Date of Defense
27-10-2025 1:00 PM
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
Dr.Waleed Ahmed
Keywords
Multi-layer, additive manufacturing, energy absorption
Abstract
This study explores the use of additive manufacturing (AM) technology to create sandwich composite structures, focusing on the manufacturing process, testing, and anticipated impact. The rising cost of manufacturing prototypes using conventional methods has led to the exploration of 3D printing as a viable alternative. The research problem addresses the challenges in manufacturing sandwich composites and the need for automation across the civil, mechanical, aerospace, and aviation industries. The study aims to investigate 3D-printed sandwich composite structures and compare experimental, finite-element analysis, and theoretical results. The proposed methodology includes preparing a CAD model with five different core infill patterns (Cross 3D, Honeycomb, Lines, Gyroid, and Grid) and three core infill percentages (100%, 40%, and 20%). For the face sheets, seven materials were selected for testing. In addition, 3D printing the specimen, inspection, conducting finite element analysis, preparing the specimen for testing, performing a 3-point bending test, data collection, and theoretical calculations. Seventy-seven samples were tested, and it was concluded that as TPU core density decreases from 100% to 20%, the structural response transitions from face-dominated peak strength to core-controlled energy absorption. Grid and Line infill achieve the highest load transfer and stable plateaus at moderate densities. PET and PA-GF faces deliver the most efficient energy absorption. Experimental results align with theoretical and FEA trends but show slight discrepancies due to interface slip and delamination. Overall, optimizing face-core bonding and selecting infill patterns based on load or energy absorption requirements can significantly enhance performance efficiency in lightweight structural designs.
Included in
HYBRID MULTI-LAYER SANDWICH BEAMS USING 3D PRINTING TECHNOLOGY WITH ENERGY ABSORPTION FEATURES
F1-1043
This study explores the use of additive manufacturing (AM) technology to create sandwich composite structures, focusing on the manufacturing process, testing, and anticipated impact. The rising cost of manufacturing prototypes using conventional methods has led to the exploration of 3D printing as a viable alternative. The research problem addresses the challenges in manufacturing sandwich composites and the need for automation across the civil, mechanical, aerospace, and aviation industries. The study aims to investigate 3D-printed sandwich composite structures and compare experimental, finite-element analysis, and theoretical results. The proposed methodology includes preparing a CAD model with five different core infill patterns (Cross 3D, Honeycomb, Lines, Gyroid, and Grid) and three core infill percentages (100%, 40%, and 20%). For the face sheets, seven materials were selected for testing. In addition, 3D printing the specimen, inspection, conducting finite element analysis, preparing the specimen for testing, performing a 3-point bending test, data collection, and theoretical calculations. Seventy-seven samples were tested, and it was concluded that as TPU core density decreases from 100% to 20%, the structural response transitions from face-dominated peak strength to core-controlled energy absorption. Grid and Line infill achieve the highest load transfer and stable plateaus at moderate densities. PET and PA-GF faces deliver the most efficient energy absorption. Experimental results align with theoretical and FEA trends but show slight discrepancies due to interface slip and delamination. Overall, optimizing face-core bonding and selecting infill patterns based on load or energy absorption requirements can significantly enhance performance efficiency in lightweight structural designs.