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This thesis document outlines the construction of a device for preparation of cylindrical ice-aluminum specimens. These specimens are for testing in a uniaxial load cell with the goal of determining properties of the ice-metal interface, as part of research into spray ice material properties and how such ice might be better removed from maritime vessels operating in sub-freezing temperatures. The design of the sample preparation device is outlined, justifications for design and component choices given and discussion of the design process and how problems which arose were tackled are included. Water is piped into the device through the freezers lid and sprayed by a full cone misting nozzle onto an aluminum sample rod. The sample rod is supported with Ultra High Molecular Weight Polyethylene pillars which allow for free rotation. A motor, timing belt and pulley assembly is used to rotate this metal rod at 1.25 RPM. The final device produces samples though intermittent flow in a 5 minutes on, 20 minutes off cycle. This intermittent flow is controlled through the use of a solenoid valve which is wired into the compressor. When the thermostat detects that the freezer is too warm, the compressor kicks on and the flow of water is stopped. Additional modifications to the freezer unit include the addition of a fan to cool the compressor during device operation. Recommendations are provided towards the end of the thesis, including suggestions to change the device to allow for constant flow and that deionized water be used instead of tap water due to hard water concerns.
ContributorsBaker, Dylan Paul (Author) / Oswald, Jay (Thesis director) / Yekani Fard, Masoud (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Carbon nanotube (CNT) membranes (buckypaper) are manufactured with multiple procedures, vacuum filtration, surfactant-free, and 3D printing. A post-manufacturing process for resin impregnation is subjected to the membranes. The effects of manufacturing processes on the microstructure and material properties are investigated for both pristine and resin saturated samples manufactured using all procedures. Microstructural characteristics that are studied include specific surface area, porosity, pore size distribution, density, and permeability. Scanning electron microscopy is used to characterize the morphology of the membrane. Brunauer-Emmett-Teller analysis is conducted on membrane samples to determine the specific surface area. Barrett-Joyner-Halenda analysis is conducted on membrane samples to determine pore characteristics. Once the microstructure is characterized for each manufacturing process for both pristine and resin saturated samples, material properties of the membrane and nanocomposite structures are explored and compared on a manufacturing basis as well as a microstructural basis. Membranes samples are interleaved in the overlap of carbon fiber polymer matrix composite tubes, which are subjected to fracture testing. The effects of carbon nanotube membrane manufacturing technology on the fracture properties of nanocomposite structures with tubular geometries are explored. In parallel, the influences of manufacturing technology on the electromechanical properties of the membrane that effect a piezoresistive response are investigated for both pristine and resin saturated membranes manufactured using both methods. The result of this study is a better understanding of the relationships between manufacturing technology and the effected microstructure, and the resulting influences on material properties for both CNT membranes and derivative nanocomposite structures. Developing an understanding of these multiscale relationships leads to an increased capacity in designing manufacturing processes specific to optimizing the expression of desired characteristics for any given application.
ContributorsWoodward, John Michael (Author) / Chattopadhyay, Aditi (Thesis director) / Yekani Fard, Masoud (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Epoxy resins and composite materials are well characterized in their mechanical properties. However these properties change as the materials age under different conditions, as their microstructure undergoes changes from the absorption or desorption of water. Many of these microstructural changes occur at the interfacial region between where the matrix of the composite meets the reinforcement fiber, but still result in significant effects in the material properties. These effects have been studied and characterized under a variety of conditions by artificially aging samples. The artificial aging process focuses on exposing samples to environmental conditions such as high temperature, UV light, and humidity. While conditions like this are important to study, in real world applications the materials will not be simply resting in a laboratory created environment. In most circumstances, they are subjected to some kind of stress or impact. This report will focus on designing an experiment to analyze aged samples under tensile loading and creating a fixture that will sustain loading while the samples are aged. . The conditions that will be tested are control conditions at standard temperature and humidity in the laboratory, submerged, thermal heating, submerged and heated, and hygrothermal.
ContributorsNothern, Bradley James (Author) / Yekani Fard, Masoud (Thesis director) / Chattopadhyay, Aditi (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Shape Memory Polymers (SMPs) are smart polyurethane thermoplastics that can recover their original shape after undergoing deformation. This shape recovery can be actuated by raising the SMP above its glass transition temperature, Tg. This report outlines a process for repeatedly recycling SMPs using 3D printing. Cubes are printed, broken down into pellets mechanically, and re-extruded into filament. This simulates a recycling iteration that the material would undergo in industry. The samples are recycled 0, 1, 3, and 5 times, then printed into rectangular and dog-bone shapes. These shapes are used to perform dynamic mechanical analysis (DMA) and 3-point bending for shape recovery testing. Samples will also be used for scanning electron microscopy (SEM) to characterize their microstructure.
ContributorsSweeney, Andrew Joseph (Author) / Yekani Fard, Masoud (Thesis director) / Chattopadhyay, Aditi (Committee member) / W.P. Carey School of Business (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Seamless carbon fiber reinforced polymer matrix (CFRP) composites are being investigated in many structural applications with the purpose of withstanding the extreme pressures and maintaining stiffness in mechanical systems. This report focuses on: fabrication of CFRP tubes and end caps, the production of a pressurization system to test standards set by Fiber Reinforced Composite (FRC) Pipe and Fittings for Underground Fire Protection Service [1], developing a library for different damage types for seamless composite pipes, and evaluating pre-existing flaws with flash thermography, carrying out hydrostatic testing, and performing nondestructive testing (NDT) to characterize damage induced on the pipes such as cracking, crazing, and fiber breakage. The tasks outlined will be used to develop design guidelines for different combinations of loading systems.
ContributorsFoster, Collin William (Author) / Yekani Fard, Masoud (Thesis director) / Chattopadhyay, Aditi (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
Filament used in 3D printers can vary by size, color, and material. Most commonly thermoplastics are used for rapid prototyping by industry. Recycled filament has the potential to reduce cost and provide a more sustainable and energy efficient approach to 3D printing. This can be a viable option if recycled parts show comparable mechanical characteristics to non-recycled material. This report focuses on the development of a methodology to efficiently characterize recycled filament for application in industry. A crush sample in the shape of a hollow cube and a dog-bone shaped specimen will be created using a filament extruder and 3D printer. The crush sample will be broken and extruded to produce a recycled filament. The crush sample will undergo a varying number of recycles (i.e. breakings) per sample group to simulate mechanical degradation; 0, 1, 2, and 5 recycling loops. The samples will undergo micro mechanical (microscopy analysis) and macro mechanical (tensile) characterization.
ContributorsPalermo, Marissa Nicole (Author) / Chattopadhyay, Aditi (Thesis director) / Yekani Fard, Masoud (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Three dimensional printing is a growing field and an excellent medium for rapid prototyping. Its expansion has accelerated over recent years due to the increased affordability of the technology. It is now at the point where the startup cost to get into the field is down to the hobbyist price point. This means that there is an extremely high demand for affordable printing media. Current media such as ABS and PLA is extremely easy to form, but expensive and petroleum intensive to create. A recycling system that could work with a large variety of waste products could change the way that the maker community recycles. This Honors Thesis, or "Creative Project" will be centered on the product launch of small business 3DCycler. Although this launch will require pulling information and skills from various branches of both Business and Science, the scope of this project will be limited to specifically the market entrance of our small business/ product. Within this blanket goal, the project aims to define our target market/ its niche(s), develop proper IP/ lockout strategies, define future manufacturing strategies, and to fully define our beta product. The research was empirical in nature. Through data gathering techniques (e.g., consultations, interviews, survey), exploration was performed. Through these techniques the company 3DCycler took several calculated pivots in order to prepare the company for a strategic product launch and eventual acquisition.
ContributorsFarber-Schaefer, Blaine (Author) / Cho, Steve (Thesis director) / Goodman, Tom (Committee member) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This paper presents the methods used to fabricate carbon fiber tubes with different geometries that impact their critical failure modes. Two types of carbon fiber were used in the manufacturing process: seamless sleeve carbon fiber and stitched bonded sheet carbon fiber (PRI 2000-1-C). A manufacturing process for the tubes was developed for both geometries. Different epoxy systems were used for each fiber type. After curing, the surfaces of the tubes were inspected using flash thermography to characterize surface defects. The tube samples were placed in a three-point bending setup with an induced crack. The crack propagation was documented using a digital image correlation system. The process for finding the shape factors and energy release rate are presented. The fracture behavior of the tubes is compared to the data from the compact tension samples to develop damage tolerant design guidelines for tube type structures. Plate samples were prepared to compare the capacity to the demand of the circular hollow section samples. With the results of this study, design guidelines for damage tolerant structures are developed, which can be applied to many industries such as aviation, alternative energy production, and construction. This is crucial to the longevity and safety of structures and systems that are used daily in society.
ContributorsPadilla, Michael David (Author) / Chattopadhyay, Aditi (Thesis director) / Yekani Fard, Masoud (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This paper presents the methods and materials used to investigate the fatigue fracture properties of i) seamless twill weave carbon fiber and ii) stitch bonded biaxial carbon fiber polymer matrix composite. Additionally, the effect of notch tip placement relative to longitudinal fiber toes is investigated. The process for observing and characterizing fatigue crack damage propagation is presented. The fatigue fracture behavior is compared with data acquired from compact tension samples subjected to static tension tests in order to develop damage tolerant design guidelines for tube structures under fatigue loading.
ContributorsOramas, Mateo Alexis (Author) / Chattopadhyay, Aditi (Thesis director) / Yekani Fard, Masoud (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The purpose of this paper is to establish the rules governing current combat robotics and showcase an idea on how to create a more powerful robot. The robot would use its weapon to spin the rest of its body while having the weapon's gyro forces lift the entire robot and move it a set distance while spinning. Performing both of these actions simultaneously would create a more powerful robot through the use of a more destructive weapon system. Many initial tests were conducted to verify that the electronics and code worked and that the wheels could withstand the significant gyro forces when spinning. Multiple prototype chassis were designed and optimized to better handle the shape and the electronics went through several revisions so that they could be packaged in a cleaner and more space efficient way. A final prototype was designed with the knowledge from the initial tests which was then manufactured and tested to verify that the weapon could rotate the entire robot.
ContributorsWelsh, Kyle (Author) / Andersen, Erik (Thesis director) / Yekani Fard, Masoud (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / School for Engineering of Matter,Transport & Enrgy (Contributor)
Created2024-05