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Ljm Rc Baja Vehicle Project Chassis And Suspension, Paul Lervick Jan 2022

Ljm Rc Baja Vehicle Project Chassis And Suspension, Paul Lervick

All Undergraduate Projects

An RC car was designed, analyzed, and manufactured to compete in the ASME RC Baja competition. The focus was to optimize the suspension and chassis components to minimize the weight while maintaining the structural strength of the components which would intern supplement the overall speed and stability of the vehicle. Other components were the responsibility of the teammate Cam Jamison. To complete this there was extensive research done on Traxxas RC cars and what went into making a high-performing vehicle that would compete well in the 3 races that comprise the competition (slalom, sprint, and obstacle course). There were then …


Development Of Oxide Dispersion Strengthening (Ods) Alloys Powder For Additive Manufacturing, Changyu Ma Jan 2022

Development Of Oxide Dispersion Strengthening (Ods) Alloys Powder For Additive Manufacturing, Changyu Ma

Graduate Theses, Dissertations, and Problem Reports

Additive manufacturing (AM) fabricated oxide dispersion strengthened (ODS) alloys are given high expectations for critical structural components such as the first stage turbine blade for their excellent creep strength and oxidation resistance compared to superalloys. However, the powder feedstock processing is still an open question since current state-of-the-art processes are not capable of achieving ultrafine strengthening elements such as Y2O3 in powder which leads to agglomeration issues in as-consolidated alloys. In this research, the oxidation behavior and stability of ultrafine oxide in AM-printed alloys using mechanically alloyed powders were evaluated at 1100 oC. In addition, a …


Vibration Bending Fatigue Analysis Of Additively Repaired Ti-6al-4v Airfoil Blades, Lucas Jordan Smith Jan 2022

Vibration Bending Fatigue Analysis Of Additively Repaired Ti-6al-4v Airfoil Blades, Lucas Jordan Smith

Browse all Theses and Dissertations

Repairing airfoil blades is necessary to extend the life of turbine engines. Directed energy deposition (DED) additive manufacturing (AM) provides the ability to add material at a specific location on an existing component. In this work, AM repairs on Ti-6Al-4V airfoil blades were analyzed to determine what effect the repair will have on the blade performance in high cycle vibration fatigue testing. Targeted sections were cut out of airfoil blades near high stress locations and repaired using DED. To understand the defects that arose with this type of repair, computed tomography imaging was used to quantify the defects from the …


A Study Of Reduced Activation Ferritic Martensitic Metal Core Wire For Wire Arc Additive Manufacturing, Alexander L. Reichenbach Jan 2022

A Study Of Reduced Activation Ferritic Martensitic Metal Core Wire For Wire Arc Additive Manufacturing, Alexander L. Reichenbach

Electronic Theses and Dissertations

This study seeks to determine the technical feasibility of fabricating reduced activation ferritic martensitic (RAFM) steel parts, using a wire arc additive manufacturing (WAAM) process. The WAAM process, manufactures a part by depositing layers of metal onto a substrate to build a large scale near net shape part. RAFM alloy steels are next generation steels designed to resist radiation effects in the radiation intense working environments, such as nuclear reactors. To achieve this, process development and testing to design the WAAM production process with the custom RAFM filler wire was carried out. Several welding waveform modes were tested, and it …


Electron Beam Melted Parameter Development Of Pure Tungsten & Post-Processing Hip And Heat Treatment Of Gamma Titanium Aluminide, Kurtis Isami Watanabe Dec 2021

Electron Beam Melted Parameter Development Of Pure Tungsten & Post-Processing Hip And Heat Treatment Of Gamma Titanium Aluminide, Kurtis Isami Watanabe

Open Access Theses & Dissertations

Pure tungsten is a refractory metal and has been gaining interest for the use in nuclear fusion reactors as a plasma facing material. Titanium Aluminide (TiAl) has been growing in popularity as a possibly to phase out Nickel based superalloys due to its high specific strength at elevated temperatures. These two materials suffer from poor machinability due to being brittle at room temperature. Additive manufacturing (AM) is a recently developed manufacturing method that is fundamentally different than formative or subtractive. AM is a layer-by-layer process that has the potential to manufacture metals to a near net shape. Since the AM …


Nonmetallic Jet Impingement Thermal Management For Power Electronics Via Additive Manufacturing, Reece Whitt Dec 2021

Nonmetallic Jet Impingement Thermal Management For Power Electronics Via Additive Manufacturing, Reece Whitt

Graduate Theses and Dissertations

The increase in energy demanded by transportation and energy sectors has necessitated highly efficient thermal management for reliable power electronics operations. Conventional cooling techniques are limited by their inability to target switching location hot spot temperatures, leading to non-uniform thermal gradients. These devices, such as cold plates and heat sinks, also utilize heavy metallic structures that can accentuate electromagnetic interferences generated by high voltage switching processes. This work proposes a non-metallic jet impingement cooler for more customized thermal management, while simultaneously reducing the harmful effects of electromagnetic interferences. Additive manufacturing is utilized to enable jet impingement zones to target individual …


Design And Fabrication Of A Polymer Fdm Printer Capable Of Build Parameter Monitoring And In-Sit Geometric Monitoring Via Photogrammetry, Travis Roberts Dec 2021

Design And Fabrication Of A Polymer Fdm Printer Capable Of Build Parameter Monitoring And In-Sit Geometric Monitoring Via Photogrammetry, Travis Roberts

All Theses

Additive manufacturing, or 3D printing, is a complex process that creates free-form geometric objects by sequentially placing material in a location to construct an object, usually as a layer-by-layer process. One of the most widespread methods is Fused Deposition Modeling (FDM). FDM is used in many of the consumer-grade polymer 3D printers available today. While consumer grade machines are cheap and plentiful, they lack many of the features desired in a machine used for research purposes and are often closed-source platforms. Commercial-grade models are more expensive and are also usually closed-source platforms that do not offer flexibility for modifications often …


Additive Manufacturing Of Cork, A Cold Spray Technology, Kimberly Kay Dickey Dec 2021

Additive Manufacturing Of Cork, A Cold Spray Technology, Kimberly Kay Dickey

Theses and Dissertations

Cold Spray Additive Manufacturing is a technology capable of mass manufacturing components with complicated geometry and coating substrates in hard-to-reach areas. In addition, cold spray also has the ability of conducting a green manufacturing process, with zero waste of renewable feed material, and zero gas and chemical emission. This paper investigates solely cold spray as an additive manufacturing technology with cork as the natural material. CFD results were used to predict the physical behavior of air and the cork particles. After unsuccessful coatings, final results showed that when moisture is added, cork is successfully cold sprayed, and agglomeration is experienced. …


Assessing Mechanical Performance Of Dissimilar Steel Systems Made Via Wire-Arc Additive Manufacturing, Obed Daniel Acevedo Dec 2021

Assessing Mechanical Performance Of Dissimilar Steel Systems Made Via Wire-Arc Additive Manufacturing, Obed Daniel Acevedo

Masters Theses

Hot stamping is part of a specific type of metalworking procedure widely used in the automotive industry. This research seeks to help make hot stamp tooling component production more cost-effective by using large-scale additive manufacturing. Additive manufacturing can produce dissimilar steel components that can be more cost-effective and time-efficient and allow for complex geometries to be made. A dissimilar steel system consisting of 410 martensitic stainless steel and AWS ER70S-6 mild steel is proposed to make hot stamps, making them more cost-efficient. However, the material interface's mechanical behavior in 410SS-mild steel additively manufactured material systems is not well understood. This …


Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen Aug 2021

Laser Surface Treatment And Laser Powder Bed Fusion Additive Manufacturing Study Using Custom Designed 3d Printer And The Application Of Machine Learning In Materials Science, Hao Wen

LSU Doctoral Dissertations

Selective Laser Melting (SLM) is a laser powder bed fusion (L-PBF) based additive manufacturing (AM) method, which uses a laser beam to melt the selected areas of the metal powder bed. A customized SLM 3D printer that can handle a small quantity of metal powders was built in the lab to achieve versatile research purposes. The hardware design, electrical diagrams, and software functions are introduced in Chapter 2. Several laser surface engineering and SLM experiments were conducted using this customized machine which showed the functionality of the machine and some prospective fields that this machine can be utilized. Chapter 3 …


Transients In Plastic Instabilities During Thermo-Mechanical Reversals In An Additively Manufactured Ti6al4v, Sabina C. Kumar Aug 2021

Transients In Plastic Instabilities During Thermo-Mechanical Reversals In An Additively Manufactured Ti6al4v, Sabina C. Kumar

Doctoral Dissertations

A complex interaction of process variables in an evolving geometry during Additive Manufacturing (AM), can bring about spatial and temporal transients of temperature and stress within each layer in a part. Although AM shares commonalities with conventional processing techniques such as casting, welding, and thermo-mechanical process, published literature has shown that the steady-state conditions are not strictly valid during AM process. Macro-scale fluctuations of thermal gradients (dT/dx: 103 to 107 K/m) combined with local changes in thermal expansion coefficients, crystallographic strains and localized stress-strain constitutive properties in conjunction with thermal cycles, can bring about a plastic strain gradient …


Development Of A Laser Solder Process For Use With Material Extrusion Additive Manufacturing And Rapid Electronics Prototyping In Embedded Sensing Applications, Emerson Roland Armendariz Aug 2021

Development Of A Laser Solder Process For Use With Material Extrusion Additive Manufacturing And Rapid Electronics Prototyping In Embedded Sensing Applications, Emerson Roland Armendariz

Open Access Theses & Dissertations

Industrial and rapid prototyping (RP) trends toward miniaturization of electronic devices containing temperature sensitive electronics and surrounding materials are calling for highly controllable, selective laser soldering technologies. Laser soldering is a non-contact technique that eliminates the risk of marring or damaging sensitive components by precisely focusing a laser beam on a solder filler alloy, leading to a fast and non-destructive electrical joint. Using the benefits of accurate and controlled heat delivery via inexpensive low power laser diodes (LPDL's) in conjunction with ever-increasing additive manufacturing capability in producing complex internal features and geometries, development and testing of a laser application system …


Development Of A Wireless Telemetry Load And Displacement Sensor For Orthopaedic Applications, William Anderson Jul 2021

Development Of A Wireless Telemetry Load And Displacement Sensor For Orthopaedic Applications, William Anderson

Electronic Thesis and Dissertation Repository

Due to sensor size and supporting circuitry, in vivo load and deformation measurements are currently restricted to applications within larger orthopaedic implants. The objective of this thesis is to repurpose a commercially available low-power, miniature, wireless, telemetric, tire-pressure sensor (FXTH87) to measure load and deformation for future use in biomechanical applications. The capacitive transducer membrane of the FXTH87 was modified, and a relationship was reported between applied compressive deformation and sensor signal value. The sensor package was embedded within a deformable enclosure to illustrate potential applications of the sensor for monitoring load. Finite element analysis was an effective tool to …


Computational Frameworks For Multi-Robot Cooperative 3d Printing And Planning, Laxmi Prasad Poudel Jul 2021

Computational Frameworks For Multi-Robot Cooperative 3d Printing And Planning, Laxmi Prasad Poudel

Graduate Theses and Dissertations

This dissertation proposes a novel cooperative 3D printing (C3DP) approach for multi-robot additive manufacturing (AM) and presents scheduling and planning strategies that enable multi-robot cooperation in the manufacturing environment. C3DP is the first step towards achieving the overarching goal of swarm manufacturing (SM). SM is a paradigm for distributed manufacturing that envisions networks of micro-factories, each of which employs thousands of mobile robots that can manufacture different products on demand. SM breaks down the complicated supply chain used to deliver a product from a large production facility from one part of the world to another. Instead, it establishes a network …


A Framework To Aid Decision Making For Smart Manufacturing Technologies In Small-And Medium-Sized Enterprises, Purvee Bhatia Jun 2021

A Framework To Aid Decision Making For Smart Manufacturing Technologies In Small-And Medium-Sized Enterprises, Purvee Bhatia

USF Tampa Graduate Theses and Dissertations

The fourth industrial revolution or Industry 4.0 has changed today’s manufacturing scenario. The transition to smart manufacturing technologies has been evolving over the last few years and has recently accelerated due to the pandemic. The need to make manufacturing systems agile, adaptive, resilient, and robust has expediated the adoption and implementation of smart manufacturing technologies.

Despite the interest of manufacturers in smart manufacturing, the adoption rate has been slow due to the lack of decision-making tools that can provide a clear strategic roadmap for effective execution. Small and medium sized enterprises (SMEs) are especially slow in adoption due to the …


Med-Drop Pill Dispenser, Cole Pike, Taylor Morris, Christopher Bruni, Jose Gomez Jun 2021

Med-Drop Pill Dispenser, Cole Pike, Taylor Morris, Christopher Bruni, Jose Gomez

Mechanical Engineering

Veterans’ Affairs home care nurses currently spend anywhere from thirty minutes to two hours filling out monthly prescriptions one pill at a time to veterans who are unable to leave their homes. The goal of this project was to create an easy-to-use device that could be left at a patient’s home that nurses could use to quickly and accurately dispense medication into the patient’s monthly pill box.


Multiscale And Multimaterial 3d Printing: Impact Of Feedstock Properties And Processing Parameters On Printed Parts, Kazi Md Masum Billah May 2021

Multiscale And Multimaterial 3d Printing: Impact Of Feedstock Properties And Processing Parameters On Printed Parts, Kazi Md Masum Billah

Open Access Theses & Dissertations

Material extrusion additive manufacturing (AM) technology is one of the most commonly used technology to fabricate functional prototypes and end-use application parts with custom design. The evolution of the extrusion technology led this particular AM process to grow in many aspects such as new materials development, new design thinking, fabrication of parts in multiscale length, and manufacturing of monolithic parts with multiple functionalities. The research presented in this Dissertation results in the creation of knowledge in material extrusion AM technology with the length scale of production-grade to large-scale 3D printing machine those were used to enable the fabrication of multimaterial …


Design Of A Cable-Driven Manipulator For Large-Scale Additive Manufacturing, Phillip Chesser May 2021

Design Of A Cable-Driven Manipulator For Large-Scale Additive Manufacturing, Phillip Chesser

Masters Theses

Additive manufacturing of concrete is a growing field of research, yet current motion platforms do not offer viable routes towards large scale deployable systems. This thesis presents the design and analysis of a novel cable-driven robot for use in large scale additive manufacturing. The system developed, termed SkyBAAM, is designed to be easily deployable to a construction site for on-site additive manufacturing of buildings and other large structures. The design philosophy behind this system is presented. Analysis of this system first explores the kinematics, and stiffness as a function of cable tension. Analysis of the workspace and singularities is also …


Prediction Of Residual Stress And Distortion In Laser Powder Bed Fusion Additive Manufacturing, Bhanuprakash Sairam Kosaraju Apr 2021

Prediction Of Residual Stress And Distortion In Laser Powder Bed Fusion Additive Manufacturing, Bhanuprakash Sairam Kosaraju

Theses and Dissertations

Additive Manufacturing (AM) has its proven advantages to unlock the design space and manufacturing capabilities for complex geometries with lightweights. Distortion is one of the most common defects that occur in Laser Powder Bed Fusion Additive Manufacturing (LPBFAM), which is caused by the significant residual stress during the printing process. This can lead to numerous process iterations to achieve the requisite form and fit tolerances.

In this study, Finite Element (FE) model that utilizes the element birth approach was developed to predict the residual stress and distortion in the LPBFAM process. The methodology leverages a simplified approach where the detailed …


Corrosion Performance Of Additively Manufactured Alloys And Hot Corrosion, Ali Hemmasian Ettefagh Jan 2021

Corrosion Performance Of Additively Manufactured Alloys And Hot Corrosion, Ali Hemmasian Ettefagh

LSU Doctoral Dissertations

Additive manufacturing (AM) has gained attention in recent years due to its unique properties in the fabrication of complex parts. Same as any other new topics, in some areas, there is still a lack of enough knowledge and there is the need for further investigations to enable the applications of AM parts widely in industries. ‎Chapter 2, and ‎Chapter 5 to ‎Chapter 8 of this report are focused on the corrosion properties of the parts and coatings fabricated using the laser powder bed fusion based AM method or laser surface processing method, including a comprehensive review. Laser powder bed fusion …


Development Of In-Situ Radiometric Inspection Methods For Quality Assurance In Laser Powder Bed Fusion, Cody S. Lough Jan 2021

Development Of In-Situ Radiometric Inspection Methods For Quality Assurance In Laser Powder Bed Fusion, Cody S. Lough

Doctoral Dissertations

“Laser Powder Bed Fusion (LPBF) metal Additive Manufacturing (AM) fabricates 3D metal parts layer-by-layer. The process enables production of geometrically complex parts that are difficult to inspect with traditional methods. The LPBF parts experience significant geometry driven thermal variations during manufacturing. This creates microstructure and mechanical property inhomogeneities and can stochastically cause defects. Mission critical applications require part qualification by measuring the defects non-destructively. The layer-to-layer nature of LPBF permits non-intrusive measurement of radiometric signals for a part’s entire volume. These measurements provide thermal features that correlate with the local part health. This research establishes Optical Emission Spectroscopy (OES) and …


Sources Of Quality Uncertainty In Laser Powder Bed Fusion Metal Additive Manufacturing, Zachary Young Jan 2021

Sources Of Quality Uncertainty In Laser Powder Bed Fusion Metal Additive Manufacturing, Zachary Young

Doctoral Dissertations

"Powder based additive manufacturing (AM) exhibits tremendous uncertainties, where variations in build quality is present despite utilizing similar build processing parameters. First, this work reports the features and formation mechanisms of five unique types of spatter during the LPBF process by in-situ high-speed, high-energy x-ray imaging. The unique physical characteristics of spatter are determined. The effect of laser scan speed and laser power on spatter formation, ejection, and mitigation are determined. Second, this work addresses the uncertainty challenge by identifying the sources of uncertainty in SLM by in-situ characterization due to variations from the additive manufacturing processing parameters needed for …


Design For Additive Manufacturing (3d Printing), Michael O'Donnell, Michael J. Levy Jan 2021

Design For Additive Manufacturing (3d Printing), Michael O'Donnell, Michael J. Levy

Williams Honors College, Honors Research Projects

The goal of this project is to study the performance of a 3D printed mechanical part subjected to topology optimization. A part that is somewhat complex in its load bearing and geometry will be selected. That part will then be designed, finite element analysis will be performed on it to optimize its topology, and then it will be 3D printed and tested. The goal of topology optimization is to either save material cost and/or part weight due to the ability of 3D printing to manufacture parts with complex and obscure geometry.


Feasibility Of Additive Manufacturing For Vibration Isolation Systems, Matthew Youngblood, Christian Velo, Gary Facemyer Jan 2021

Feasibility Of Additive Manufacturing For Vibration Isolation Systems, Matthew Youngblood, Christian Velo, Gary Facemyer

Williams Honors College, Honors Research Projects

During transport sensitive payloads can become subject to a multitude of vibration or shock environments that can lead to damage. Using only additive manufacturing we seek to design an isolation system that can provide enough vibration and shock damping to properly protect the payload. Using modern FEA software we were able to quickly analyze a variety of solutions and determine the best one. Based on the results we have achieved through analysis, as well as pushing the manufacturing capabilities of 3D printers, we believe it is plausible to use additive manufacturing to create a fully capable vibration isolation system.


Tailoring Texture, Microstructure, And Shape Memory Behavior Of Niti Alloys Fabricated By L-Pbf-Am, Sayed Ehsan Saghaian N.E. Jan 2021

Tailoring Texture, Microstructure, And Shape Memory Behavior Of Niti Alloys Fabricated By L-Pbf-Am, Sayed Ehsan Saghaian N.E.

Theses and Dissertations--Mechanical Engineering

Laser Powder Bed Fusion (L-PBF) is one of the most promising Additive Manufacturing (AM) methods to fabricate near net-shape metallic materials for a wide range of applications such as patient-specific medical devices, functionally graded materials, and complex structures. NiTi shape memory alloys (SMAs) are of great interest due to a combination of unique features, such as superelasticity, shape memory effect, high ductility, work output, corrosion resistance, and biocompatibility that could be employed in many applications in automotive, aerospace, and biomedical industries. Due to the difficulties with traditional machining and forming of NiTi components, the ability to fabricate complex parts, tailor …


Numerical And Experimental Study Of Mechanical Properties For Laser Metal Deposition (Lmd) Process Part, Lan Li Jan 2021

Numerical And Experimental Study Of Mechanical Properties For Laser Metal Deposition (Lmd) Process Part, Lan Li

Doctoral Dissertations

"Laser Metal Deposition (LMD), also called as, Laser Engineered Net Shaping (LENS), Directed Energy Deposition (DED), is a typical Additive Manufacturing (AM) technology, is used for advanced free-form fabrication. It creates parts by directly melting materials and depositing them on the workpiece layer by layer. In this process, the metal powder or fiber is melted within the melting pool by laser beam or electron beam and quickly solidifies to the deposited layer. LMD technology shows great advantages over traditional manufacturing on complex structure fabrication, including high building rates, easy material replacement and reduced material waste. These merits make the wide …


Improvement Of Labyrinth Seal Leakage Rates Using Additive Manufacturing, Austin L. Gasbarra Dec 2020

Improvement Of Labyrinth Seal Leakage Rates Using Additive Manufacturing, Austin L. Gasbarra

Master's Theses

The growing popularity of additive manufacturing in commercial applications has al- lowed for new ideas and new ways of thinking when designing components. Further optimization at the component level is possible, though powder metallurgy is in its infancy. This study explores the possibility of using additive manufacturing to develop better labyrinth seals in turbomachinery. Labyrinth seals have a torturous fluid path with high losses, thus limiting the amount of fluid leakage. These types of seals can be non-rotating, allowing them to better take advantage of the additive manufacturing process due to the absence of rotating stresses. Labyrinth seal performance is …


Study On The Viability Of Preparing Plaster Molds For Rapid Prototyping Of Complex Ceramic Parts Using The Lost Pla Method, Shelton F. Fowler Iv Nov 2020

Study On The Viability Of Preparing Plaster Molds For Rapid Prototyping Of Complex Ceramic Parts Using The Lost Pla Method, Shelton F. Fowler Iv

Honors College Theses

In the field of metal casting, cast parts often require an internal cavity to be made to meet design requirements. Frequently, these interior surfaces are not manufacturable through standard machining processes, and even when possible, they would most likely involve expensive and time-consuming operations. In order to avoid these machining costs, expendable ceramic or sand cores are manufactured and placed into the mold to allow the direct casting of complex internal geometries. This research seeks to use relatively inexpensive plastic 3D printing technology and the lost PLA casting process for the production of low-cost and rapidly producible ceramic cores. A …


Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey Jan 2020

Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey

Browse all Theses and Dissertations

The presence of defects within laser powder bed fusion (LPBF) parts can lead to reduced mechanical properties and life of components. Because of this, the ability to detect these defects within the parts is critical before the part is subject to its intended loading. Normally the parts are subjected to a quality analysis once they are completed however, this process is typically expensive and time consuming. A solution for these problems is to sense the creation of defects and pores in the parts in-situ, while the part is being fabricated. One proposed method of in-situ monitoring is visible spectroscopy to …


Multi-Wavelength Pyrometry For Emissivity Mapping And Accurate Surface Temperature Measurement In Powder Bed Fusion Systems, Md Moinuddin Shuvo Jan 2020

Multi-Wavelength Pyrometry For Emissivity Mapping And Accurate Surface Temperature Measurement In Powder Bed Fusion Systems, Md Moinuddin Shuvo

Open Access Theses & Dissertations

Accurate surface temperature measurement within powder bed fusion (PBF) systems during fabrication remains elusive for many reasons, despite the importance of knowing temperature for improving part quality, process control, repeatability and reproducibility, simulation capabilities, and more. Multi-wavelength (MW) pyrometry has been used previously to measure off-axis temperatures of a small region (~2.6mm in diameter) within an electron beam PBF (EBPBF) system. While this small region measurement makes it difficult to get a full field temperature map of the powder bed, it also allows for inline (on-axis) with laser temperature measurements for laser PBF (LPBF) systems. The MW pyrometry technique determines …