Open Access. Powered by Scholars. Published by Universities.®
Materials Science and Engineering Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Mechanical Engineering (84)
- Manufacturing (38)
- Metallurgy (26)
- Aerospace Engineering (24)
- Engineering Science and Materials (18)
-
- Electrical and Computer Engineering (15)
- Polymer and Organic Materials (14)
- Mechanics of Materials (13)
- Other Materials Science and Engineering (12)
- Structural Materials (10)
- Ceramic Materials (9)
- Physical Sciences and Mathematics (7)
- Structures and Materials (7)
- Biomedical Engineering and Bioengineering (6)
- Computer-Aided Engineering and Design (6)
- Operations Research, Systems Engineering and Industrial Engineering (6)
- Chemical Engineering (5)
- Chemistry (5)
- Industrial Engineering (5)
- Materials Chemistry (3)
- Medicine and Health Sciences (3)
- Nanoscience and Nanotechnology (3)
- Other Mechanical Engineering (3)
- Polymer Chemistry (3)
- Polymer Science (3)
- Applied Mechanics (2)
- Automotive Engineering (2)
- Civil and Environmental Engineering (2)
- Institution
-
- Missouri University of Science and Technology (30)
- Michigan Technological University (23)
- Air Force Institute of Technology (14)
- Boise State University (8)
- University of Louisville (8)
-
- Purdue University (7)
- University of Texas at El Paso (6)
- University of Nebraska - Lincoln (5)
- California Polytechnic State University, San Luis Obispo (4)
- New Jersey Institute of Technology (4)
- University of Kentucky (4)
- West Virginia University (4)
- Old Dominion University (3)
- Portland State University (3)
- Clemson University (2)
- Georgia Southern University (2)
- Harrisburg University of Science and Technology (2)
- LSU New Orleans (2)
- Louisiana State University (2)
- Louisiana Tech University (2)
- Montana Tech Library (2)
- The University of Akron (2)
- University of Arkansas, Fayetteville (2)
- University of Denver (2)
- University of New Mexico (2)
- Chapman University (1)
- Dartmouth College (1)
- Embry-Riddle Aeronautical University (1)
- Minnesota State University, Mankato (1)
- Mississippi State University (1)
- Publication Year
- Publication
-
- Materials Science and Engineering Faculty Research & Creative Works (16)
- Michigan Tech Publications, Part 1 (14)
- Electronic Theses and Dissertations (11)
- Theses and Dissertations (10)
- Department of Materials Science and Engineering Publications (6)
-
- Open Access Theses & Dissertations (6)
- Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research (5)
- Faculty Publications (5)
- Mechanical and Aerospace Engineering Faculty Research & Creative Works (5)
- Boise State University Theses and Dissertations (4)
- Doctoral Dissertations (4)
- Graduate Theses, Dissertations, and Problem Reports (ETD) (4)
- Materials Science and Engineering Faculty Publications and Presentations (4)
- 15th International Conference on Shot Peening (3)
- Dissertations (3)
- Masters Theses (3)
- Mechanical Engineering Faculty Publications (3)
- Michigan Tech Publications (3)
- All Dissertations (2)
- College of Graduate Studies: Theses & Dissertations (2)
- Graduate Theses & Non-Theses (2)
- Graduate Theses and Dissertations (2)
- Harrisburg University Other Works (2)
- LSU Doctoral Dissertations (2)
- LSU New Orleans Theses and Dissertations (2)
- Master's Theses (2)
- The Summer Undergraduate Research Fellowship (SURF) Symposium (2)
- Theses (2)
- Williams Honors College, Honors Research Projects (2)
- All Graduate Theses, Dissertations, and Other Capstone Projects (1)
- Publication Type
- File Type
Articles 31 - 60 of 156
Full-Text Articles in Materials Science and Engineering
Neural Operator And Physics-Informed Deep Learning Approaches For Inverse Design Of Composites And Manufacturing Processes, Minglei Lu
All Dissertations
In this dissertation, artificial intelligence (AI) models are designed and used to accelerate inverse design of composites and manufacturing processes. The critical bottlenecks in machine learning (ML) including data availability, data quality, model generalization and adaptation, interpretability, physical consistency, and the ’black box’ nature of models for the inverse design are addressed. And the proposed AI models are tested under different engineering scenarios. Firstly, a fast deep neural operator (DNO) structure was developed to significantly reduce training time. This model was tested in the context of additive manufacturing, a transformative industrial technology that allows for the creation of materials with …
Machine Learning-Driven Process Analysis And Optimization In Solid-State Welding And Fusion-Based Additive Manufacturing, Radif Uddin Ahmed
Machine Learning-Driven Process Analysis And Optimization In Solid-State Welding And Fusion-Based Additive Manufacturing, Radif Uddin Ahmed
Master's Theses
In the modern era of advanced manufacturing, optimizing process parameters is pivotal in ensuring the quality and reliability of sophisticated component fabrication. This study presents a novel, data-driven approach to parameter optimization in two cutting-edge manufacturing techniques: Friction Stir Welding (FSW) and Laser Powder Bed Fusion (LPBF). By leveraging machine learning methodologies, this research addresses the critical challenge of efficiently determining optimal process parameters, a task traditionally relying on time-consuming and resource-intensive trial-and-error methods. This study will lead to a robust data-driven framework for process analysis of more advanced manufacturing techniques like the Additive Friction Stir Deposition (AFSD) process. Friction …
Atmosphere Effects In Laser Powder Bed Fusion: A Review, Ben Brown, Cody Lough, Davis Wilson, Joseph Newkirk, Frank Liou
Atmosphere Effects In Laser Powder Bed Fusion: A Review, Ben Brown, Cody Lough, Davis Wilson, Joseph Newkirk, Frank Liou
Materials Science and Engineering Faculty Research & Creative Works
The use of components fabricated by laser powder bed fusion (LPBF) requires the development of processing parameters that can produce high-quality material. Manipulating the most commonly identified critical build parameters (e.g., laser power, laser scan speed, and layer thickness) on LPBF equipment can generate acceptable parts for established materials and moderately intricate part geometries. The need to fabricate increasingly complex parts from unique materials drives the limited research into LPBF process control using underutilized parameters, such as atmosphere composition and pressure. As presented in this review, manipulating atmosphere composition and pressure in laser beam welding has been shown to expand …
Synergistic Strategies In Hybrid Mxed Matrix 3d Printing Of Thermoplastics & Thermosets: Design, Manufacturing, And Materials Development., Saleh Akram Khanjar
Synergistic Strategies In Hybrid Mxed Matrix 3d Printing Of Thermoplastics & Thermosets: Design, Manufacturing, And Materials Development., Saleh Akram Khanjar
Electronic Theses and Dissertations
Composite manufacturing and mixed matrix structures have been produced using traditional manufacturing processes for various industrial applications due to their high mechanical properties to material weight and cost ratio. However implementation of composite and mixed matrix manufacturing with advanced manufacturing such as additive manufacturing is limited due to the hardware limitations of current 3d printing technologies and materials available for 3D printing applications. This work has developed and investigated a new hybrid 3D printing manufacturing process utilizing a variety of material systems (thermoplastic – thermoset, thermoplastic – thermoplastic, thermoset – thermoset, thermoplastic – thermoplastic – thermoset). This study developed thermoplastic …
Modeling Powder Spreadability In Powder-Based Processes Using The Discrete Element Method, Austin T. Sutton, M. Hossein Sehhat, Ming C. Leu, Joseph W. Newkirk
Modeling Powder Spreadability In Powder-Based Processes Using The Discrete Element Method, Austin T. Sutton, M. Hossein Sehhat, Ming C. Leu, Joseph W. Newkirk
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Powder-bed fusion (PBF) processes refer to a subset of Additive Manufacturing (AM) techniques where powder is spread on the build-plate before melting (by a laser or electron beam). While PBF processes are attractive due to their ability for realizing complex structures that are either difficult or impossible to create through conventional means, the parts fabricated with these techniques can exhibit defects such as pores, inclusions, and excessive surface roughness. To minimize these defects, much research has been dedicated towards process maturation by optimizing laser or electron beam parameters. However, these developmental efforts typically do not address the recoating process where …
Characterization Of Chopped Carbon Fiber Reinforced Composites Produced Using Fused Deposition Modeling, Jonathon Tran, Rachel Shubella
Characterization Of Chopped Carbon Fiber Reinforced Composites Produced Using Fused Deposition Modeling, Jonathon Tran, Rachel Shubella
Student Research Symposium
Fused deposition modeling (FDM) is an additive manufacturing (AM) process which can create parts with complex geometries in their final shape without need for additional specialized tools or devices. The FDM process builds parts by adding material layer by layer only where it is needed, saving energy, costs, production time for complex parts, and minimizing waste. Fiber reinforcement can significantly enhance the mechanical properties of a polymer material and depends significantly on the fiber length distribution and fiber orientation distribution of the final part. In this research, we investigated the various infill patterns of FDM printed Markforged onyx which is …
Process-Structure-Property-Performance Modeling For Semicrystalline Thermoplastics And Composites, Tatiana Stepanova
Process-Structure-Property-Performance Modeling For Semicrystalline Thermoplastics And Composites, Tatiana Stepanova
All Dissertations
With a growing focus on reducing the adverse effects of transportation on the environment, industries are seeking fuel-efficient and sustainable solutions. Fuel efficiency can be improved in several ways, but structural lightweighting has demonstrated overall effectiveness. In this regard, thermoplastic composites and additive manufacturing (AM) thermoplastics have become viable candidates for use in the automotive industry, given the need for weight reduction and efficiency improvement.
The advantages of AM include simplifying supply chains, simplifying part geometry, and enabling mass customization. In order to design high-performance AM structures, extensive modeling and simulation are required. AM thermoplastics are similar to conventional manufacturing …
Experimental Investigations And Optimization Of 3d Printed Cellular Structures For Protection Against Traumatic Brain Injury, Aaron R. Jackson
Experimental Investigations And Optimization Of 3d Printed Cellular Structures For Protection Against Traumatic Brain Injury, Aaron R. Jackson
Mechanical and Aerospace Engineering Dissertations - Archive
Traumatic Brain Injury (TBI) disrupts brain function due to head impacts, blast exposures, and ballistic penetrations. It is a significant cause of mental health issues and disability, particularly among military personnel. Historically, combat helmets were designed primarily to protect against fragments. However, recent data highlights the need for helmets that also protect against blast and blunt impacts. Effective TBI prevention requires helmets that address various energy threats while remaining lightweight. A critical metric in this effort is head acceleration, which is closely linked to injury across different scales of brain damage.
Four lattice structures were 3D printed using Digital ABS …
Sustainable Additive Manufacturing Of Polysulfone Membranes For Liquid Separations, Brian Leonard, Harrison Loh, David Lu, Ebuka A. Ogbuoji, Isabel Escobar, Konstantinos Sierros, Oishi Sanyal
Sustainable Additive Manufacturing Of Polysulfone Membranes For Liquid Separations, Brian Leonard, Harrison Loh, David Lu, Ebuka A. Ogbuoji, Isabel Escobar, Konstantinos Sierros, Oishi Sanyal
UK CARES Faculty Publications
Membranes serve as important components for modern manufacturing and purification processes but are conventionally associated with excessive solvent usage. Here, for the first time, a procedure for fabricating large area polysulfone membranes is demonstrated via the combination of direct ink writing (DIW) with non-solvent induced phase inversion (NIPS). The superior control and precision of this process allows for complete utilization of the polymer dope solution during membrane fabrication, thus enabling a significant reduction in material usage. Compared to doctor blade fabrication, a 63% reduction in dope solution volume was achieved using the DIW technique for fabricating similarly sized membranes. Cross …
Production Of Glass-To-Metal Seals Using Additive Manufacturing Techniques, Aaron Read
Production Of Glass-To-Metal Seals Using Additive Manufacturing Techniques, Aaron Read
Masters Theses
"Glass-to-metal (GtM) seals are hermetic barriers between glass and metal components, often used in the electronic and vacuum industries. Creating the seals traditionally requires heating all the components to the glass melting temperature, where the glass will flow and bond to the metal. Due to the manufacturing constraints of the individual components and sealing conditions there are geometric and material restrictions. Additive manufacturing techniques were used to make GtM seals to reduce these restrictions.
Hermetic, single pin seals were produced using printed metal shells, by selective laser melting (SLM), and digital light processing (DLP) printed glass preforms. Glass preforms were …
Additive Manufacturing Of Novel Lightweight Insulation Refractory With Hierarchical Pore Structures By Direct Ink Writing, Saisai Li, Jiaxuan Xin, Ruoyu Chen, Haiming Wen
Additive Manufacturing Of Novel Lightweight Insulation Refractory With Hierarchical Pore Structures By Direct Ink Writing, Saisai Li, Jiaxuan Xin, Ruoyu Chen, Haiming Wen
Materials Science and Engineering Faculty Research & Creative Works
A direct ink writing process using fly ash foaming slurries was employed for the additive manufacturing of lightweight mullite insulation refractory with hierarchical pore structures. The viscosity, thixotropy, and shear thinning behavior of the inks were analyzed to investigate the effect of the inorganic binder and dispersant of the foaming inks. A slurry exhibiting excellent rheological characteristics was identified, consisting of 45 wt% fly ash floating beads, 55 wt% water, 3.0 wt% additional dispersant, and 6.0 wt% additional binder. Furthermore, through the optimization of printing parameters such as printing pressure and printing speed, notable enhancements were achieved in the pore …
Development Of A Highly Loaded Zirconium Carbide Paste For Material Extrusion Additive Manufacturing, Clare Sabata, Austin J. Martin, Jeremy L. Watts, Gregory E. Hilmas
Development Of A Highly Loaded Zirconium Carbide Paste For Material Extrusion Additive Manufacturing, Clare Sabata, Austin J. Martin, Jeremy L. Watts, Gregory E. Hilmas
Materials Science and Engineering Faculty Research & Creative Works
A highly loaded, aqueous-based zirconium carbide (ZrC) paste was developed for ceramic on-demand extrusion (CODE). Commercial ZrC powder was ball milled to reduce the particle size to ∼1 μm. Paste composition was determined by rheological characterization and observation of printing behavior; the final paste consisted of 46–47 vol% ZrC, 43.5 vol% distilled water, 8.1 vol% dispersant, and 1.6 vol% binder. Rheological characterization of the paste showed a yield stress of ∼8 Pa and shear thinning behavior (ΔG′/Δσ* = −55). The paste was printed using a 610 μm nozzle; a test print showed shape fidelity using the developed paste. A pressureless …
Phenolic Polymer Infiltration And Pyrolysis Process For Additively Manufactured Carbon/Peek Composites To Produce Carbon–Carbon Composites, S. Weiler, H. A. Haffner, K. Chandrashekhara, J. Watts, G. E. Hilmas, J. Bayldon, L. M. Rueschhoff
Phenolic Polymer Infiltration And Pyrolysis Process For Additively Manufactured Carbon/Peek Composites To Produce Carbon–Carbon Composites, S. Weiler, H. A. Haffner, K. Chandrashekhara, J. Watts, G. E. Hilmas, J. Bayldon, L. M. Rueschhoff
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Carbon–carbon composites are carbon fibers reinforced with carbon matrix and are classified as advanced materials well suited for high-temperature structural applications. Carbon–carbon composites are characterized by maintaining excellent mechanical properties and structural stability at high temperatures and have been used in aerospace application as nozzles, heatshields, and leading edge. However, conventional methods to manufacture carbon–carbon composites are costly and time-consuming. the aim of this work is to develop a method for creating additively manufactured (AM) carbon–carbon composites using a high-pressure re-infiltration process. in doing so, less infiltration cycles are required compared to a low-pressure re-infiltration, reducing the total manufacture time. …
Advancements And Challenges In Additively Manufactured Functionally Graded Materials: A Comprehensive Review, Suhas Alkunte, Ismail Fidan, Vivekanand Naikwadi, Shamil Gudavasov, Mohammad Alshaikh Ali, Mushfig Mahmudov, Seymur Hasanov, Muralimohan Cheepu
Advancements And Challenges In Additively Manufactured Functionally Graded Materials: A Comprehensive Review, Suhas Alkunte, Ismail Fidan, Vivekanand Naikwadi, Shamil Gudavasov, Mohammad Alshaikh Ali, Mushfig Mahmudov, Seymur Hasanov, Muralimohan Cheepu
Engineering Technology Faculty Publications
This paper thoroughly examines the advancements and challenges in the field of additively manufactured Functionally Graded Materials (FGMs). It delves into conceptual approaches for FGM design, various manufacturing techniques, and the materials employed in their fabrication using additive manufacturing (AM) technologies. This paper explores the applications of FGMs in diverse fields, including structural engineering, automotive, biomedical engineering, soft robotics, electronics, 4D printing, and metamaterials. Critical issues and challenges associated with FGMs are meticulously analyzed, addressing concerns related to production and performance. Moreover, this paper forecasts future trends in FGM development, highlighting potential impacts on diverse industries. The concluding section summarizes …
Laser Deposition Additive Manufacturing Of Multi-Material And Metal-Ceramic Composite Structures, Manikanta Grandhi
Laser Deposition Additive Manufacturing Of Multi-Material And Metal-Ceramic Composite Structures, Manikanta Grandhi
Graduate Theses, Dissertations, and Problem Reports (ETD)
The increasing performance requirements of modern industrial systems, coupled with the imperative for decarbonization, necessitate a fundamental rethinking of metallic component design and manufacturing. Traditional materials, with their inherent limitations in property optimization, susceptibility to degradation, and weight constraints, are proving insufficient. Multi-material joining offers a potential solution, enabling designers to strategically integrate diverse materials with specific, tailored properties into single component. Functionally graded materials (FGMs) and oxide dispersion strengthened (ODS) materials are prime examples of this approach, delivering substantial improvements in wear resistance, thermal regulation, high-temperature resilience, and overall weight efficiency. However, conventional manufacturing approaches further exacerbate the limitations …
Investigating The Role Of Tesserae In Energy Absorption In Shark Cartilage, Molly Dobrow
Investigating The Role Of Tesserae In Energy Absorption In Shark Cartilage, Molly Dobrow
UNF Graduate Theses and Dissertations
Unlike mammals, shark endoskeletons are composed of cartilage, which is less stiff compared to bone. Despite this structural disadvantage, sharks have risen to become apex predators, with reported maximum posterior bite force estimates approximating 5914 N in bull sharks. Shark jaws are estimated to undergo high cycle loading within the organism’s lifecycle without evidence of failure. Fatigue resistance may relate to mineral distribution within a component of the endoskeletal system – tesserae. Tesserae are thin, roughly hexagonal tiles composed of calcium phosphate hydroxyapatite (HA) crystals and grow by accretion to eventually surround the hyaline cartilage core. Though tesserae dimensions are …
Advancing Additive Manufacturing For Biomedical Applications: Antimicrobial And X-Ray Absorptive Composite Filaments For Fused Filament Fabrication, John M. Arnold Jr
Advancing Additive Manufacturing For Biomedical Applications: Antimicrobial And X-Ray Absorptive Composite Filaments For Fused Filament Fabrication, John M. Arnold Jr
LSU New Orleans Theses and Dissertations
The objective of this research was to investigate the use of nano- and microparticle amendments for the creation of Poly-lactic Acid composite materials for use in biomedical applications using the Fused Filament Fabrication process of Additive Manufacturing. Composites were created with the goal of imparting the useful properties of antimicrobial activity and x-ray absorption to the material. In addition to testing the efficacy of the particle amendments in achieving the desired properties, the thermal and mechanical properties of the composite materials were tested to ensure that the composites would be compatible with the Fused Filament Fabrication process and would produce …
Additive Manufacturing Of Microelectronic Devices For Extreme Environments, Nicholas Mckibben
Additive Manufacturing Of Microelectronic Devices For Extreme Environments, Nicholas Mckibben
Boise State University Theses and Dissertations
This work encompasses a comprehensive exploration of advanced manufacturing techniques for fabricating microelectronic devices compatible with extreme environments. The research integrates the fields of chemistry, nanomaterials, and additive manufacturing to achieve remarkable progress in sensor development, with a particular emphasis on aerosol jet printing (AJP), surface acoustic wave (SAW) devices, patterned graphene growth, and surface functionalization. The investigation begins with the AJP process development of a commercial silver nanoparticle ink, culminating in the fabrication of a piezoelectric SAW transducer that was prototyped as a high-temperature thermometer, showing excellent linearity when validated to 200°C. Next, the investigation continued with the development …
Characterization Of Interlayer Laser Shock Peening During Fused Filament Fabrication Of Polylactic Acid (Pla), Fabien Denise
Characterization Of Interlayer Laser Shock Peening During Fused Filament Fabrication Of Polylactic Acid (Pla), Fabien Denise
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
The field of additive manufacturing (AM) has gained a significant amount of popularity due to the increasing need for more sustainable manufacturing techniques and the adaptive development of complex product geometries. The problem is that AM parts routinely exhibit flaws or weaknesses that affect functionality or performance. Over the years, surface treatments have been developed to compensate certain flaws or weaknesses in manufactured products. Combining surface treatments with the modularity of additive manufacturing could lead to more adaptable and creative improvements of product functions in the future. The current work evaluates the feasibility of pursuing a new research axis in …
Investigation Of Deformation Behavior Of Additively Manufactured Aisi 316l Stainless Steel With In Situ Micro-Compression Testing, Fei Teng, Ching-Heng Shiau, Cheng Sun, Robert C. O'Brien, Michael D. Mcmurtrey
Investigation Of Deformation Behavior Of Additively Manufactured Aisi 316l Stainless Steel With In Situ Micro-Compression Testing, Fei Teng, Ching-Heng Shiau, Cheng Sun, Robert C. O'Brien, Michael D. Mcmurtrey
Materials Science and Engineering Faculty Publications and Presentations
Additive manufacturing techniques are being used more and more to perform the precise fabrication of engineering components with complex geometries. The heterogeneity of additively manufactured microstructures deteriorates the mechanical integrity of products. In this paper, we printed AISI 316L stainless steel using the additive manufacturing technique of laser metal deposition. Both single-phase and dual-phase substructures were formed in the grain interiors. Electron backscatter diffraction and energy-dispersive X-ray spectroscopy indicate that Si, Mo, S, Cr were enriched, while Fe was depleted along the substructure boundaries. In situ micro-compression testing was performed at room temperature along the [001] orientation. The dual-phase substructures …
Fatigue And Fracture Of Electron Beam Melting Ti-6al-4v, William A. Grell
Fatigue And Fracture Of Electron Beam Melting Ti-6al-4v, William A. Grell
Electronic Theses and Dissertations
For applications in the aerospace field, selection of materials for a given design requires an understanding of critical properties, like fatigue and fracture, in addition to static mechanical and physical properties. With the ongoing advancements in metallic additive manufacturing techniques and the interest in applying the process to aerospace applications, there is a clear need to fully characterize properties. Arguably, the most attractive alloy for applications in aerospace is the Ti-6Al-4V alloy. The current dissertation examines the mechanical properties of the alloy, made by the Electron Beam Melting (EBM) Powder Bed Fusion (PBF) method. As illustrated in this work, the …
Point Heat Source Correlation To Microstructural Evolution In Advanced Manufacturing, Mark Anderson
Point Heat Source Correlation To Microstructural Evolution In Advanced Manufacturing, Mark Anderson
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Although there are different ways that advanced manufacturing can be performed, the use of single-point heat sources has become the standard to control a final product’s properties. It is imperative to understand how the heat source used in the different advanced manufacturing processes affect the microstructure of interest. The intimate relationship between the heat source and microstructure allows for controlling and tailoring a part’s properties. Utilizing different microstructural analysis, the cross-correlation of various point heat sources to developed microstructure was conducted in this dissertation.
Laser powder bed fusion allows for unique print-to-part protocols, but the dynamics of the process makes …
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 …
Development Of Novel Turbomachinery Manufacturing Methods, Timothy P. Winkler
Development Of Novel Turbomachinery Manufacturing Methods, Timothy P. Winkler
Theses and Dissertations
Compact turbine engines are of increasing interest as a means of propulsion for small, lightweight, low cost, unmanned aerial systems. This study looks to leverage advancements in novel manufacturing technology to produce turbomachinery components while simultaneously reducing costs and manufacturing time. To determine the feasibility of drop-in replacements for stock components this study focused on several research areas. This included materials research on both polymer-reinforced and ceramic materials, specimen tensile testing to determine temperature-dependent material properties, finite element analysis of multiple candidate materials, design and fabrication of a spin test rig, and physical spin testing of manufactured components to predict …
Material Property Dependence Of Nanoparticle Silicon Carbide Alloying In Additively Manufactured Molybdenum, Andrew P. Mason
Material Property Dependence Of Nanoparticle Silicon Carbide Alloying In Additively Manufactured Molybdenum, Andrew P. Mason
Theses and Dissertations
The structural performance of additively manufactured Mo printed by LPBF can be significantly improved by nanoparticle alloying. Previous AFIT studies of SiC nanoparticle addition conducted by Ellsworth (2022) et al. demonstrated increased powder consolidation, leading to reduced porosity, increased microhardness, and a shift in atomic defect concentrations. The addition of defected SiC particles is proposed to reduce in situ oxidation by acting as a sacrificial oxidizing agent and contributing to the formation of Mo disilicide secondary phases. This study investigated the relationship between laser powder bed fusion Mo microscale and nanoscale properties with varying SiC particle size while maintaining a …
Influence Of Dilute Silicon Carbide Nanoparticle Additions To The Microstructure And Mechanical Properties Of Laser Powder Bed Fusion Molybdenum, Nathan E. Ellsworth
Influence Of Dilute Silicon Carbide Nanoparticle Additions To The Microstructure And Mechanical Properties Of Laser Powder Bed Fusion Molybdenum, Nathan E. Ellsworth
Theses and Dissertations
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 temperatures. Nano-sized silicon carbide particles (0.1 wt%) were homogeneously mixed with molybdenum powder and the printing characteristics, chemical composition, microstructure, and mechanical properties were compared to pure molybdenum for scan speeds of 100, 200, 400, and 800 mm/s. The addition of silicon carbide improved the consolidation and mechanical properties and the oxygen content was reduced. Two mechanisms of oxygen reduction were identified as responsible for the improvements: oxidation of free carbon and the creation …
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 …
Performance Evaluation Of Composite Sandwich Structures With Additively Manufactured Aluminum Honeycomb Cores With Increased Bonding Surface Area, M. Rangapuram, S. K. Dasari, Joseph William Newkirk, K. Chandrashekhara, H. Misak, P. R. Toivonen, D. Klenosky, T. Unruh, J. Sam
Performance Evaluation Of Composite Sandwich Structures With Additively Manufactured Aluminum Honeycomb Cores With Increased Bonding Surface Area, M. Rangapuram, S. K. Dasari, Joseph William Newkirk, K. Chandrashekhara, H. Misak, P. R. Toivonen, D. Klenosky, T. Unruh, J. Sam
Materials Science and Engineering Faculty Research & Creative Works
Modern aerostructures, including wings and fuselages, increasingly feature sandwich structures due to their high-energy absorption, low weight, and high flexural stiffness. The face sheet of these sandwich structures are typically thin composite laminates with interior honeycombs made of Nomex or aluminum. Standard cores are structurally efficient, but their design cannot be varied throughout the structure. With additive manufacturing (AM) technology, these core geometries can be altered to meet the design requirements that are not met in standard honeycomb cores. This study used a modified aluminum honeycomb core, with increased surface area on the top and bottom, as the core material …
Additive Manufacturing Of (Mgconicuzn)O High-Entropy Oxide Using A 3d Extrusion Technique And Oxide Precursors, Ruoyu Chen, Saisai Li, Qingfeng Yan, Haiming Wen
Additive Manufacturing Of (Mgconicuzn)O High-Entropy Oxide Using A 3d Extrusion Technique And Oxide Precursors, Ruoyu Chen, Saisai Li, Qingfeng Yan, Haiming Wen
Materials Science and Engineering Faculty Research & Creative Works
This report presents an additive manufacturing approach, for the first time, to producing high-entropy oxides (HEOs) using a 3D extrusion-based technique with oxide precursors. The precursors were prepared by a wet chemical method from sulfates. Additives were utilized to optimize the rheological properties of the printing inks with these precursors, and the properties of the printed HEOs were improved by increasing the solid content of the inks. When ink with a solid content of 78 wt% was used for printing, the resulting HEO exhibited a relative density of 92% and a high dielectric constant after undergoing pressure less sintering at …
Multimaterial, Core-Shell Direct Ink Writing Of Flexible Strain Sensors For Pneumatically-Actuated Soft Robotic Hinge Joints, John Michael Burke
Multimaterial, Core-Shell Direct Ink Writing Of Flexible Strain Sensors For Pneumatically-Actuated Soft Robotic Hinge Joints, John Michael Burke
Graduate Theses, Dissertations, and Problem Reports (ETD)
Direct ink writing (DIW) provides for an expansive material library and the ability to print multiple materials with tailored functionalities in a controllable and single-step process. Particularly beneficial is the net shape printing under ambient conditions of a wide range of materials normally incompatible with one another. Coaxial DIW is a 3D printing technique that allows for two dissimilar inks to be extruded simultaneously in a co-flow manner. In this work, custom-designed coaxial nozzles were 3D-printed using a stereolithography printer. Composite inks comprised of thermoplastic polyurethane and silver were developed and studied. The coaxial nozzles were then used to co-extrude …