selective placement of vertical support struts in the unit-cell results in an increase in the absorption energy of the sandwich panels. Other unit-cell configurations can be designed with different arrangements of vertical struts into the well-known body centered cubic (BCC) LTS for further improvements in absorption energy capabilities.
Page Count
125
Department or Program
Department of Mechanical and Materials Engineering
Year Degree Awarded
2017
Copyright
Copyright 2017, all rights reserved. My ETD will be available under the "Fair Use" terms of copyright law.
