Lunar Manufacturing Systems And The Role Of Additive Recycling Technologies, Camille A. Newman

Honors Theses

Renewed international interest in sustained lunar exploration has created a growing demand for technologies to support long-duration space exploration. Part of the recent Artemis missions and the Moon to Mars initiative is to improve key mission capabilities and fill critical gaps necessary to sustain lunar habitation. Waste management, recycling systems, and manufacturing systems have been identified as critical technologies that need further development before a sustained mission is possible. This thesis explores the feasibility of an additive manufacturing and recycling system designed to process plastic waste generated during extended lunar habitation. Initial research focused on existing manufacturing and recycling technologies …

Additive Manufacturing Of Ti-Ni Based Ternary Shape Memory Alloys, Yitao Chen, Frank Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metal additive manufacturing has become a powerful tool to develop customized metal alloys and to discover more advanced properties for novel extended applications. Ti-Ni based shape memory alloy is a group of intriguing smart functional materials, and adding a small amount of a third element can promote and induce more attractive functions. Due to the difficulty in traditional processing and the unique feature of material flexibility of in-situ alloying in additive manufacturing processes, not only Ti-Ni binary shape memory alloys but also Ti-Ni-X ternary shape memory alloys can be developed, manufactured, and investigated in-depth by additive manufacturing. This paper provides …

Field-Assisted Post-Processing Of Cold-Sprayed Pure Copper, Alan Hensley

Theses and Dissertations--Mechanical and Aerospace Engineering

The properties of materials processed through cold spray, and many other AM processes, are non-uniform and unpredictable. In most cases, post-processing is required to achieve desired properties and better uniformity. In cold spray, the typical method is an annealing heat treatment (AHT), which can improve bond strength, reduce porosity, and restore ductility, among other effects. AHT alone, however, is unable to completely remedy any of the unfavorable properties. In addition, long treatments at high temperatures are often needed for satisfactory results. This increases energy consumption and extends production times for products made by the process. For these reasons, numerous investigations …

Fused Filament Fabrication Additive Manufacturing Of 17-4 Ph Stainless Steel: Process–Structure–Property Relationships In Magnetic Materials, Maanav Patel

Theses and Dissertations

Additive manufacturing (AM) enables the fabrication of complex metallic components through layer-by-layer processing directly from digital models. Among AM techniques, material extrusion–based processes such as fused filament fabrication (FFF) provide an accessible method for producing metal parts using filament feedstocks composed of metal powders and polymer binders. When applied to precipitation-hardening stainless steels such as 17-4 PH, the processing route and heat treatments can influence the resulting microstructure and functional properties. This work investigates the magnetic behavior of 17-4 PH stainless steel fabricated using FFF and evaluates how heat treatment conditions influence measured magnetic properties. Samples were produced and analyzed …

The Effect Of Scanning Strategy And Build Conditions On The Residual Stress Of A Ded System With Realistic Clad Geometry, Christopher Matthew Roeder

Graduate Research Theses & Dissertations

Direct Energy Deposition (DED) is a leading metal additive manufacturing method for fabricating complex parts. However, the high thermal gradients during the process, along with their effects on thermal expansion and shrinkage during heating and cooling cycles, result in significant residual stress that imposes substantial limitations on the building process. These stresses can lead to warpage, cracking, and a reduction in overall mechanical performance, challenges that must be addressed in most manufacturing industries. While scanning patterns and clad geometry have often been studied independently, their interaction may provide deeper insights into the causes and effects of these operating conditions on …

Mechanical Behavior Of Additively Manufactured Ti-6al-4v Eli Parts: Effects Of Laser Parameter Selection, Samuel Lopez

UNF Graduate Theses and Dissertations

Additive manufacturing (AM) of TI-6AL‑4V Extra‑Low Interstitial (ELI) enables complex geometries for fatigue‑critical medical device applications, yet fatigue performance remains sensitive to process‑induced defects. This work investigates the effect of laser process parameter selection on the microstructure, mechanical properties, and fatigue behavior of TI- 6AL‑4V ELI fabricated via laser powder bed fusion (L‑PBF) using a Renishaw RenAM system. The influence of laser parameters was isolated by holding powder chemistry, build orientation, scan strategy, sub‑transus annealing, and post‑processing constant between a non‑optimized baseline and an optimized parameter set selected based on tensile performance.

Optical microscopy showed the optimized condition exhibited improved …

Recreating Fiber Recruitment With Fiber Recruitment Using Additive Manufacturing, Natalia D. Mciver

Biomedical Engineering ETDs

Injured ligaments are often repaired with tendon grafts which may over or under constrain the joint; there is a need for an artificial graft option with the mechanical properties of a native ligament. Crimped fibers within ligaments allow for recruitment which means the viscoelastic properties of stress relaxation and creep are not inversely related. A feasibility study using ACLs and large-scale crimp models to study viscoelasticity, led to an in-depth analysis of the scapholunate interosseous ligament. Using the Modified Kelvin spring-dashpot model, for describing viscoelasticity with a variable stiffness property (time dependent fiber recruitment), we defined the relationship between creep …

Powder Degradation Analysis In Reused Pure Tungsten For Electron Beam Melting (Ebm), Hernan Valenzuela

Open Access Theses & Dissertations

Additive manufacturing (AM) enables unparalleled design freedom and geometric complexity, driving its adoption in aerospace and medical fields. A major advantage of metal powder AM technologies, such as Electron Beam Melting (EBM), is its ability to reuse unused metal powder, reducing material waste and costs. However, reusing powder repeatedly alters its properties, affecting the final product. Despite its significance, research on powder degradation remains limited, primarily focusing on alloys like Ti-6Al-4V. This thesis investigates the degradation of pure tungsten powder reused over multiple Electron Beam Melting (EBM) cycles. A literature review revealed general powder-reuse mechanisms across additive manufacturing (AM) technologies …

Comparison Of Ti-6al-4v Powder And Bulk Specimen Properties Across Manufacturers In Laser Powder-Blown Ded, Alejandro Javier Hernandez

Open Access Theses & Dissertations

The investigation and comparison of 4 different Ti64 powder feedstocks from 3 different manufacturers was done to determine if the quality of the powder had a profound effect on the properties of the bulk specimens despite using the same processing parameters. The characteristics of the powder observed are the atomization process used, particle size distribution, flowability, and its density. The Ti64 printing parameters for directed energy deposition that were kept consistent were the feed rate, scanning speed, and laser power. Coupons with varying build angles (0-30°) were printed to measure the impact of overhangs on bulk specimen properties (ultimate tensile …

Advancing Aerospace Materials: 3d Printing Of Fiber Reinforced Cyanate Ester Ipns And Uhtcmcs, Saqlain Zaman

Open Access Theses & Dissertations

Additive manufacturing (AM) is rapidly reshaping the landscape of advanced materials for aerospace, hypersonic, and extreme-environment systems. However, AM of high-temperature polymer and ceramic composites, especially those reinforced with continuous or aligned fibers, remains limited by challenges in rheological control, in situ fiber impregnation, curing compatibility, densification, and achieving directional multifunctional properties. This dissertation advances a unified Direct Ink Writing (DIW) framework enabling the processing of architected, high-performance composite materials across polymer and ceramic systems. Three research thrusts collectively establish scalable pathways for fabricating fiber-reinforced cyanate ester interpenetrating polymer networks (IPNs) and ultra-high-temperature ceramic matrix composites (UHTCMCs). First, a dual-curable …

Experimental And Numerical Study On The Influence Of Carbon Fiber Reinforcement On The In-Plane Compressive Properties Of 3d Printed Hexagonal Honeycomb Core Structures, Deon Wallace

All Theses

There is difficulty with numerically replicating the behavior of composite honeycomb core structures numerically due to the trouble of gathering material properties from a hollow structure. Also, complex part geometries and carbon fiber reinforcement strategies can lead to unwanted structural weaknesses and variance in material properties that may not be reflected in numerical analysis when the part is additively manufactured. In this study, edgewise compressive testing is used to characterize the mechanical behavior and performance characteristics of these structures. The experimental results indicate an increase in the Young’s moduli of the honeycomb core structures as carbon fiber concentration increases. However, …

Cold Spray On Fiber Reinforced Polymer Substrates For Composite Repair And Tooling Applications, Patrick Allen Bailey

Theses and Dissertations

Cold Spray technology was first developed in the 1980’s and is an additive manufacturing and repair technique. It works by heating a pressurized carrier gas upwards of 600 °C and inserting metal particles downstream such that when they impact a substrate, the energy transformation causes plastic deformation of the particles. This thesis presents a use case for metal and polymer CS powder on fiber reinforced and fused filament fabrication polymer substrates. The state of the art for CS discusses the most up-to-date research within the field, and where new investigations are required. This research investigates the required process parameters to …

Anisotropic Residual Stress Measurements In Additively Manufactured 316 Stainless Steel Parts, Rajeshree Varma, Donovan Stumpf, Paul R. Mort

15th International Conference on Shot Peening

Additive manufacturing (AM) using laser powder bed fusion (L-PBF) is increasingly used to produce complex parts for industries like aerospace and medical devices. The intrinsic characteristics of AM – layer-wise deposition and rapid thermal cycling – generate significant, anisotropic, residual stresses that can compromise part quality and performance. Recent studies highlight how these stresses are strongly influenced by process parameters and build orientation. X-ray diffraction (XRD) techniques, including sin²ψ and advanced two-dimensional approaches, have become the preferred methods for non-destructive, directionally resolved measurement of residual stress in AM metals. This review surveys advancements in XRD residual stress methods with a …

Enhancing High Cycle Fatigue Perfomance Of Electron Beam Melted Ti6al4v: A Study On Shot Peening And Hot Isostatic Pressing, Naghmeh M. Mojib, Dwayne D. Arola, Ramulu Mamidala

15th International Conference on Shot Peening

The qualification of electron beam powder bed fusion (PBF-EB) for safety-critical applications is hindered by variability in high cycle fatigue performance, largely due to surface roughness and internal defects. While Hot Isostatic Pressing (HIP) effectively reduces internal porosity, it does not address surface-initiated fatigue failures. This study investigated the combined effects of HIP and shot peening on enhancing the fatigue performance of PBF-EB Ti6Al4V. Over 50 specimens, including both vertical and horizontal build orientations, underwent high cycle fatigue testing per ASTM E466. X-Ray computed tomography confirmed decrease in defect distribution following HIP, while shot peening resulted in a more uniform …

Microstructure And Defects Of Aa6061 In The Laser Powder Bed Fusion Additive Manufacturing, Sivaji Karna

Theses and Dissertations

AA6061 is a widely used aluminum alloy known for its excellent thermal conductivity, strength, and corrosion resistance. However, its application in Laser Powder Bed Fusion (LPBF) additive manufacturing is restricted by solidification cracking and porosity. This study examines defect formation, microstructural evolution, and precipitate behavior in AA6061 processed under various LPBF conditions, including room temperature and heated substrates (500°C), as well as pulsed wave laser configurations. Microstructural characterization was conducted using optical microscopy, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDS) and electron backscatter diffraction (EBSD), and transmission electron microscopy (TEM).

A maximum relative density of 99.17% was …

In-Situ Defect Detection In Selective Laser Melting Using Convolutional Neural Networks, Ethan Gaigalas

Master's Theses

This thesis develops and trains a convolutional neural network (CNN) to classify defects in metal parts produced by selective laser melting (SLM) using acoustic emission (AE) data. The model successfully identified porosity and standard build layers with high accuracy but consistently struggled to classify lack of fusion (LOF) defects, regardless of input type, normalization, or class count. These results suggest that while AE signals contain distinguishable features for certain defect types, LOF signals may be too subtle or inconsistent for reliable detection. The study addresses the ongoing challenge of in-situ quality monitoring in metal additive manufacturing, where defects like cracks, …

Thermal Modeling Techniques For Additively Manufactured Porous Metals, Lucas D. Rambo

Master's Theses

Advances in additive manufacturing have enabled the creation of metallic components with tailored porosity, offering design flexibility for thermal, structural, and fluid transport applications. This thesis investigates the effective thermal conductivity (ETC) of porous Inconel 625 (IN625) and Inconel-ceramic composites (IN625-RAM2) fabricated by Laser Powder Bed Fusion (LPBF) using Elementum 3D’s PermiAM technology. Experimental measurements of thermal conductivity using the laser flash method are compared to numerical models built from micro-computed tomography data. Simulations were performed using both finite element (FE) and finite volume (FV) methods to evaluate thermal transport in real microstructures. The study investigates the effects of micro- …

Autonomous Defect Detection In Additive Manufacturing, John Samuel Poindexter Iv

Theses and Dissertations

Additive manufacturing (AM) is the process of creating a product by applying layers of material to build up to the final product. AM has revolutionized the field of manufacturing and has allowed more complex products to be manufactured at reasonable cost, quicker manufacturing time, and optimized material usage. Traditional forms of manufacturing were based on subtractive manufacturing, where by a product would be created by removing material from its source. AM is a new manufacturing process and faces significant challenges when it comes to manufacturing due to defects. Defects can vary from type and severity and can overall weaken or …

Exploring Metal Additive Manufacturing In Martian Atmospheric Environments, Zane Mebruer

Mechanical Engineering Undergraduate Honors Theses

On-surface manufacturing is key to the success of a planetary colonization, especially that of Mars. However, traditional subtractive manufacturing processes are equipment, energy, and material intensive, meaning novel additive manufacturing (AM) processes must be pursued for this end. Selective laser melting, one of the most effective and versatile AM methods, would be incredibly beneficial to a Martian mission but requires an artificial argon atmosphere to create effective parts. The purpose of this study was to examine if carbon dioxide, the gas that makes up over 95% of Mars’ surface atmosphere, would be a sufficient substitute for argon in SLM fabrication. …

Tailoring Functional And Sensing Properties Of Polymer-Ceramic Composites Via 3d Printing, Alexis Lopez

Open Access Theses & Dissertations

Section 1.1. Abstract This chapter investigates the use of direct ink write (DIW) additive manufacturing to control grain orientation in non-toxic barium titanate (BTO) ceramics by blending spherical and platelet-shaped particles in the ink. A series of inks containing 0–40 wt.% BTO platelets were formulated with poly(vinyl alcohol), polyethylene glycol, poly(acrylic acid-co-maleic acid), and ammonium hydroxide to ensure printability and homogeneous dispersion. Cylindrical specimens (20 mm × 3 mm) were printed using a Hyrel 30M DIW system and subjected to de-binding (650 °C, 2 h) followed by a two-step sintering schedule (T₁: 1200–1350 °C; T₂: 700–850 °C; 24 h dwell). …

3d Printed Living Hinges In Deployable Origami Structures, Davis Wing, Robert J. Lang, Spencer Magleby, Larry Howell

Student Works

Origami-based geometries are often difficult to prototype and construct. Although methods exist for creating surrogate folds in many materials, doing so often requires multiple manufacturing steps. While engineers studying foldable models can use single-material additive manufacturing to construct living hinges in their models, current techniques are limited. We present an approach for generating living hinges in stowed, deployable mechanisms using single-material 3D printing. This approach enables new models to be constructed with accurate geometry and kinematics in a single print and with no further manufacturing necessary beyond an initial folding step. Additionally, by printing deployable structures in their stowed form, …

Deployable Origami Structure, David J. Garcia, Robert Bettinger

AFIT Patents

The present invention relates to deployable origami structures and methods of making and using same. Such deployable origami structures can be folded into a compact state utilizing origami, yet easily deployed as the structures comprise pseudo-elastic connectors. Additive manufacturing techniques can be used to make such deployable origami structures as such techniques can lower cost and structure weight.

A Computational Fluid Dynamics Approach To Analyze The Virtual Impactor In Pneumatic Aerosol Jet Printing, Akashita Sareen

Theses, Dissertations and Capstones

Aerosol jet printing (AJP) is a 3D printing, advanced manufacturing process that generates an aerosol mist appropriate for fine printing small, low-volume electronic parts. The pneumatic aerosol jet printing technology’s virtual impactor is the focus of this study. In this technology, high velocity nitrogen gas aerosolizes various inks in the atomizer. The aerosolized stream of ink is then transported to a virtual impactor (VI) to become dense and concentrated as it begins to enter the deposition head for high precision electronics printing. AJP faces challenges in large-scale adoption due to challenges related to overspray, instability, ink clogging etc. There is …

Improving The Reliability Of Parts Produced Via Laser Powder Bed Fusion Through A Data-Driven Geometry Optimization Methodology, Federico Venturi

Mechanical and Aerospace Engineering Dissertations - Archive

This research aims to qualify the effect of design geometry on quality metrics of additively manufactured (AM) components that define reliability. Through the use of a novel methodology to characterize these quality metrics, AM components are inspected for the presence of defects such as surface roughness notches and porosity. These directly hinder the high-cycle fatigue characteristics demonstrated through the Kitagawa-Takahashi diagram and the El-Haddad model. By demonstrating the effect of geometry through a designed experiment and the adoption of the Murakami square root area parameter and Arola-Ramulu model, the improvement to fatigue life can be quantified. Incorporating this data into …

Experimental And Numerical Modelling-Based Optimization Of Additive Manufacturing Processes, Vishnu V. Ganesan

Mechanical and Aerospace Engineering Dissertations - Archive

ABSTRACT

Experimental and Numerical Modeling-Based Optimization of Additive Manufacturing Processes

Vishnu V Ganesan, Ph.D.

The University of Texas at Arlington, 2025

Supervising Professor: Dr. Ankur Jain

Experimental and numerical modeling play a pivotal role in advancing additive manufacturing technologies by enabling a deeper understanding of complex, multi-physics processes that govern part quality, performance, and reliability. These manufacturing techniques—ranging from Powder Bed Fusion (PBF) and Material Extrusion (MEX) to Automated Fiber Placement (AFP)—involve tightly coupled thermal, mechanical, and material phenomena that are challenging to capture through empirical observation alone. Experimental methods offer critical validation and insights into real-world behavior, while numerical …

Machine Learning Approach For Defect Prediction In Metal 3d Printing For Aerospace Applications, Yerlik Gabdulla, Md Hazrat Ali, Frank Liou, Essam Shehab

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Additive manufacturing (AM) has revolutionized the aerospace industry by enabling the production of lightweight and high-strength components, such as aerospace engine components and structural elements. The ability to create complex geometries and reduce material waste is particularly beneficial for aerospace applications, where performance and weight reduction are paramount. However, ensuring the quality and reliability of these components remains a challenge, particularly in mass production, which is related to material quality, expensive processes, and longer computational times than conventional manufacturing methods. This paper proposes an approach utilizing a Decision Tree Classification Machine Learning Algorithm to predict the possibility of defect occurrence …

Transient Thermal Finite Element Simulation For Process Modeling In Wire Arc Additive Manufacturing, Satya Sai Kumar Pilli

Dissertations, Master's Theses and Master's Reports

This thesis presents the development of a transient thermal framework for Wire Arc Additive Manufacturing (WAAM) created using ANSYS Workbench. This study aims to understand the inherent properties and thermal behavior of WAAM by using the Finite Element (FE) simulation technique to reduce the need for experiments. Specifically, the transient thermal WAAM simulation framework uses the heat source Goldak model to understand the thermal behavior for a given voltage, initial temperature, and travel speed during the process to predict process temperature. The outcomes of this thesis aim to significantly decrease material waste and repetitive experiments and accelerate production process design …

Design And Deployment Of A Compact Rov For Deep-Sea Research And Exploration, Joshua F. Wood

Open Access Master's Theses

The scientific community has utilized unmanned underwater vehicles for ocean exploration since the mid-twentieth century, resulting in a well-cultivated and ever-changing discipline of ocean technology. The deep-sea environment, specifically, presents unique and harsh criteria due to the increased pressure found at depth and the vehicle components necessary to overcome it. The size and weight of underwater vehicles typically increase as operational depth increases, resulting in physically large systems with high operational costs to accommodate deep-sea research. This project first characterized the effect of length and diameter on carbon fiber pressure housing’s depth tolerance. It then leveraged this data to reduce …

Fluid Pathways For Enhanced Mass Transfer In The Micro Regime: Applications In Novel Pumpless Redox Flow Cell And Zinc Finger Protein-Based Dna Detection, Shaikh Al Mahmud Bhuiyan

Theses and Dissertations--Mechanical and Aerospace Engineering

Precise fluid transport through microscale geometries can help optimize electrochemical and biochemical processes by maximizing the mass transfer rate of reactants. By introducing intricate structural features inside microchannels, it is possible to manipulate the fluid motion and direct the flow towards any surface of interest. In this study, we have demonstrated that rationally designed fluid pathways can improve the performance of electrochemical and biochemical systems.

The emergence of additive manufacturing has enabled rapid fabrication of robust structures with intricate features to guide fluid motion. However, their application in nonaqueous electrochemical systems has been limited due to their interaction with organic …

Effect Of Build Orientation On Tensile Properties And Fractography Of Additive Manufactured Inconel 718 Alloy, Ajay Kumar Maurya, Amit Kumar, Swarnambuj Suman

ASEAN Journal on Science and Technology for Development

The additive manufacturing (AM) technique “Direct Metal Laser Sintering (DMLS)” is used to create 3D objects directly from 3D design data. A lightweight and complexity-free part without any expensive tooling can be fabricated easily using this method, but it is still challenging to achieve the desired mechanical strength from AM parts, as the mechanical properties of AM-produced parts vary with orientation, scan strategy, and process parameters. Inconel 718 alloy is most commonly utilized in the aerospace and automotive industries, because of its high resistance to corrosion and excellent mechanical qualities. This work presents a study to investigate the orientation-based mechanical …