The Impact of Implementing an Invariant-Based Theory of Composites on the Automotive Industry

Description
A novel approach, the Invariant Based Theory of Composites and the "Trace" method it proposes, has the potential to reduce aerospace composite development times and costs by over 30% thus reinvigorating the development process and encouraging composite technology growth. The

A novel approach, the Invariant Based Theory of Composites and the "Trace" method it proposes, has the potential to reduce aerospace composite development times and costs by over 30% thus reinvigorating the development process and encouraging composite technology growth. The "trace" method takes advantage of inherent stiffness properties of laminates, specifically carbon fiber, to make predictions of material properties used to derive design allowables. The advantages of the "trace" theory may not necessarily be specific to the aerospace industry, however many automotive manufacturers are facing environmental, social and political pressure to increase the gas mileage in their vehicles and reduce their carbon footprint. Therefore, the use of lighter materials, such as carbon fiber composites, to replace heavier metals in cars is inevitable yet as of now few auto manufacturers implement composites in their cars. The high material, testing and development costs, much like the aerospace industry, have been prohibitive to widespread use of these materials but progress is being made in overcoming those challenges. The "trace" method, while initially intended for quasi-isotropic, aerospace grade carbon-fiber laminates, still yields reasonable, and correctable, results for types of laminates as well such as with woven fabrics and thermoplastic matrices, much of which are being used in these early stages of automotive composite development. Despite the varying use of materials, the "trace" method could potentially boost automotive composites in a similar way to the aerospace industry by reducing testing time and costs and perhaps even playing a role in establishing emerging simulations of these materials.
Date Created
2016-05
Agent

From Pedometers to Giving Sight to the Blind: Market Research for Wearable Electronics

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Description
How can we change what it means to be a human? Products can be used that will allow for near-instantaneous communication with one’s friends and family wherever they are: and the newest devices do not have to be even carried

How can we change what it means to be a human? Products can be used that will allow for near-instantaneous communication with one’s friends and family wherever they are: and the newest devices do not have to be even carried around, as they can be worn instead. Wearable electronics are quickly becoming very popular, with 232.0 million wearable devices sold in 2015. This report provides an overview of current and developing wearable devices, investigates the characteristics of the average buyer for these different types of devices. Finally, marketing strategies are suggested. This work was completed in conjunction with a capstone project with Intel, where three objectives were achieved: First, a universal strain tester that could strain samples cyclically in a manner similar to the body was designed. This equipment was especially designed to be flexible in the testing conditions it could be exposed to, so samples could be tested at elevated temperatures or even underwater. Next, dogbone shaped samples for the testing of Young’s Modulus and elongation to failure were produced, and the cut quality of laser, water-jet, and die-cutting was compared in order to select the most defect-free method for reliable testing. Polydimethylsiloxane (PDMS) is a fantastic candidate material for wearable electronics, however there is some discrepancies in the literature—such as from Eleni et. al—about the impact of ultraviolet radiation on the mechanical properties. By conducting accelerated aging tests simulating up to five years exposure to the sun, it was determined that ultraviolet-induced cross-linking of the polymer chains does occur, leading to severe embrittlement (strain to failure reduced from 3.27 to 0.06 in some cases, reduction to approximately 0.21 on average). As simulated tests of possible usage conditions required strains of at least 0.50-0.70, a variety of solutions were suggested to reduce this embrittlement. This project can lead to standardization of wearables electronics testing methods for more reliable predictions about the device behavior, whether that device is a simple pedometer or something that allows the visually impaired to “see”, such as Toyota’s Blaid.
Date Created
2016-05
Agent

Aptamer-functionalized Hydrogel for the Capture and Release of CCRF-CEM Leukemia Cancer Cells

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Description
The main objective of this project is to create a hydrogel based material system to capture and release CCRF-CEM Leukemia cancer cells via chemo-mechanical modulation. This system is composed of an aptamer-functionalized hydrogel thin film at the bottom of a

The main objective of this project is to create a hydrogel based material system to capture and release CCRF-CEM Leukemia cancer cells via chemo-mechanical modulation. This system is composed of an aptamer-functionalized hydrogel thin film at the bottom of a microfluidic channel, which changes its film thickness as the temperature of the fluid in the system changes. The functionalized hydrogel film has been created as the primary steps to creating the microfluidic device that could capture and release leukemia cells by turning the temperature of the fluid and length of exposure. Circulating tumor cells have recently become a highly studied area since they have become associated with the likelihood of patient survival. Further, circulating tumor cells can be used to determine changes in the genome of the cancer leading to targeted treatment. First, the aptamers were attached onto the hydrogel through an EDC/NHS reaction. The aptamers were verified to be attached onto the hydrogel through FTIR spectroscopy. The cell capture experiments were completed by exposing the hydrogel to a solution of leukemia cells for 10 minutes at room temperature. The cell release experiments were completed by exposing the hydrogel to a 40°C solution. Several capture and release experiments were completed to measure how many cells could be captured, how quickly, and how many cells captured were released. The aptamers were chemically attached to the hydrogel. 300 cells per square millimeter could be captured at a time in a 10 minute time period and released in a 5 minute period. Of the cells captured, 96% of them were alive once caught. 99% of cells caught were released once exposed to elevated temperature. The project opens the possibility to quickly and efficiently capture and release tumor cells using only changes in temperature. Further, most of the cells that were captured were alive and nearly all of those were released leading to high survival and capture efficiency.
Date Created
2016-12
Agent

The Benefits and Application of Statistical Process Control in a Manufacturing Environment

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Description
Statistical process control (SPC) is an important quality application that is used throughout industry and is composed of control charts. Most often, it is applied in the final stages of product manufacturing. However it would be beneficial to apply SPC

Statistical process control (SPC) is an important quality application that is used throughout industry and is composed of control charts. Most often, it is applied in the final stages of product manufacturing. However it would be beneficial to apply SPC throughout all stages of the manufacturing process such as the beginning stages. This report explores the fundamentals of SPC, applicable programs, important aspects of implementation, and specific examples of where SPC was beneficial. Important programs for SPC are general statistical software such as JMP and Minitab, and some programs are made specifically for SPC such as SPACE: statistical process and control environment. Advanced programs like SPACE are beneficial because they can easily assist with creating control charts and setting up rules, alarms and notifications, and reaction mechanisms. After the charts are set up it is important to apply rules to the charts to see when a system is running off target which indicates the need to troubleshoot and investigate. This makes the notification part an integral aspect as well because attention and awareness must be brought to out of control situations. The next important aspect is ensuring there is a reaction mechanism or plan on what to do in the event of an out of control situation and what to do to get the system running back on target. Setting up an SPC system takes time and practice and requires a lot of collaboration with experts who know more about the system or the quality side. Some of the more difficult parts of implementation is getting everyone on board and creating trainings and getting the appropriate personnel trained.
Date Created
2016-12
Agent

Dissolvable Metal Supports - Simplifying Metals Printing

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Description
Additive Manufacturing and 3D printing are becoming important technologies in the manufacturing sector. The benefits of this technology include complex part geometry, short lead-times, low waste, and simple user interface. However, the technology does not come without its drawbacks: mainly

Additive Manufacturing and 3D printing are becoming important technologies in the manufacturing sector. The benefits of this technology include complex part geometry, short lead-times, low waste, and simple user interface. However, the technology does not come without its drawbacks: mainly the removal of support structures from the component. Traditional techniques that involve sawing and cutting can be expensive and take a long time, increasing the overall price of 3D printed metal components. This paper discusses two approaches taken for dissolvable support structures in 3D printed stainless steel (17-4 PH). For the first time in powder bed fusion components, with the help of Christopher Lefky and Dr. Owen Hildreth, dissolvable support capabilities are achieved in metal prints. The first approach, direct dissolution, involves direct corrosion of the entire part, leading to support removal. This approach is not self-terminating, and leads to changes in final component geometry. The second approach involves a post-build sensitization step, which physically alters the microstructure and chemical stability of the first 100-200 microns of the metal. The component is then etched at an electric potential that will readily corrode this sensitized surface, but not the underlying base metal. An electrolytic solution of HNO3/KCl/HCl paired with an anodic bias was used for the direct dissolution approach, resulting in a loss of about 120 microns of material from the components surface. For the self-limiting approach, surface sensitization was achieve through a post build annealing step (800 C for 6 hours, air cooled) with exposure to a sodium hexacynoferrate slurry. When the slurry decomposes in the furnace, carbon atoms diffuse into the surface and precipitate a chromium-carbide, which reduces the chemical stability of the stainless steel. Etching is demonstrated in an anodic bias of HNO3/KCl. To determine proper etching potentials, open circuit potential and cyclic voltammetry experiments were run to create Potentiodynamic Polarization Curves. Further testing of the self-terminating approach was performed on a 316 stainless steel interlocking ring structure with a complex geometry. In this case, 32.5 hours of etching at anodic potentials replaced days of mechanical sawing and cutting.
Date Created
2016-12
Agent

LTA Zeolite Monolayers via the Langmuir-Blodgett Technique

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Description
Zeolite thin films and membranes are currently a promising technology for pervaporation, gas separation and water purification. The main drawback with these technologies is that the synthesis is not consistent leading to varied and unreproducible results. The Langmuir-Blodgett technique is

Zeolite thin films and membranes are currently a promising technology for pervaporation, gas separation and water purification. The main drawback with these technologies is that the synthesis is not consistent leading to varied and unreproducible results. The Langmuir-Blodgett technique is a robust method for transferring monolayers of molecules or crystals to a solid substrate. By measuring the surface pressure and controlling the area, reliable results can be achieved by transferring monolayers to different solid substrates. It has been shown previously that various types of zeolites can be functionalized and dispersed on the top of water. This is done by using an alcohol to form a hydrophobic coating on the surface of zeolite. The Langmuir-Blodgett can be used to create thin, compact films of zeolites for synthesizing and growing zeolite films. For the first reported time, cubic LTA Zeolites monolayers have been assembled with the Langmuir-Blodgett technique with multiple solvents and different sizes of zeolites. These films were characterized with Scanning Electron Microscopy and Pressure-Area Isotherms generated from the Langmuir-Blodgett. It was found that linoleic acid is a required addition to the zeolite dispersions to protect the mechanical stability during agitation. Without this addition, the LTA zeolites are broken apart and lose their characteristic cubic structure. This effect is discussed and a theory is presented that the interparticle interactions of the long alkane chain of the linoleic acid help reduce the shear stress on the individual zeolite particles, thus preventing them from being broken. The effect of size of the zeolites on the monolayer formation was also discussed. There seemed to be little correlation between the monolayer quality and formation as size was changed. However, to optimize the process, different concentrations and target pressures are needed. Lastly, the effect of the solvent was explored and it was found that there is a different between monolayer formations for different solvents likely due to differing interparticle interactions. Overall, LTA zeolites were successfully fabricated and the important factors to consider are the zeolite size, the solvent, and the amount of surfactant stabilizer added.
Date Created
2016-12
Agent

Densification of Li7La3Zr2O12 Electrospun Nanowires Through Processing Control of Intermediate La2Zr2O7 Phase (Electrospinning Synthesis of Electrolytes for Solid-state Lithium-ion Batteries)

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Description
Solid-state lithium-ion batteries are a major area of research due to their increased safety characteristics over conventional liquid electrolyte batteries. Lithium lanthanum zirconate (LLZO) is a promising garnet-type ceramic for use as a solid-state electrolyte due to its high ionic

Solid-state lithium-ion batteries are a major area of research due to their increased safety characteristics over conventional liquid electrolyte batteries. Lithium lanthanum zirconate (LLZO) is a promising garnet-type ceramic for use as a solid-state electrolyte due to its high ionic conductivity. The material exists in two dierent phases, one that is cubic in structure and one that is tetragonal. One potential synthesis method that results in LLZO in the more useful, cubic phase, is electrospinning, where a mat of nanowires is spun and then calcined into LLZO. A phase containing lanthanum zirconate (LZO) and amorphous lithium occursas an intermediate during the calcination process. LZO has been shown to be a sintering aid for LLZO, allowing for lower sintering temperatures. Here it is shown the eects of internal LZO on the sintered pellets. This is done by varying the 700C calcination time to transform diering amounts of LZO and LLZO in electrospun nanowires, and then using the same sintering parameters for each sample. X-ray diraction was used to get structural and compositional analysis of both the calcined powders and sintered pellets. Pellets formed from wires calcined at 1 hour or longer contained only LLZO even if the calcined powder had only undergone the rst phase transformation. The relative density of the pellet with no initial LLZO of 61.0% was higher than that of the pellet with no LZO, which had a relative density of 57.7%. This allows for the same, or slightly higher, quality material to be synthesized with a shorter amount of processing time.
Date Created
2017-05
Agent

Membrane modification for sensing urine biomarker levels

Description
Acute Kidney Injury (AKI) may be detected through biomarkers in urine. This research is being done to develop a membrane for use in separating urine biomarkers to monitor their level. A hydrophobic membrane was treated to improve separation of the

Acute Kidney Injury (AKI) may be detected through biomarkers in urine. This research is being done to develop a membrane for use in separating urine biomarkers to monitor their level. A hydrophobic membrane was treated to improve separation of the desired biomarker for colorimetric sensing. This method was tested with model solutions containing the biomarker. Future work will extend to testing with real urine.
Date Created
2017-05
Agent

Effect of Winglet Morphology on Variable Range Commercial Aircraft

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Description
Winglets and wingtip structures have been prominent in commercial aircraft design in the past few decades. These designs are known to reduce the induced drag on an aircraft wing, thus increasing its overall fuel efficiency. Several different winglet designs exist,

Winglets and wingtip structures have been prominent in commercial aircraft design in the past few decades. These designs are known to reduce the induced drag on an aircraft wing, thus increasing its overall fuel efficiency. Several different winglet designs exist, and little reason is offered as to why different winglet designs are used in practice on different aircraft, especially those of variable range. This research tests existing winglets (no winglet, raked winglet, flat plate winglet, blended winglet, and wingtip fence) on a span-constrained wing planform design both computationally and in the wind tunnel. While computational tests using a vortex lattice code indicate that the wingtip fence minimizes induced drag and maximizes lift to drag ratio in most cases, wind tunnel tests show that at different lift coefficients and angles of attack, the raked winglet and blended winglet optimize the aerodynamic efficiency at incompressible flow velocities. Applying the wing aerodynamic data to existing variable range commercial aircraft, mission performance analysis is run on a Bombardier CRJ200, Airbus A320, and Airbus A340-300. By comparing flight lift coefficients in cruise for these aircraft to the lift coefficients at which winglets minimize drag in compressible flows, optimal winglet designs are chosen. It is found that the short range CRJ200 is best equipped with a flat plate or blended winglet, the medium range A320 can reduce drag with either a wingtip fence, raked winglet, or blended winglet, and the long range A340 performs best with a flat plate, blended, or raked winglet. Overall, despite the discrepancy in winglet selection depending on which experimental results are used, it is clear that addition of a winglet to a span-constrained wing is beneficial in that it reduces induced drag and therefore increases overall fuel efficiency.
Date Created
2017-05
Agent

Damage Detection and Quantification in Advanced Foam-core composites

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Description
Composite structures, particularly carbon-fiber reinforced polymers (CFRPs) have been subject to significant development in recent years. They have become increasingly reliable, durable, and versatile, finding a role in a wide variety of applications. When compared to conventional materials, CFRPs have

Composite structures, particularly carbon-fiber reinforced polymers (CFRPs) have been subject to significant development in recent years. They have become increasingly reliable, durable, and versatile, finding a role in a wide variety of applications. When compared to conventional materials, CFRPs have several advantages, including extremely high strength, high in-plane and flexural stiffness, and very low weight. However, the application of CFRPs and other fiber-matrix composites is complicated due to the manner in which damage propagates throughout the structure, and the associated difficulty in identifying and repairing such damages prior to structural failure. In this paper, a methods of detecting and localizing delaminations withint a complex foam-core composite structure using non-destructive evaluation (NDE) and structural health montoring (SHM) is investigated. The two NDE techniques utilized are flash thermography and low frequency ultrasonic C-Scan, which were used to confirm the location of seeded damages within the specimens and to quantify the size of the damages. Macro fiber composite sensors (MFCs) and piezoelectric sensors (PZTs) were used as actuators and sensors in pitch-catch and pulse-echo configurations in order to study mode conversions and wave reflections of the propagated Lamb waves when interacting with interply delaminations and foam-core separations. The final results indicated that the investigated NDE and SHM techniques are capable of detecting and quantifying damages within complex X-COR composites, with the SHM techniques having the potential to be used \textit{in situ} with a high degree of accuracy. It was also observed that the presence of the X-COR significantly alters the behavior of the wave when compared to a standard CFRP composite plate, making it necessary to account for any variations if wave-base techniques are to be used for damage detection and quantification. Lastly, a time-space model was created to model the wave interactions with damages located within X-COR complex sandwich composites.
Date Created
2017-05