Open Access. Powered by Scholars. Published by Universities.®

Materials Science and Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Michigan Technological University

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 31 - 60 of 265

Full-Text Articles in Materials Science and Engineering

Thermal Post-Processing Of 3d Printed Polypropylene Parts For Vacuum Systems, Pierce Mayville, Aliaksei L. Petsiuk, Joshua M. Pearce Sep 2022

Thermal Post-Processing Of 3d Printed Polypropylene Parts For Vacuum Systems, Pierce Mayville, Aliaksei L. Petsiuk, Joshua M. Pearce

Michigan Tech Publications

Access to vacuum systems is limited because of economic costs. A rapidly growing approach to reduce the costs of scientific equipment is to combine open-source hardware methods with digital distributed manufacturing with 3D printers. Although high-end 3D printers can manufacture vacuum components, again, the cost of access to tooling is economically prohibitive. Low-cost material extrusion 3D printing with plastic overcomes the cost issue, but two problems arise when attempting to use plastic in or as part of vacuum systems: the outgassing of polymers and their sealing. To overcome these challenges, this study explores the potential of using post-processing heat treatments …


Do Agrivoltaics Improve Public Support For Solar? A Survey On Perceptions, Preferences, And Priorities, Alexis Pascaris, Chelsea Schelly, Mark Rouleau, Joshua Pearce Aug 2022

Do Agrivoltaics Improve Public Support For Solar? A Survey On Perceptions, Preferences, And Priorities, Alexis Pascaris, Chelsea Schelly, Mark Rouleau, Joshua Pearce

Michigan Tech Publications

Agrivoltaic systems integrate agricultural production with solar photovoltaic electricity generation. Given the proven technical, economic, and environmental co-benefits provided by agrivoltaic systems, increased proliferation is anticipated, which necessitates accounting for the nuances of community resistance to solar development on farmland and identifying pathways for mitigation. Minimizing siting conflict and addressing agricultural communities’ concerns will be key in continued deployment of agrivoltaics, as localized acceptance of solar is a critical determinant of project success. This survey study assessed if public support for solar development increases when energy and agricultural production are combined in an agrivoltaic system. Results show that 81.8% of …


Utilization Of Bayesian Optimization And Kwn Modeling For Increased Efficiency Of Al‐Sc Precipitation Strengthening, Kyle Deane, Yang Yang, Joseph Licavoli, Vu Nguyen, Santu Rana, Sunil Gupta, Svetha Venkatesh, Paul G. Sanders Jun 2022

Utilization Of Bayesian Optimization And Kwn Modeling For Increased Efficiency Of Al‐Sc Precipitation Strengthening, Kyle Deane, Yang Yang, Joseph Licavoli, Vu Nguyen, Santu Rana, Sunil Gupta, Svetha Venkatesh, Paul G. Sanders

Michigan Tech Publications

The Kampmann and Wagner numerical model was adapted in MATLAB to predict the precipitation and growth of Al3Sc precipitates as a function of starting concentration and heat‐treatment steps. This model was then expanded to predict the strengthening in alloys using calculated average precipitate number density, radius, etc. The calibration of this model was achieved with Bayesian optimization, and the model was verified against experimentally gathered hardness data. An analysis of the outputs from this code allowed the development of optimal heat treatments, which were validated experimentally and proven to result in higher final strengths than were previously observed. Bayesian optimization …


Energy Science & Engineering: 10 Years Of Excellence, Yun Hang Hu May 2022

Energy Science & Engineering: 10 Years Of Excellence, Yun Hang Hu

Michigan Tech Publications

No abstract provided.


Ultrahigh Piezoelectric Performance Through Synergistic Compositional And Microstructural Engineering, Yongke Yan, L. D. Geng, Li Feng Zhu, Haoyang Leng, Xiaotian Li, Hairui Liu, Dabin Lin, Ke Wang, Yu Wang, Shashank Priya Mar 2022

Ultrahigh Piezoelectric Performance Through Synergistic Compositional And Microstructural Engineering, Yongke Yan, L. D. Geng, Li Feng Zhu, Haoyang Leng, Xiaotian Li, Hairui Liu, Dabin Lin, Ke Wang, Yu Wang, Shashank Priya

Michigan Tech Publications

Piezoelectric materials enable the conversion of mechanical energy into electrical energy and vice-versa. Ultrahigh piezoelectricity has been only observed in single crystals. Realization of piezoelectric ceramics with longitudinal piezoelectric constant (d33) close to 2000 pC N–1, which combines single crystal-like high properties and ceramic-like cost effectiveness, large-scale manufacturing, and machinability will be a milestone in advancement of piezoelectric ceramic materials. Here, guided by phenomenological models and phase-field simulations that provide conditions for flattening the energy landscape of polarization, a synergistic design strategy is demonstrated that exploits compositionally driven local structural heterogeneity and microstructural grain orientation/texturing to provide record piezoelectricity in …


Molecular Modeling Of High-Performance Polymers, Sagar Umesh Patil Jan 2022

Molecular Modeling Of High-Performance Polymers, Sagar Umesh Patil

Dissertations, Master's Theses and Master's Reports

High-performance polymers are extensively used in the aerospace and aeronautics industries due to their low density, high specific strength, and high specific stiffness. These properties along with better infiltration with reinforcements [carbon nanotubes (CNTs), glass, etc.] capability make them an excellent candidate to fabricate Polymer Matrix Composites (PMCs) tailored for specific applications. The applications range from products used daily to deep space exploration. These materials are subjected to varying temperatures and pressures during fabrication and in service. Therefore, the evolution of their intrinsic properties needs to be studied and their ability to sustain extreme environmental conditions in outer space needs …


Microscale Transverse Compression Modeling: A Comparative Study Of The Analytical Mac/Gmc Methods To Experimental Results, Emily Zeitunian Jan 2022

Microscale Transverse Compression Modeling: A Comparative Study Of The Analytical Mac/Gmc Methods To Experimental Results, Emily Zeitunian

Dissertations, Master's Theses and Master's Reports

Composite materials require a multi-scale approach to fully understand its behavior. At the micro level, material behavior analysis is conducted most often using numerical or analytical approaches. These models, however, require validation from experimental data to ensure material predictions are accurate. This study compares a semi-analytical micromechanical analysis tool, MAC/GMC, to experimental results of in-situ microscale transverse compression testing conducted at AFRL facilities. Effective properties, stress-strain curves, stress and strain fields, and damage predictions are compared with experimental outputs. Both generalized method of cells (GMC) and high-fidelity generalized method of cells (HFGMC) theories implemented within MAC/GMC show results that agree …


Length-Scale-Dependent Stress Relief Mechanisms In High Purity Indium, Fereshteh Mallakpour Jan 2022

Length-Scale-Dependent Stress Relief Mechanisms In High Purity Indium, Fereshteh Mallakpour

Dissertations, Master's Theses and Master's Reports

Lithium-ion batteries are widely used in portable electronics and electric vehicles. However, due to the presence of flammable liquid electrolytes, these devices fail catastrophically when the cell experiences a short circuit. One attractive solution to this problem is a solid-state battery. As the name implies, the flammable liquid electrolyte is replaced by a non-flammable solid-state electrolyte (SSE). The unexpected, yet frequently observed failure mechanism in these devices is the formation and growth of lithium dendrites originating at the interface between the lithium anode and the SSE. As the dendrites grow, device performance degrades. Once the dendrites completely penetrate the SSE, …


The Influence Of Different Crystal Modifiers On Ultra-Low Embodied Energy Curing Fiber-Reinforced Cement Composites, Passakorn Sonprasarn, Wichit Prakaypan, Sureerat Polsilapa, Nuntaporn Kongkajun, Edward A. Laitila, Nutthita Chuankrerkkul, Parinya Chakartnarodom Jan 2022

The Influence Of Different Crystal Modifiers On Ultra-Low Embodied Energy Curing Fiber-Reinforced Cement Composites, Passakorn Sonprasarn, Wichit Prakaypan, Sureerat Polsilapa, Nuntaporn Kongkajun, Edward A. Laitila, Nutthita Chuankrerkkul, Parinya Chakartnarodom

Michigan Tech Publications

Fiber-reinforced cement composites (FRCC) are widely used in the construction of houses and commercial buildings in many countries such as the United States, the United Kingdom, the European countries, and the Asian countries such as China, India, and Thailand. Conventionally, the FRCC is manufactured from Portland cement, silica sand, and cellulose fiber using the so-called autoclaved curing under a designate hydrothermal condition to accelerate the hydration reaction resulting in superior properties. However, the autoclave-curing process needs a huge investment and generates highly environmental impact specially greenhouse gases due to its heavy energy consumption. Hence, this research aims to develop the …


Bioabsorbable Metal Zinc Differentially Affects Mitochondria In Vascular Endothelial And Smooth Muscle Cells, Olivia R. M. Bagshaw, Fereshteh Moradi, Christopher S. Moffatt, Hillary A. Hettwer, Ping Liang, Jeremy Goldman, Jaroslaw Drelich, Jeffrey A. Stuart Dec 2021

Bioabsorbable Metal Zinc Differentially Affects Mitochondria In Vascular Endothelial And Smooth Muscle Cells, Olivia R. M. Bagshaw, Fereshteh Moradi, Christopher S. Moffatt, Hillary A. Hettwer, Ping Liang, Jeremy Goldman, Jaroslaw Drelich, Jeffrey A. Stuart

Michigan Tech Publications

Zinc is an essential trace element having various structural, catalytic and regulatory interactions with an estimated 3000 proteins. Zinc has drawn recent attention for its use, both as pure metal and alloyed, in arterial stents due to its biodegradability, biocompatibility, and low corrosion rates. Previous studies have demonstrated that zinc metal implants prevent the development of neointimal hyperplasia, which is a common cause of restenosis following coronary intervention. This suppression appears to be smooth muscle cell-specific, as reendothelization of the neointima is not inhibited. To better understand the basis of zinc's differential effects on rat aortic smooth muscle (RASMC) versus …


Life Cycle Assessment Of Pasture-Based Agrivoltaic Systems: Emissions And Energy Use Of Integrated Rabbit Production, Alexis Pascaris, Robert Handler, Chelsea Schelly, Joshua Pearce Dec 2021

Life Cycle Assessment Of Pasture-Based Agrivoltaic Systems: Emissions And Energy Use Of Integrated Rabbit Production, Alexis Pascaris, Robert Handler, Chelsea Schelly, Joshua Pearce

Michigan Tech Publications

Agrivoltaic systems, which deliberately maximize the utility of a single parcel of land for both solar photovoltaic (PV) electricity production and agriculture, have been demonstrated as a viable technology that can ameliorate competing land uses and meet growing energy and food demands efficiently. The goal of this study is to assess the environmental impacts of a novel pasture-based agrivoltaic concept: co-farming rabbits and solar PV. A life cycle assessment (LCA) quantified the impacts of 1) the integrated agrivoltaic concept in comparison to conventional practices including 2) separate rabbit farming and PV production and 3) separate rabbit farming and conventional electricity …


Degradation Issues And Stabilization Strategies Of Protonic Ceramic Electrolysis Cells For Steam Electrolysis, Hanrui Su, Yun Hang Hu Nov 2021

Degradation Issues And Stabilization Strategies Of Protonic Ceramic Electrolysis Cells For Steam Electrolysis, Hanrui Su, Yun Hang Hu

Michigan Tech Publications

Protonic ceramic electrolysis cells (PCECs) are attractive electrochemical de-vices for converting electrical energy to chemicals due to their high conversion efficiency, favorable thermodynamics, fast kinetics, and inexpensive materials. Compared with conventional oxygen ion- conducting solid oxide electrolysis cells, PCECs operate at a lower operating temperature and a favorable operation mode, thus expecting high durability. However, the degradation of PCECs is still significant, hampering their development. In this review, the typical degradations of PCECs are summarized, with emphasis on the chemical stability of the electrolytes and the air electrode materials. Moreover, the degradation mechanism and influencing factors are assessed deeply. Finally, …


Decarbonizing Rural Residential Buildings In Cold Climates: A Techno-Economic Analysis Of Heating Electrification, Filippo Padovani, Nelson Sommerfeldt, Francesca Longobardi, Joshua M. Pearce Nov 2021

Decarbonizing Rural Residential Buildings In Cold Climates: A Techno-Economic Analysis Of Heating Electrification, Filippo Padovani, Nelson Sommerfeldt, Francesca Longobardi, Joshua M. Pearce

Michigan Tech Publications

Given the need for decarbonization of the heating sector and the acute need of a propane replacement in the U.S. Upper Midwest, this study quantifies the techno-economic characteristics of sustainable heating electrification in isolated rural, residential buildings in cold climates without natural gas supply. Archetypal buildings are modeled under four levels of electrification. At each electrification level, a parametric solar photovoltaic (PV) sizing analysis is performed and the total life cycle cost, renewable fraction and greenhouse gas (GHG) emissions are calculated based on the primary energy supply for each building type. Cost optimal solutions are stress-tested with multi-dimensional sensitivity analyses. …


Research And Applications Of Artificial Neural Network In Pavement Engineering: A State-Of-The-Art Review, Xu Yang, Jinchao Guan, Ling Ding, Zhanping You, Vincent C.S. Lee, Mohd Rosli Mohd Hasan, Xiaoyun Cheng Oct 2021

Research And Applications Of Artificial Neural Network In Pavement Engineering: A State-Of-The-Art Review, Xu Yang, Jinchao Guan, Ling Ding, Zhanping You, Vincent C.S. Lee, Mohd Rosli Mohd Hasan, Xiaoyun Cheng

Michigan Tech Publications

Given the great advancements in soft computing and data science, artificial neural network (ANN) has been explored and applied to handle complicated problems in the field of pavement engineering. This study conducted a state-of-the-art review for surveying the recent progress of ANN application at different stages of pavement engineering, including pavement design, construction, inspection and monitoring, and maintenance. This study focused on the papers published over the last three decades, especially the studies conducted since 2013. Through literature retrieval, a total of 683 papers in this field were identified, among which 143 papers were selected for an in-depth review. The …


Mechanical Properties And Characterization Of Epoxy Composites Containing Highly Entangled As-Received And Acid Treated Carbon Nanotubes, Aaron Krieg, Julia A. King, Gregory M. Odegard, Timothy Leftwich, Leif K. Odegard, Paul D. Fraley, Ibrahim Miskioglu, Claire Jolowsky, Matthew Lundblad, Jin Gyu Park, Richard Liang Sep 2021

Mechanical Properties And Characterization Of Epoxy Composites Containing Highly Entangled As-Received And Acid Treated Carbon Nanotubes, Aaron Krieg, Julia A. King, Gregory M. Odegard, Timothy Leftwich, Leif K. Odegard, Paul D. Fraley, Ibrahim Miskioglu, Claire Jolowsky, Matthew Lundblad, Jin Gyu Park, Richard Liang

Michigan Tech Publications

Huntsman–Merrimack MIRALON® carbon nanotubes (CNTs) are a novel, highly entan-gled, commercially available, and scalable format of nanotubes. As-received and acid-treated CNTs were added to aerospace grade epoxy (CYCOM® 977-3), and the composites were characterized. The epoxy resin is expected to infiltrate the network of the CNTs and could improve mechanical properties. Epoxy composites were tested for flexural and viscoelastic properties and the as-re-ceived and acid treated CNTs were characterized using Field-Emission Scanning and Transmission Electron Microscopy, X-Ray Photoelectron Spectroscopy, and Thermogravimetric Analysis. Composites containing 0.4 wt% as-received CNTs showed an increase in flexural strength, from 136.9 MPa for neat epoxy …


A Xanes Study Of Lithium Polysulfide Solids: A First-Principles Study, Qing Guo, Kah Chun Lau, Ravindra Pandey Aug 2021

A Xanes Study Of Lithium Polysulfide Solids: A First-Principles Study, Qing Guo, Kah Chun Lau, Ravindra Pandey

Michigan Tech Publications

X-ray absorption spectroscopy (XAS) is used for capturing the reaction mechanisms at the molecular level via the determination of local electronic configurations inside Li-S batteries. In this paper, a comprehensive investigation of the S K-edge X-ray absorption near-edge structure (XANES) of a series of stoichiometric lithium polysulfide solids was performed, assuming that these polysulfide solids are formed during the battery cycling process. The results based on density functional theory show that the pre-edge peak in the S K-edge XANES spectra is not a common feature in the solid phase in contrast to the case of pristine polysulfide molecules where the …


Open Source Vacuum Oven Design For Low-Temperature Drying: Performance Evaluation For Recycled Pet And Biomass, Benjamin R. Hubbard, Lindsay I. Putman, Stephen Techtmann, Joshua M. Pearce May 2021

Open Source Vacuum Oven Design For Low-Temperature Drying: Performance Evaluation For Recycled Pet And Biomass, Benjamin R. Hubbard, Lindsay I. Putman, Stephen Techtmann, Joshua M. Pearce

Michigan Tech Publications

Vacuum drying can dehydrate materials further than dry heat methods, while protecting sensitive materials from thermal degradation. Many industries have shifted to vacuum drying as cost-or time-saving measures. Small-scale vacuum drying, however, has been limited by the high costs of specialty scientific tools. To make vacuum drying more accessible, this study provides design and performance information for a small-scale open source vacuum oven, which can be fabricated from off-the-shelf and 3-D printed components. The oven is tested for drying speed and effectiveness on both waste plastic polyethylene terephthalate (PET) and a consortium of bacteria developed for bioprocessing of terephthalate wastes …


Supporting Materials From The Program "Development Of A Physically-Based Creep Model Incorporating Eta Phase Evolution For Nickel Base Superalloys", N. R. Mohale, C. L. White, P. G. Sanders, W. W. Milligan, J. P. Shingledecker, P. A. Bridges May 2021

Supporting Materials From The Program "Development Of A Physically-Based Creep Model Incorporating Eta Phase Evolution For Nickel Base Superalloys", N. R. Mohale, C. L. White, P. G. Sanders, W. W. Milligan, J. P. Shingledecker, P. A. Bridges

Michigan Tech Research Data

This research was funded by the US Department of Energy, Fossil Energy Program, Grant Number DE-FE0027822, with Omer Bakshi as the Program Manager. The grant conditions required that all supporting data and materials would be made publicly-available. This public repository was created on May 13, 2021.


U.S. Potential Of Sustainable Backyard Distributed Animal And Plant Protein Production During And After Pandemics, Theresa K. Meyer, Alexis Pascaris, David Denkenberger, Joshua M. Pearce Apr 2021

U.S. Potential Of Sustainable Backyard Distributed Animal And Plant Protein Production During And After Pandemics, Theresa K. Meyer, Alexis Pascaris, David Denkenberger, Joshua M. Pearce

Michigan Tech Publications

To safeguard against meat supply shortages during pandemics or other catastrophes, this study analyzed the potential to provide the average household’s entire protein consumption using either soybean production or distributed meat production at the household level in the U.S. with: (1) pasture-fed rabbits, (2) pellet and hay-fed rabbits, or (3) pellet-fed chickens. Only using the average backyard resources, soybean cultivation can provide 80-160% of household protein and 0- 50% of a household’s protein needs can be provided by pasture-fed rabbits using only the yard grass as feed. If external supplementation of feed is available, raising 52 chickens while also harvesting …


Open Source 3d-Printable Planetary Roller Screw For Food Processing Applications, Marcello C. Guadagno, Jacob M. Loss, Joshua M. Pearce Apr 2021

Open Source 3d-Printable Planetary Roller Screw For Food Processing Applications, Marcello C. Guadagno, Jacob M. Loss, Joshua M. Pearce

Michigan Tech Publications

Historically, open source agriculture (OSA) was based on grassroots technology generally manufactured by hand tools or with manual machining. The rise of distributed digital manufacturing provides an opportunity for much more rapid lateral scaling of open source appropriate technologies for agriculture. However, the most mature distributed manufacturing area is plastic, which has limited use for many OSA applications. To overcome this limitation with design, this study reports on of a completely 3D-printable planetary roller screw linear actuator. The device is designed as a parametric script-based computer aided design (CAD) package to allow for the easy adaption for a number of …


Authors From All Over The World Share Their Tech In Hardwarex To Battle Covid-19, Joshua M. Pearce Apr 2021

Authors From All Over The World Share Their Tech In Hardwarex To Battle Covid-19, Joshua M. Pearce

Michigan Tech Publications

No abstract provided.


Origin Of Magnetism In Γ-Fesi 2 /Si(111) Nanostructures, Liwei D. Geng, Sahil Dhoka, Ilan Goldfarb, Ranjit Pati, Yongmei M. Jin Mar 2021

Origin Of Magnetism In Γ-Fesi 2 /Si(111) Nanostructures, Liwei D. Geng, Sahil Dhoka, Ilan Goldfarb, Ranjit Pati, Yongmei M. Jin

Michigan Tech Publications

Magnetism has recently been observed in nominally nonmagnetic iron disilicide in the form of epitaxial γ-FeSi2 nanostructures on Si(111) substrate. To explore the origin of the magnetism in γ-FeSi2/Si(111) nanostructures, we performed a systematic first-principles study based on density functional theory. Several possible factors, such as epitaxial strain, free surface, interface, and edge, were examined. The calculations show that among these factors, only the edge can lead to the magnetism in γ-FeSi2/Si(111) nanostructures. It is shown that magnetism exhibits a strong dependency on the local atomic structure of the edge. Furthermore, magnetism can be enhanced by creating multiple-step edges. In …


Highly Efficient Visible-Light Photocatalytic Ethane Oxidation Into Ethyl Hydroperoxide As A Radical Reservoir, Yao Zhu, Siyuan Fang, Shaoqin Chen, Youjie Tong, Chunling Wang, Yun Hang Hu Mar 2021

Highly Efficient Visible-Light Photocatalytic Ethane Oxidation Into Ethyl Hydroperoxide As A Radical Reservoir, Yao Zhu, Siyuan Fang, Shaoqin Chen, Youjie Tong, Chunling Wang, Yun Hang Hu

Michigan Tech Publications

Photocatalytic ethane conversion into value-added chemicals is a great challenge especially under visible light irradiation. The production of ethyl hydroperoxide (CH CH OOH), which is a promising radical reservoir for regulating the oxidative stress in cells, is even more challenging due to its facile decomposition. Here, we demonstrated a design of a highly efficient visible-light-responsive photocatalyst, Au/WO , for ethane oxidation into CH CH OOH, achieving an impressive yield of 1887 μmol g in two hours under visible light irradiation at room temperature for the first time. Furthermore, thermal energy was introduced into the photocatalytic system to increase the driving …


Progress In Proton-Conducting Oxides As Electrolytes For Low-Temperature Solid Oxide Fuel Cells: From Materials To Devices, Wei Zhang, Yun Hang Hu Mar 2021

Progress In Proton-Conducting Oxides As Electrolytes For Low-Temperature Solid Oxide Fuel Cells: From Materials To Devices, Wei Zhang, Yun Hang Hu

Michigan Tech Publications

Among various types of alternative energy devices, solid oxide fuel cells (SOFCs) operating at low temperatures (300-600°C) show the advantages for both stationary and mobile electricity production. Proton-conducting oxides as electrolyte materials play a critical role in the low-temperature SOFCs (LT-SOFCs). This review summarizes progress in proton-conducting solid oxide electrolytes for LT-SOFCs from materials to devices, with emphases on (1) strategies that have been proposed to tune the structures and properties of proton-conducting oxides and ceramics, (2) techniques that have been employed for improving the performance of the protonic ceramic-based SOFCs (known as PCFCs), and (3) challenges and opportunities in …


Economics Of Grid-Tied Solar Photovoltaic Systems Coupled To Heat Pumps: The Case Of Northern Climates Of The U.S. And Canada, Joshua M. Pearce, Nelson Sommerfeldt Feb 2021

Economics Of Grid-Tied Solar Photovoltaic Systems Coupled To Heat Pumps: The Case Of Northern Climates Of The U.S. And Canada, Joshua M. Pearce, Nelson Sommerfeldt

Michigan Tech Publications

Solar photovoltaic (PV) technology is now a profitable method to decarbonize the grid, but if catastrophic climate change is to be avoided, emissions from transportation and heating must also decarbonize. One approach to renewable heating is leveraging improvements in PV with heat pumps (HPs). To determine the potential for PV+HP systems in northern areas of North America, this study performs numerical simulations and economic analysis using the same loads and climate, but with local electricity and natural gas rates for Sault Ste. Marie, in both Canada and U.S. Ground-mounted, fixed-tilt, grid-tied PV systems are sized to match 100% of electric …


Gas Measurement Device, Megan C. Frost, Weilue He Jan 2021

Gas Measurement Device, Megan C. Frost, Weilue He

Michigan Tech Patents

A device including a first chamber, a second chamber, and a membrane permeable to neutral gases but impermeable to water that is positioned between the first chamber and the second chamber. The membrane includes a first layer including PVDF and PDMS, and the PVDF has a plurality of pores at least partially filled with at least some of the PDMS.


Deformation Manifold Learning Model For Multi Walled Carbon Nanotubes, Shashank S. Pathrudkar Jan 2021

Deformation Manifold Learning Model For Multi Walled Carbon Nanotubes, Shashank S. Pathrudkar

Dissertations, Master's Theses and Master's Reports

Two-Dimensional (2D) materials are being studied widely by researchers due to their superior material properties over the bulk materials. Since the isolation of graphene in 2004, graphene has gained popularity amongst the 2D materials community. Graphene when rolled into sheets form Carbon Nanotubes (CNTs) which possess excellent mechanical and electrical properties. Concentric stacks of CNTs yield Multi-walled Carbon Nanotubes (MWCNTs) which are superior to CNTs in certain aspects. It has been well established that the deformation of CNTs and MWCNTs change their mechanical and electrical properties significantly. This has opened doors for CNTs into numerous applications and also piqued the …


Thermomechanical Mechanisms That Cause Adhesion Of Aluminum High Pressure Die Castings To The Die, Alex Monroe Jan 2021

Thermomechanical Mechanisms That Cause Adhesion Of Aluminum High Pressure Die Castings To The Die, Alex Monroe

Dissertations, Master's Theses and Master's Reports

In high pressure die casting (HPDC) of aluminum, cast material adhering to die is a significant defect. Adhesion occurs in two primary ways. The casting may stick preventing its removal from the die. Aluminum can also adhere to the die and buildup in local areas on the die surface with additional casting cycles. This second form of adhesion is called soldering. Lubricant is the best technology to control all forms of adhesion, but it comes at the cost of casting porosity, blisters, reduced die life, and increased die casting machine wear. New strategies to prevent adhesion are desired to eliminate …


The Effects Of Molybdenum, Chromium, And Niobium On Gray Iron For Brake Rotor Applications, Matthew Hasbrouck Jan 2021

The Effects Of Molybdenum, Chromium, And Niobium On Gray Iron For Brake Rotor Applications, Matthew Hasbrouck

Dissertations, Master's Theses and Master's Reports

Brake rotor composition and microstructure must be optimized for thermal and mechanical performance to avoid thermal-mechanical cracking, excessive wear, and to reduce noise. Niobium is an element that increases the strength and wear resistance of gray iron; however, the interaction of niobium with other common alloying elements (chromium and molybdenum) is not well understood. Thirteen gray cast iron alloys were produced with varying levels of carbon equivalent (CE), Cr, Mo, and Nb. Bars with four different diameters (8, 14, 22, and 30 mm) were cast from each alloy and microstructural and physical properties such as graphite flake morphology, pearlite spacing, …


Atomistic Monte Carlo Simulation Study Of Phase Transitions In Metal Alloys, Xiaoxu Guo Jan 2021

Atomistic Monte Carlo Simulation Study Of Phase Transitions In Metal Alloys, Xiaoxu Guo

Dissertations, Master's Theses and Master's Reports

The atomic-scale Monte Carlo simulation study focuses on the intrinsic behaviors of a defect-free crystal that undergoes a cubic-to-tetragonal martensitic transformation. The quasi-spin variable associated with the lattice sites characterizes the local unit cells of the orientation variants of the ground-state martensite phase, which interact with each other through long-range elastic interactions. It is shown that the diffuse scattering in the premartensitic austenite state results from the spatial correlation of the atomic-scale heterogeneous lattice displacements and manifests the displacement short-range ordering. The effects of temperature, elastic anisotropy, and shear modulus softening on the diffuse scattering and displacement short-range ordering are …