Materials Science and Engineering Commons^™

Moisture Effects On Visible Near-Infrared And Mid-Infrared Soil Spectra And Strategies To Mitigate The Impact For Predictive Modeling, Francis Hettige Chamika Anuradha Silva

Theses and Dissertations

Instrumental disparities and soil moisture are two of the key limitations in implementing spectroscopic techniques in the field. This study sought to address these challenges through two objectives. The first objective was to assess Visible-near infrared (VisNIR) and mid-infrared (MIR) spectroscopic approaches and explore the feasibility of transferring calibration models between laboratory and portable spectrometers. The second objective addressed the challenge of soil moisture and its impact on spectra. The portable spectrometers demonstrated comparable performance to their laboratory-based counterparts in both regions. Spiking with extra-weight, was the most effective calibration transfer method eliminating disparities between instruments. The samples were rewetted …

Cobalt Chromium In Biomedical Applications And The Development Of A Pspp Map, Nouralhouda Jamal

Bagley College of Engineering Publications and Scholarship

During the world wars, Cobalt-Chromium (Co-Cr) alloys gained prominence for their use in aircraft engine components, where they exhibited high temperature strength and durability. They are used in a wide range of industries due to their unique set of qualities, particularly strength, corrosion resistance, and biocompatibility. They have emerged as versatile materials with a broad spectrum of applications, from aerospace and automotive components to biomedical implants.

This paper presents a thorough analysis of its composition, processing techniques, microstructure, mechanical properties, and performance characteristics. The primary goal of this project is to develop a PSPP (Process, structure, properties, and performance) map …

Elucidating Self-Assembly Of Semiconducting Polymers In The Presence Of A Low Molecular Weight Gelator, Madhubhashini Lakdusinghe

Theses and Dissertations

Semiconducting polymers with a conjugated backbone are important for energy storage, conversion, and biomedical field applications. The self-assembly process of these polymers in solutions depends on the polymer concentration and quality of the solvent. The electrical properties of thin films obtained from the solution phase depend on the self-assembled process. Thin films of conjugated polymer gels with percolating networks of self-assembled structures display improved electrical conductivities. In this dissertation, we studied the impact of the secondary gel matrix formed by a low molecular weight gelator, on the self-assembly of conjugated polymers, the preservation of assembled structures in dried gel films …

Development Of Preservative-Treated Cross-Laminated Timber And Lignin-Reinforced Polyurethane-Adhesive For Glued Laminated Timber, Samuel Oluwafemi Ayanleye

Theses and Dissertations

Interest in the use of mass timber in building and construction is growing worldwide, this is due to the structural integrity and reduced environmental footprint of timber-based structures. Concerns associated with the biological and environmental degradation of mass timber necessitate the development of adequate protection strategies to ensure the durability of these products. Preservative treatment is a proven technique that increases the durability and performance of wood in-service and can also be applied to large-sized timber panels such as cross-laminated timber (CLT). Therefore, this study focused on investigating the feasibility of treating prefabricated 3- and 5-layer CLT panels with Copper-azole …

Integrating Steel Slag Aggregates Into Asphalt Paving By Harmonizing Availability, Quality, Economics, And The Environment, Timothy R. Murphy

Theses and Dissertations

This thesis provides guidance on how to balance matters related to the environmental stewardship, market sources, origin and uses, material properties, performance, and economic impact of using slag materials in pavements. The literature on this topic provides numerous references on the use of slag materials for specific applications, and this thesis aims to make use of those references along with other data from the author to describe slag materials from a holistic perspective and provide some suggestions for balancing several factors that impact optimal use of this resource within pavement structures. Discussion is given to the increased importance of recycling …

A Constitutive Material Model For Simulating Texture Evolution And Anisotropy Effects In Cold Spray., Creston Michael Giles

Theses and Dissertations

Cold spray has seen rapid advancement since its inception and has shown significant potential as a method of additive manufacturing. However, the large plastic deformation and repeated heating/cooling cycles that the material undergoes during the cold spray process can result in gradients in material structure and large residual stresses. The purpose of this study is to extend the existing EMMI material model to include anisotropic material response through the use of orientation distribution functions to predict residual stresses and anisotropy resulting from cold spray and similar additive manufacturing processes. Through the use of a finite element simulation, yield surfaces for …

Platinum-Iridium Alloys In Jewelry, Nathen C. Christa, Seth Walker, Dylan Hallman

ME 4133/6133 Mechanical Metallurgy

One of the most widely used metals on the periodic table is Platinum (Pt). The name is derived from the Spanish Platina, meaning “silver.” This malleable, ductile material is widely used in applications due to its unique chemical properties. A couple of these unique properties include a high melting point and good resistance to corrosion or chemical attack. Platinum materials have alloys that are indispensable in the chemical laboratory for electrodes. This allows for material applications in crucibles and dishes to withstand elevated temperatures. Platinum is used primarily in catalytic converters in vehicles converting emissions from the vehicle’s engine into …

High-Carbon Steel In Additive Manufacturing, Chidi N. Agusiegbe, Devin Morton, Emmanuel Moore

ME 4133/6133 Mechanical Metallurgy

High-carbon steel can be processed through numerous methods. The method that will be focused on primarily is processing high-carbon steel through means of additive manufacturing. Additive manufacturing is the industrial production name for 3D printing, a computer-controlled process that creates three-dimensional objects by depositing materials, usually in layers. AM methods like wire laser additive manufacturing (WLAM) and electron beam melting (EBM) are all common methods for fabricating high carbon steel. The perks associated with these methods are that they improve some drawbacks of the natural properties of high-carbon steel. This paper discusses the uses of these additive manufacturing methods along …

High Carbon Steel In Additive Manufacturing, Emmanuel Moore Ii, Devin Morton, Chid Agusiegbe

ME 4133/6133 Mechanical Metallurgy

The first known use of carbon steel dates back to 500 A.D. when a blacksmith mistakenly used iron ore as a primary material for smithing. This material, as the name suggests, is made up of both carbon and iron. This material, as one of the most abundant at the time, was used most frequently in European and Asian countries. “Carbon steel first appeared around the year 500 AD in Damascus steel swords as well as Japanese swords. They were prized for their sharp edges and sturdiness compared to other weapons of the era. The composition of these swords was very …

Integration Of Hadfield Steel Into Modern Body Armor, Jason T. Fridlund

ME 4133/6133 Mechanical Metallurgy

The increased lethality of recently fielded projectiles mandates a proportional escalation in armor performance. Recent advancements in ceramic technologies have allowed designers to incorporate harder but more brittle materials into hard armor designs to defeat yet more capable penetrating projectiles. Ceramics suffer from the feature of shattering, however, even when impacted by threats below their design parameters. While this shattering mechanism is used effectively to dissipate energy from high-energy rifle projectiles, it is wasted on low-energy projectiles, and can result in easily damaged lifesaving gear, both of which are undesirable in combat. In contrast, steel body armor has been used …

High Carbon Steel In Additive Manufacturing, Chidi Agusiegbe, Devin Morton, Emmanuel Moore

ME 4133/6133 Mechanical Metallurgy

Infographic demonstrating the composition, and use of high carbon steels as well as the process of the material in additive manufacturing.

Sae 8620 Pspp Map - Infographic, John F. Mitchener

ME 4133/6133 Mechanical Metallurgy

This infographic summarizes a Processing-Structure-Property-Performance (PSPP) Map for SAE 8620 alloy steel, with an emphasis on the gas carburization process. This PSPP map allows researchers and material scientists to better understand the processes that drive the microstructures, material properties, and ultimate performance parameters.

Effects Of Cyclic Intercritical Annealing On Strength-Ductility Combinations In Medium Manganese Steels, Dawn Van Iderstine

Theses and Dissertations

Intercritically annealed medium manganese steels are a promising third-generation advanced high-strength steel candidate, relying on large fractions of Mn-enriched retained austenite for excellent strength-ductility combinations. The present study proposes a novel cyclic intercritical annealing to promote nucleation and efficient stabilization of austenite in a medium Mn microstructure. Design of the heat treatment is driven by the hypothesis that the distribution of ductile austenite is key in mitigating the strain incompatibility that accelerates failure in these steels. Development and preliminary testing of the heat treatment are first detailed and compared with literature results for equivalent isothermal annealing. The effects of cyclic …

Ferrous Alloy Manufacturing For The Martian Surface Through In-Situ Resource Utilization With Ionic Liquids Harvested Iron And Bosch Process Carbon, Blake C. Stewart

Theses and Dissertations

As research continues for the habitation of the Lunar and Martian surfaces, the need for materials for construction of structural parts, mechanical components, and tools remains as a major milestone. The use of in-situ resource utilization (ISRU) techniques is critical due to the financial, physical, and logistical burdens of sending supplies beyond low-Earth orbit. The Bosch process is currently in development as a life support system at the National Aeronautics and Space Administration’s (NASA) Marshall Space Flight Center (MSFC) to regenerate oxygen (O2) from metabolic carbon dioxide (CO2) with the byproduct of elemental carbon (C). The Bosch process presents a …

A Modular Synthesis Of Processable And Thermally Stable Semi-Fluorinated Aryl Ether Polymers Via Step-Growth Polymerization Of Fluoroalkenes, Ketki Eknath Shelar

Theses and Dissertations

Tailored fluoropolymers remain the leading choice for a wide variety of advanced high-performance applications, including electronic/optical and energy conversion, owing to their unique blend of complementary high-performance properties. Amorphous semi-fluorinated polymers exhibit improved solubility and melt processability when compared to traditional perfluoropolymers. A leading class of semi-fluorinated aryl ether polymers includes perfluorocyclobutyl (PFCB), perfluorocycloalkenyl (PFCA), and fluoroarylene vinylene ether (FAVE) polymers. Monomers containing aromatic trifluorovinyl ethers (TFVE) are used to synthesize PFCB polymers via radical-mediated [2+2] cyclodimerization. On the other hand, FAVE and PFCA polymers are polymerized via base-mediated nucleophilic addition/elimination of bisphenols with TFVE monomers and decafluorocyclohexene respectively. The …

Phase-Field Simulations Of The Precipitation Kinetics And Microstructure Development In Nickel-Based Superalloys, Caleb O. Yenusah

Theses and Dissertations

The continual research and development of nickel-based superalloys is driven by the global demand to improve efficiency and reduce emissions in the aerospace and power generation industries. Integrated Computational Material Engineering (ICME) is a valuable tool for reducing the cost, time, and resources necessary for the development and optimization of the mechanical properties of materials. In this work, an ICME approach for understanding the microstructure development and optimizing the mechanical properties in nickel-based superalloys is employed. Most nickel-based superalloys are precipitate strengthened by either the γ’ phase, γ” phase, or both. Therefore, understanding the precipitation kinetics and morphological evolution of …

Challenges And Signal Processing Of High Strain Rate Mechanical Testing, Barae Lamdini

Theses and Dissertations

Dynamic testing provides valuable insight into the behavior of materials undergoing fast deformation. During Split-Hopkinson Pressure Bar testing, stress waves are measured using strain gauges as voltage variations that are usually very small. Therefore, an amplifier is required to amplify the data and analyze it. One of the few available amplifiers designed for this purpose is provided by Vishay Micro-Measurements which limits the user’s options when it comes to research or industry. Among the challenges of implementing the Hopkinson technology in the industry are the size and cost of the amplifier. In this work, we propose a novel design of …

Electromechanical Fatigue Properties Of Dielectric Elastomer Stretch Sensors Under Orthopaedic Loading Conditions, Andrea Karen Persons

Theses and Dissertations

Fatigue testing of stretch sensors often focuses on high amplitude, low-cycle fatigue (LCF) behavior; however, when used for orthopaedic, athletic, or ergonomic assessments, stretch sensors are subjected to low amplitude, high-cycle fatigue (HCF) conditions. As an added layer of complexity, the fatigue testing of stretch sensors is not only focused on the life of the material comprising the sensor, but also on the reliability of the signal produced during the extension and relaxation of the sensor. Research into the development of a smart sock that can be used to measure the range of motion (ROM) of the ankle joint during …

Characterization Of Hydrogen Embrittlement Sensitivity In High Hardness Steels, David Ahlen Salley

Theses and Dissertations

High hardness steels can be affected by delayed brittle cracking often attributed to hydrogen embrittlement. Improved resistance to hydrogen embrittlement would be beneficial to many industries including military, automotive, and high-rise construction. While other prevention methods include coating, trapping, and barriers, design efforts in this study were focused on improving intrinsic properties to be more resistant to hydrogen embrittlement. Four alloys targeting 477 – 534 HB were designed and produced in-house and compared against a commercial grade 500 HB alloy. Charpy V-notch (CVN) impact toughness and tensile specimens were made according to ASTM E23 and ASTM E8 to characterize mechanical …

Predictive Computational Materials Modeling With Machine Learning: Creating The Next Generation Of Atomistic Potential Using Neural Networks, Mashroor Shafat Nitol

Theses and Dissertations

Machine learning techniques using artificial neural networks (ANNs) have proven to be effective tools to rapidly mimic first principles calculations. These tools are capable of sub meV/atom accuracy while operating with linear scaling with respect to the system size. Here novel interatomic potentials are constructed based on the rapid artificial neural network (RANN) formalism. This approach generates precise force fields for various metals that have historically been difficult to describe at the atomic scale. These force fields can be utilized in molecular dynamics simulations to provide new physical insights. The RANN formalism, which is incorporated into a LAMMPS molecular dynamics …

Effects Of Bonding Pressure And Lamina Thickness On Mechanical Properties Of Clt Composed Of Southern Yellow Pine, Cody S. Bates

Theses and Dissertations

This study produced cross-laminated timber panels at a range of four lamina thickness (5/8, 1, 1 1/8, and 1 1/4 inch) and three bonding pressures (50, 125, 200 psi), producing a total of 12 panels for mechanical testing. The goal of this study is to observe how the thickness and pressure trends affect the mechanical properties of CLT. Tests include flatwise bending, flatwise shear, internal-bond, and delamination. Results showed that bending MOE decreases as the panel thickness increases while bonding pressure had no significance. Bending MOR was less significant for the thickness and more significant for pressure compared to the …

Study Of Alloy And Process Modifications To Design Hydrogen Resilient High Hardness Steels, William R. Williams

Theses and Dissertations

High hardness steels (HHS) are vulnerable to hydrogen embrittlement, which can lead to rapid degradation of mechanical properties. Improved resistance to hydrogen embrittlement would be beneficial to many industries including construction, automotive, and military. A comparison study was performed to assess the hydrogen susceptibility of select commercially available and in-house designed HHS alloys. Slow strain rate tensile tests, performed with specimens charged with various levels of hydrogen, provided a macroscopic view of the onset of hydrogen embrittlement. Hydrogen permeation and thermal desorption spectroscopy tests determined the uptake and diffusivity of hydrogen through the material. The evaluation of hydrogen susceptibility for …

The Process-Structure-Property-Performance Of Aisi 1020​, Jonathan Wellman, Tate James, Robbie Christman, Brian Broom

ME 4133/6133 Mechanical Metallurgy

AISI 1020 is widely used in many different industries due to its high strength, high ductility, high machinability, and good weldability. AISI 1020 has a number of applications. Low carbon steel can be used on a macroscale to build bridges, and low carbon steel can be used on smaller scales such as Lawnmower blades. Low carbon steel is the material of choice for lawn mower blades because of its ability to bend before it breaks. The ductile attribute of low carbon steel also has many other benefits.

Ti-6al-7nb Utilization In Surgical Implants, Michael O. Fleming

ME 4133/6133 Mechanical Metallurgy

This presentation discusses the processing, structure, properties, and performance of Ti-6Al-7Nb in relation to use as a surgical implant.

Development Of Pspp Map For Stainless Steel Alloys Used In A Marine Environment, Jarrett D. Hawkins

ME 4133/6133 Mechanical Metallurgy

A process-structure-properties-performance map will be created for these alloys focusing on the modification of the structure or composition and outlining the processes required and the affected properties. A thorough review of different chemical alloys, grain refining methods, and grain boundary compositions for several alloys and their corresponding property effects. Also plan to review material treatment processes and standard refining methods for stainless steels. The performance of these metals will be evaluated for property requirements in regards to strength, toughness, with an emphasis on corrosion resistance.

Tungsten: The Strongest Natural Metal On Earth, Haley E. Holland, Razan Khadka, Lee Marble, Kaleb Tutor

ME 4133/6133 Mechanical Metallurgy

The overall objective of this project was to construct a process-structure-property-performance (PSPP) map for a chosen metallic material. The material chosen by the group is tungsten (W). Tungsten is a rare, naturally occurring element and is usually found in the form of ores. It is known predominantly for its ability to withstand extreme temperatures, as well as its high tensile strength. The PSPP map displays many specifications of tungsten in each of the four categories and further details regarding each specific linkage, or subcategory, within the map are written throughout the research paper.

Along with the four specific categories outlined …

Analysis Of Titanium Alloy Ti-6al-4v, Hunter C. Smith, Gordin Smith

ME 4133/6133 Mechanical Metallurgy

Titanium alloy Ti-6Al-4V was chosen for examination, more specifically, the Properties and Performance of the alloy. The students will share the responsibility of examining the attributes of the material. The team members participate evenly in performing research, producing calculations, and constructing the final report. Contained herein is the information gathered through research conducted thus far.

The performance of the material will be related to the processing methods of the material. This relationship forms the basis of cost analysis. The students will examine the atomic characteristics and crystalline structure to determine the effects of the alloyed materials on properties such as …

An Analysis Of The Effects Of Process, Structure, And Properties On The Performance Of The Ti6al4v Alloy, Brad Jay Sampson, Loubna Ifqir

ME 4133/6133 Mechanical Metallurgy

Ti6Al4V (pronounced Ti-64), is a titanium alloy used in a variety of engineering applications including the aerospace, automotive, and biomedical industries. Ti6Al4V is made up of a combined ɑ-β microstructure, which provides it with many valuable properties such as high strength, low weight, high melting point, corrosion resistance, and biocompatibility. [1] For years, casting and forging have been the traditional processes used for the manufacturing of Ti6Al4V components, but recent interest in the additive manufacturing of Ti6Al4V through the Electron Beam Melting (EBM), Selective Laser Melting (SLM), and Directed Energy Deposition (DED) methods has been gained. The goal of this …

Al 6061 Alloy, Will Mckelvey, Evan Robertson, Justin Yates

ME 4133/6133 Mechanical Metallurgy

We want to portray the Al 6061 manufacturing and machining processes and how these affect the mechanical properties of the material. We also want to portray the strength and weaknesses and the reasons why it is used in certain applications.

Duplex Stainless Steel 2205 In The Pulp And Paper Industry, Charlie S. Wilcher, Trevor Davus

ME 4133/6133 Mechanical Metallurgy

Duplex stainless steel’s durability, formability, and resistance to corrosion make it the primary steel option of the pulp and paper industry. The harsh environments found in certain aspects of this industry, such as in bleach plants, digesters, liquor vessels, and any piping where corrosive liquids may be passed, require the previously mentioned properties that duplex stainless steel 2205 offer. The structure and properties of duplex stainless steel, as well as the processes it undergoes, allow for it to withstand these environments. Research into the structure and properties of duplex stainless steel and the processes it undergoes will indicate how duplex …