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Articles 1 - 30 of 39
Full-Text Articles in Engineering
Residual Stress Generation In Additive Manufacturing Of Complex Lattice Geometries, Katie Bruggeman, Nathan Klingbeil, Anthony N. Palazotto
Residual Stress Generation In Additive Manufacturing Of Complex Lattice Geometries, Katie Bruggeman, Nathan Klingbeil, Anthony N. Palazotto
Faculty Publications
Residual stresses developed during additive manufacturing (AM) can influence the mechanical performance of structural components in their intended applications. In this study, thermomechanical residual stress simulations of the laser powder bed fusion (LPBF) process are conducted for both simplified (plate and cube-shaped) geometries as well as five complex lattice geometries fabricated with Inconel 718. These simulations are conducted with the commercial software package Simufact Additive©, which uses a nonlinear finite element analysis and layer-by-layer averaging approach in determining residual stresses. To verify the efficacy of the Simufact Additive© simulations, numerical results for the plate and cube-shape geometries are analyzed for …
Fast-, Light-Cured Scintillating Plastic For 3d-Printing Applications, Brian G. Frandsen, Michael Febbraro, Thomas Ruland, Theodore W. Stephens, Paul A. Hausladen, Juan J. Manfredi, James E. Bevins
Fast-, Light-Cured Scintillating Plastic For 3d-Printing Applications, Brian G. Frandsen, Michael Febbraro, Thomas Ruland, Theodore W. Stephens, Paul A. Hausladen, Juan J. Manfredi, James E. Bevins
Faculty Publications
Additive manufacturing techniques enable a wide range of possibilities for novel radiation detectors spanning simple to highly complex geometries, multi-material composites, and metamaterials that are either impossible or cost prohibitive to produce using conventional methods. The present work identifies a set of promising formulations of photocurable scintillator resins capable of neutron-gamma pulse shape discrimination (PSD) to support the additive manufacturing of fast neutron detectors. The development of these resins utilizes a step-by-step, trial-and-error approach to identify different monomer and cross-linker combinations that meet the requirements for 3D printing followed by a 2-level factorial parameter study to optimize the radiation detection …
Laser Powder Bed Fusion Of Molybdenum And Mo-0.1sic Studied By Positron Annihilation Lifetime Spectroscopy And Electron Backscatter Diffraction Method, Nathan E. Ellsworth, Joshua R. Machacek, Ryan A. Kemnitz, Cayla C. Eckley, Brianna M. Sexton, Joel S. Gearhart, Larry W. Burggraf
Laser Powder Bed Fusion Of Molybdenum And Mo-0.1sic Studied By Positron Annihilation Lifetime Spectroscopy And Electron Backscatter Diffraction Method, Nathan E. Ellsworth, Joshua R. Machacek, Ryan A. Kemnitz, Cayla C. Eckley, Brianna M. Sexton, Joel S. Gearhart, Larry W. Burggraf
Faculty Publications
Positron annihilation lifetime spectroscopy (PALS) has been used for the first time to investigate the microstructure of additively manufactured molybdenum. Despite the wide applicability of positron annihilation spectroscopy techniques to the defect analysis of metals, they have only been used sparingly to monitor the microstructural evolution of additively manufactured metals. Molybdenum and molybdenum with a dilute addition (0.1 wt%) of nano-sized silicon carbide, prepared via laser powder bed fusion (LPBF) at four different scan speeds: 100, 200, 400, and 800 mm/s, were studied by PALS and compared with electron backscatter diffraction analysis. The aim of this study was to clarify …
Influence Of Nano-Sized Sic On The Laser Powder Bed Fusion Of Molybdenum, Nathan E. Ellsworth, Ryan A. Kemnitz, Cayla C. Eckley, Brianna M. Sexton, Cynthia T. Bowers, Joshua R. Machacek, Larry W. Burggraf
Influence Of Nano-Sized Sic On The Laser Powder Bed Fusion Of Molybdenum, Nathan E. Ellsworth, Ryan A. Kemnitz, Cayla C. Eckley, Brianna M. Sexton, Cynthia T. Bowers, Joshua R. Machacek, Larry W. Burggraf
Faculty Publications
Consolidation of pure molybdenum through laser powder bed fusion and other additive manufacturing techniques is complicated by a high melting temperature, thermal conductivity and ductile-to-brittle transition temperature. Nano-sized SiC particles (0.1 wt%) were homogeneously mixed with molybdenum powder and the printing characteristics, chemical composition, microstructure, mechanical properties were compared to pure molybdenum for scan speeds of 100, 200, 400, and 800 mm/s. The addition of SiC improved the optically determined density and flexural strength at 400 mm/s by 92% and 80%, respectively. The oxygen content was reduced by an average of 52% over the four scan speeds analyzed. Two mechanisms …
Mechanical Properties And Tension-Tension Fatigue Behavior Of A Novel Additively Manufactured Polymer Matrix Composite At Room And Elevated Temperature, Grayson M. Harber
Mechanical Properties And Tension-Tension Fatigue Behavior Of A Novel Additively Manufactured Polymer Matrix Composite At Room And Elevated Temperature, Grayson M. Harber
Theses and Dissertations
The tension-tension fatigue behavior of a novel additively manufactured AM carbon fiber reinforced polymer matrix composite was studied. This novel material system consists of T1100 carbon fibers, and a UV photocured resin developed by Continuous Composites and Sartomer. Tensile properties and tension-tension fatigue were investigated for the 090 fiber orientation as well as for the ±45 fiber orientation. Specimens with 0/90 fiber orientation were tested at ambient laboratory temperature 23 °C and at elevated temperature 150 °C, while the specimens with the ±45 fiber orientation were tested only at ambient laboratory temperature. Tension-tension fatigue testing was carried out with a …
Finite Fatigue Life Prediction Of Additively Manufactured Aircraft Engine Turbine Blade With Respect To Internal Defect Size And Location, Daniel G. Miller
Finite Fatigue Life Prediction Of Additively Manufactured Aircraft Engine Turbine Blade With Respect To Internal Defect Size And Location, Daniel G. Miller
Theses and Dissertations
Current fatigue life modeling techniques with respect to defects emphasize the dependence on the defect size with respect to fatigue life, but does not account for the effects of where a defect might be located. This research outlines a process to include defect location into the model analysis for a more precise prediction of the number of cycles to failure and where the finial failure could occur within a component. The focus is on a turbine blade structure using IN718 subjected to a pure vibratory load. The basic model predicts component life using a stress map from the frequency analysis …
Additive Manufacturing Of Molybdenum For High Temperature Structural Applications, Megan L. Bustin
Additive Manufacturing Of Molybdenum For High Temperature Structural Applications, Megan L. Bustin
Theses and Dissertations
This research considered additive manufactured (AM) molybdenum (Mo) and the effect of three variables on microstructure, mechanical properties, and the relationship between the two. Test temperature, laser speed, and shield gas or build atmosphere were varied, and samples tested and analyzed using a three-point bending test, chemical composition, and optical and scanning electron microscopy. The relationship among variables and results using a Design of Experiments was limited compared to the inclusion of every tested sample. Most effects were expected: samples tested at room temperature were brittle without statistical significance; increasing laser speed resulted in decreased ductility and strain, smaller grain …
Performance Study Of Post-Processed Additively Manufactured Low Thrust Nozzles, Tyler W. Gerhold
Performance Study Of Post-Processed Additively Manufactured Low Thrust Nozzles, Tyler W. Gerhold
Theses and Dissertations
This research explores metal post-processing techniques to effectively reduce the large anomalous protrusions found in small additively manufactured low thrust rocket nozzles. Research has found that nozzles of this kind can experience losses in thrust of over 40%. Analytic theory of adiabatic nozzle flow with viscous losses for additively manufactured nozzles does not align with what has been found when tested experimentally. Compressible flow losses, such as shock wave formation inside the nozzle diverging cone, are likely the leading causes of such loss. Reduction in nozzle irregularities can likely yield results seen in analytic theory with similar performance to traditional …
Computational Based Investigation Of Lattice Cell Optimization Under Uniaxial Compression Load, Derek G. Spear, Jeremiah S. Lane, Anthony N. Palazotto, Ryan A. Kemnitz
Computational Based Investigation Of Lattice Cell Optimization Under Uniaxial Compression Load, Derek G. Spear, Jeremiah S. Lane, Anthony N. Palazotto, Ryan A. Kemnitz
Faculty Publications
Structural optimization is a methodology used to generate novel structures within a design space by finding a maximum or minimum point within a set of constraints. Topology optimization, as a subset of structural optimization, is often used as a means for light-weighting a structure while maintaining mechanical performance. This article presents the mathematical basis for topology optimization, focused primarily on the Bi-directional Evolutionary Structural Optimization (BESO) and Solid Isotropic Material with Penalization (SIMP) methodologies, then applying the SIMP methodology to a case study of additively manufactured lattice cells. Three lattice designs were used: the Diamond, I-WP, and Primitive cells. These …
Investigation Of Additively Manufactured Molybdenum-Tungsten-Rhenium Alloys, Randolph T. Abaya
Investigation Of Additively Manufactured Molybdenum-Tungsten-Rhenium Alloys, Randolph T. Abaya
Theses and Dissertations
The process of creating metal components through additive manufacturing is changing the way different industries can avoid the shortcomings of traditional metal production. Metals such as tungsten, molybdenum, and rhenium have many advantages for different applications, especially when alloyed together. In this study, an additively manufactured alloy containing 70% molybdenum, 25% tungsten, and 5% rhenium (70Mo-25W-5Re) is tested for its strength, ductility, hardness, and porosity. The 70Mo-25W-5Re alloy is printed through Laser Powder Bed Fusion (LPBF) under different conditions such as printing speed and printing atmosphere. Additionally, the effects of post printing heat treatment are conducted to understand the advantages …
Potential Solution To Meet Growing Demands Of Refractory Metal: Selective Laser Melting Of Molybdenum-Tungsten Alloy, Jae Yu
Theses and Dissertations
Selective laser melting (SLM) of refractory metals has been of high interest in research due to the metals’ potential desirable characteristics in aeronautical and space applications. In particular, molybdenum and tungsten have been the focus of several studies in the search for high temperature and high strength purposes in applications like supersonic aircraft, re-entry vehicles, nuclear fission, power generation, and other space systems. However, there is still a significant knowledge gap to process defect-free alloys and making use of them in practical engineering functions. The aim of this study is to characterize the relationship between the microstructure and mechanical properties …
Critical Evaluation Of Construction Industry-Related Additive Manufacturing Research: A Scientometric Analysis, Tyler J. Brunjes
Critical Evaluation Of Construction Industry-Related Additive Manufacturing Research: A Scientometric Analysis, Tyler J. Brunjes
Theses and Dissertations
Review of construction-related AM literature is used to identify the advantages, challenges, and current trends of the research. Using a scientometric analysis of 522 bibliographic records, this research systematically analyzed construction related AM research to determine the key research areas and trends. Results showed that starting in 2015, the field has been growing at an exponential rate. Recent AM research focused on materials and reinforcement topics, which matched the most notable challenges of AM, which are material rheology, reinforcement, and lacking construction standards. This study provides an insight into AM research and identifies areas requiring more innovation before its commercial …
Design And Testing Of A Composite Compressor Rotor, Mauro Noel V. De Leon
Design And Testing Of A Composite Compressor Rotor, Mauro Noel V. De Leon
Theses and Dissertations
Additive manufacturing (AM) and molding are manufacturing methods known for building representations or replicas of conceptualized engine components, but was considered impractical for manufacturing operating engine components. More recent technology has rendered composite materials (combining high-temperature polymers and fiber reinforcement) capable of withstanding the temperature and structural requirements to compete with conventional turbomachinery metals. This study explores the application of several high-temperature polymers (ULTEM 9085, Onyx-Carbon fiber, and Epoxy-Carbon fiber) and their survivability in the operating conditions of a P400 Engine compressor. The tests conducted for this study determined their viability as compressor materials. This study required conducting tensile specimen …
Effects Of A Nitrogen And Hydrogen Build Atmosphere On The Properties Of Additively Manufactured Tungsten, Dana C. Madsen
Effects Of A Nitrogen And Hydrogen Build Atmosphere On The Properties Of Additively Manufactured Tungsten, Dana C. Madsen
Theses and Dissertations
Additively manufactured tungsten was printed in pure nitrogen, nitrogen-2.5% hydrogen, and nitrogen-5% hydrogen atmospheres as part of a 2^3 full factorial designed experiment and subjected to room temperature and high-temperature three-point-bend testing, chemical analysis, hardness testing, and microstructural imaging techniques. The pure nitrogen specimens exhibited the highest strength and ductility at both high temperature and room temperature. Chemical analysis showed a 2-8x reduction in compositional oxygen relative to unprocessed powder. Hardness values for all samples was between 306.8 and 361.5 HV1. It is proposed that adding hydrogen into the build atmosphere reduced the available energy density for tungsten melting by …
Evaluation Of Additively Manufactured Lattices Under High Strain Rate Impact, Derek G. Spear
Evaluation Of Additively Manufactured Lattices Under High Strain Rate Impact, Derek G. Spear
Theses and Dissertations
Several additively manufactured lattice designs and configurations were evaluated under compression loads under various strain rates from quasi-static to highly dynamic. These experiments examined how the mechanical behavior of the lattice changed based on the lattice design properties and the applied strain rates. The modulus of elasticity, yield strength, plateau stress, and toughness were observed to decrease with an increase in strain rate, revealing that the lattice designs exhibit a negative strain rate sensitivity. A new lattice flow stress model was developed to account for the mechanical response of the lattice and was incorporated into a computational model for simulation. …
Investigation And Statistical Modeling Of The Mechanical Properties Of Additively Manufactured Lattices, Derek G. Spear, Anthony N. Palazotto
Investigation And Statistical Modeling Of The Mechanical Properties Of Additively Manufactured Lattices, Derek G. Spear, Anthony N. Palazotto
Faculty Publications
This paper describes the background, test methodology, and experimental results associated with the testing and analysis of quasi-static compression testing of additively manufactured open-cell lattice structures. The study aims to examine the effect of lattice topology, cell size, cell density, and surface thickness on the mechanical properties of lattice structures. Three lattice designs were chosen, the Diamond, I-WP, and Primitive Triply Periodic Minimal Surfaces (TPMSs). Uniaxial compression tests were conducted for every combination of the three lattice designs, three cell sizes, three cell densities, and three surface thicknesses. In order to perform an efficient experiment and gain the most information …
A Reduced Order Model Of The Celestial Icosahedron As The Substructure For A Lighter Than Air Vehicle, Torin C. Quick
A Reduced Order Model Of The Celestial Icosahedron As The Substructure For A Lighter Than Air Vehicle, Torin C. Quick
Theses and Dissertations
A finite element approach was used to investigate a novel reduced order model to determine the minimum structure dimensionality to support vacuum for a VLTAV. This modeling technique represented the individual segments of the substructure as curved beams with clamped radially-resisted boundary conditions. The full structure was then modeled as a bare structure and structure with skin to validate the results of the reduced order model. The beam geometry for the material Ultem 9085 was determined through this process leading to the 3-D printing of the structure. It was then experimentally tested under uniaxial compression complimented with a FEA model.
Improving Manufacturability And Reducing Cracking In Additively Manufactured Tungsten Alloys, Christopher P. Fassio
Improving Manufacturability And Reducing Cracking In Additively Manufactured Tungsten Alloys, Christopher P. Fassio
Theses and Dissertations
Additively Manufactured tungsten suffers from low () densities due to high concentrations of microcracks as the printed layers cool past tungsten's high ductile to brittle transition temperature. In this study, tungsten-rhenium and tungsten rhenium hafnium carbide compositions were evaluated on density and tensile strength. In addition to varying the compositions of each alloy, printing parameters and post-processing methods were also compared. Print parameters varied for all compositions on an MLab 200R C using included the laser scan strategy, hatch spacing, scan speed, laser power, and print bed material. Post processing techniques of the WRe compositions included hot isostatic pressing and …
Analysis For Hybrid Rocket Fuel Regression Using Stereolithographic Geometry, Michael P. King
Analysis For Hybrid Rocket Fuel Regression Using Stereolithographic Geometry, Michael P. King
Theses and Dissertations
Hybrid Rocket Engines (HRE) have characteristically low fuel regression that limits their performance. Additive manufacturing and rapid prototyping can possibly solve some of the problems with Hybrid propulsion regression by creating geometry not possible with conventional manufacturing. This work is attempting to make geometric regression simulation of HRE easier by using STereoLithography (STL files) as the geometry. This analysis sets flow conditions, boundary conditions, propellant selection, and allows for fuel geometry to be altered to simulate geometry’s effects on regression rate and propellant performance. This model can be used for more advanced geometric analysis to improve and predict performance.
3d Printing For Solving Part Obscolescence, Ayman G. Alqarni
3d Printing For Solving Part Obscolescence, Ayman G. Alqarni
Theses and Dissertations
The purpose of this research was to highlight the issue of parts obsolescence and to highlight the possibility of using alternative methods to overcome parts shortage. Specifically, this thesis sought to answer the research question: is the three-dimensional printing technology (3D) an applicable approach to overcome part obsolescence. The research question was answered through data research and survey analysis. Notwithstanding, the diminished manufacturing sources and material shortages (DMSMS) management and other existing approaches, such as forecasting, contracting, and reverse engineering (RE), were discussed briefly in the literature review and profoundly in chapter IV to differentiate among applicable existing solutions toward …
Investigation Of Ultem 9085 For Use In Printed Orbital Structures, William R. Gallagher
Investigation Of Ultem 9085 For Use In Printed Orbital Structures, William R. Gallagher
Theses and Dissertations
Additive manufacturing is revolutionizing industries ranging from medicine to space. However, the structural characteristics of plastic parts created by these methods are not as well understood as their more established counterparts. This research explored two relevant areas: how the structural characteristics of ULTEM 9085 plastic behaved after exposure to orbital conditions and the design of the cross-sectional area of a beam to be 3-D printed in microgravity based on the expected loads from the printer. To study orbital effects, ULTEM 9085 was printed into 1/4th scale ASTM D638- 14 dogbones using a Stratasys 450mc printer. These dogbones were placed in …
Structural Dynamic And Inherent Damping Characterization Of Additively Manufactured Airfoil Components, Andrew W. Goldin
Structural Dynamic And Inherent Damping Characterization Of Additively Manufactured Airfoil Components, Andrew W. Goldin
Theses and Dissertations
The push for low cost and higher performance/efficient turbine engines have introduced a new demand for novel technologies to improve robustness to vibrations resulting in High Cycle Fatigue (HCF). There have been many proposed solutions to this, some passive and some active. With the advent of Additive Manufacturing (AM), new damping techniques can now be incorporated directly into the design and manufacture process to suppress the vibrations that create HCF. In this study, this novel unfused pocket damping technology is applied to a blade structure and the resulting damping effectiveness is quantified. The application of this technology to complex geometries …
Solution Anneal Heat Treatments To Enhance Mechanical Performance Of Additively Manufactured Inconel 718, David J. Newell
Solution Anneal Heat Treatments To Enhance Mechanical Performance Of Additively Manufactured Inconel 718, David J. Newell
Theses and Dissertations
The nickel-based superalloy Inconel 718 (IN718) is an excellent candidate among aerospace alloys for laser powder-bed fusion (LPBF) manufacturing. As-built LPBF IN718 has a vertically aligned columnar (001) microstructure which translates into orthotropic mechanical behavior. The post-process heat treatments for IN718 were developed 60 years ago for wrought and cast processes and do not mitigate the columnar microstructure of the LPBF process. Recrystallization is required to remove the columnar microstructure, which would allow for parts to be fabricated on different machines or in different orientations but still achieve the same properties. This research investigated the microstructure of LPBF IN718 as …
Analysis Of Additively Manufactured Rings Under Compression Loading For Use In A Vacuum Lighter Than Air Vehicle Structure, Kevin D. Greenoe
Analysis Of Additively Manufactured Rings Under Compression Loading For Use In A Vacuum Lighter Than Air Vehicle Structure, Kevin D. Greenoe
Theses and Dissertations
A Vacuum Lighter Than Air Vehicle (VLTAV) utilizes a lightweight structure paired with an internal vacuum to achieve buoyancy; this allows it to float through-out a given atmosphere. The pressure differential between the internal vacuum andexternal atmosphere places the vehicle under intense loading. A specific structure under investigation is the celestial icosahedron, which features nine intersecting rings that have an outer diameter of 0.2032m and circular cross-sectionalthickness of 5.08mm.The celestials rings are positioned in three different orientations and are analyzed both experimentally and analytically.
Design, Development, And Testing Of A Low Cost, Additively-Manufactured, Centrifugal Compressor, Aaron P. Bauer
Design, Development, And Testing Of A Low Cost, Additively-Manufactured, Centrifugal Compressor, Aaron P. Bauer
Theses and Dissertations
The three objectives of this research were to: 1.) design, build, and test AM compressors to substitute into COTS micro-gas turbine engines, 2.) provide initial correlations between FEA and compressor failure speed, and 3.) characterize the effects of AM on compressor performance. These goals improved the design cycle cost and the design-validation time cycle. ULTEM 9085, 300-AMB, and Onyx-Kevlar temperature-dependent tensile properties were measured. FEA-predicted failure speeds of stock compressor designs led design improvements, potentially fulfilling the original compressor requirements. Physical testing of the stock and ULTEM 9085 compressors occurred. Comparing these compressors' performances demonstrated that low cost, AM materials …
An Analysis Of The Viability Of 3d-Printed Construction As An Alternative To Conventional Construction Methods In The Expeditionary Environment, Jeneé A. Jagoda
An Analysis Of The Viability Of 3d-Printed Construction As An Alternative To Conventional Construction Methods In The Expeditionary Environment, Jeneé A. Jagoda
Theses and Dissertations
Conventional construction is believed by some to have reached its technological limit of performance, making it increasingly difficult for conventional construction methods to meet the U.S. military’s core standards of quality, cost, and timeliness in the expeditionary environment. While still in its infancy, 3D-printed construction has the potential to revolutionize the way the military performs construction in deployed environments. This research conducts a systematic review of the viability of 3D-printed construction to investigate whether or not it is now or could be a viable replacement for conventional construction methods, specifically in remote environments where conventional construction capability may be limited. …
Effect Of Surface Roughness On Ultrasonic Inspection Of Electron Beam Melting Ti‐6al‐4v, Evan T. Hanks, Anthony N. Palazotto, David Liu
Effect Of Surface Roughness On Ultrasonic Inspection Of Electron Beam Melting Ti‐6al‐4v, Evan T. Hanks, Anthony N. Palazotto, David Liu
Faculty Publications
Experimental research was conducted on the effects of surface roughness on ultrasonic non-destructive testing of electron beam melted (EBM) additively manufactured Ti-6Al-4V. Additive manufacturing (AM) is a developing technology with many potential benefits, but certain challenges posed by its use require further research before AM parts are viable for widespread use in the aviation industry. Possible applications of this new technology include aircraft battle damage repair (ABDR), small batch manufacturing to fill supply gaps and replacement for obsolete parts. This paper aims to assess the effectiveness of ultrasonic inspection in detecting manufactured flaws in EBM-manufactured Ti-6Al-4V. Additively manufactured EBM products …
Analysis Of A Celestial Icosahedron Shaped Vacuum Lighter Than Air Vehicle, Dustin P. Graves, Kyle D. Moore, Anthony N. Palazotto
Analysis Of A Celestial Icosahedron Shaped Vacuum Lighter Than Air Vehicle, Dustin P. Graves, Kyle D. Moore, Anthony N. Palazotto
Faculty Publications
Excerpt: The celestial icosahedron geometry is considered as a potential design for a vacuum lighter than air vehicle. The goal of this research is ultimately to determine the feasibility of the design and to understand the initial fluid-structure interaction of the vacuum lighter than air vehicle and the surrounding airflow.
Application Of Metamaterials For Multifunctional Satellite Bus Enabled Via Additive Manufacturing, Michael A. Macchia
Application Of Metamaterials For Multifunctional Satellite Bus Enabled Via Additive Manufacturing, Michael A. Macchia
Theses and Dissertations
Space systems require materials with superior stiffness to weight ratios to provide structural integrity while minimizing mass. Additive manufacturing processes enable the design of metamaterials that exceed the performance of naturally occurring materials in addition to allowing the integration of non-structural functions. This research explored the use of a high stiffness, high density, small melt pool track width AM material, Inconel 718, to enable the production of metamaterials with finer features possible than can possibly be created using a lower density aluminum alloy material. Various metamaterials were designed utilizing thin wall triply periodic minimal surface infilled sandwich structures. The performance …
Thermal Management Of Satellite Electronics Via Gallium Phase Change Heat Sink Devices, Brian O. Palmer
Thermal Management Of Satellite Electronics Via Gallium Phase Change Heat Sink Devices, Brian O. Palmer
Theses and Dissertations
The purpose of this research was to determine the effectiveness and feasibility of additively manufactured heat sinks using gallium as a phase change material in the thermal management of satellite electronics. A design was created based on the footprint of an Astronautical Development, LLC Lithium 1 UHF radio and six heat sinks were additively manufactured; two each of stainless steel 316, Inconel 718, and ULTEM 9085. Each heat sink was filled with gallium for testing purposes. Models were created to simulate the behavior of the heat transfer and phase change processes occurring within the heat sink. Additionally, laboratory data was …