Date of Defense
21-8-2025 12:00 AM
Location
F1-1043
Document Type
Thesis Defense
Degree Name
Master of Science in Mechanical Engineering (MSME)
College
COE
Department
Mechanical and Aerospace Engineering
First Advisor
Prof. Abdel Hamid Ismail Mourad
Keywords
Material Extrusion, 3D Printing, Short-fiber reinforced polypropylene, Gyroid, Lattice Structure, Double Gyroid, Mechanical Performance.
Abstract
This study explores the enhanced compressive behavior of 3D-printed single and double gyroid solid-networks lattices. Where the double gyroids are constructed from two intertwined single gyroid structures. These structures were designed by nTop implicit modeling tool and then fabricated by material extrusion additive manufacturing method at optimized printing parameters, including optimized nozzle temperature and raster angle. The main objective of this study is to reveal the compressive behavior of the novel double gyroid lattice structure and then to tailor its response through variable gyroid heights. Standard polymer tests were performed, considering thermogravimetric analysis, to confirm the thermal stability of the printed material and to reveal the initial degradation temperature of the filament, which was found to be around 277°C. The compression results demonstrate that increasing the relative density enhances both the mechanical properties and failure resistance in both architectures. For instance, a 32% increase in relative density from 0.5 to 0.66 for double gyroids led to a 102% increase in peak load. Distinct failure modes were observed: single gyroid structures exhibited shear failure at approximately 45°, while double gyroid structures failed via densification, showing a more gradual failure behavior. This unique failure behavior offers a more gradual collapse mechanism and potential controllability through gyroids’ height variation. Despite that, double gyroid structures achieving lower peak loads than single gyroid lattices at equivalent relative densities. This research provides valuable insights into the complex interplay between relative density, architecture, and failure in 3D-printed cellular structures, guiding the design and optimization of these materials for diverse applications such as aerospace and automotive engineering, where weight reduction is crucial.
Included in
3D PRINTING OF SHORT FIBER REINFORCED POLYPROPYLENE: NOVEL LATTICE ARCHITUCTURE AND MATERIAL CHARACTERIZATION
F1-1043
This study explores the enhanced compressive behavior of 3D-printed single and double gyroid solid-networks lattices. Where the double gyroids are constructed from two intertwined single gyroid structures. These structures were designed by nTop implicit modeling tool and then fabricated by material extrusion additive manufacturing method at optimized printing parameters, including optimized nozzle temperature and raster angle. The main objective of this study is to reveal the compressive behavior of the novel double gyroid lattice structure and then to tailor its response through variable gyroid heights. Standard polymer tests were performed, considering thermogravimetric analysis, to confirm the thermal stability of the printed material and to reveal the initial degradation temperature of the filament, which was found to be around 277°C. The compression results demonstrate that increasing the relative density enhances both the mechanical properties and failure resistance in both architectures. For instance, a 32% increase in relative density from 0.5 to 0.66 for double gyroids led to a 102% increase in peak load. Distinct failure modes were observed: single gyroid structures exhibited shear failure at approximately 45°, while double gyroid structures failed via densification, showing a more gradual failure behavior. This unique failure behavior offers a more gradual collapse mechanism and potential controllability through gyroids’ height variation. Despite that, double gyroid structures achieving lower peak loads than single gyroid lattices at equivalent relative densities. This research provides valuable insights into the complex interplay between relative density, architecture, and failure in 3D-printed cellular structures, guiding the design and optimization of these materials for diverse applications such as aerospace and automotive engineering, where weight reduction is crucial.