Tensile Testing Of 3d Printed Tpu Samples For Pediatric Biomaterial Applications,
2022
Embry-Riddle Aeronautical University
Tensile Testing Of 3d Printed Tpu Samples For Pediatric Biomaterial Applications, Sheridan C. Perry, Rodriguez M. Rafael, Victor Huayamave, Bryan M. Gonzalez, Kim Dae-Won, Zachary R. Nadeau
PanaSoMM
Additive Manufacturing (AM) has, in recent years, become one of the most widespread and preferred prototyping methods. The most popular additive manufacturing method is Fused Deposition Modeling. FDM’s popularity is primarily attributed to its 3 major strengths of rapid prototyping, variability in material choice, and subject specific nature. The medical industry is one of the larger industries that has benefited from 3D printing especially in the terms of medical trainers. Unfortunately, most medical trainers that are developed (either being 3d printed or through traditional manufacturing processes) are poor substitutes for the human body. This can be attributed to either a …
Mechanical And Durability Properties Of Geopolymer Concrete – A Review,
2022
Engineer, Department of Civil & Environmental Engineering, Faculty of Engineering, Beirut Arab University
Mechanical And Durability Properties Of Geopolymer Concrete – A Review, Lelian Elkhatib, Fadi Al Aridi, Adel Elkordi, Jamal Khatib
BAU Journal - Science and Technology
Owing to the ongoing increase in human population, there is a need for more construction projects including residential buildings and other amenities. Concrete is by far the dominant material used in construction and cement is a main ingredient. Cement manufacture is an energy intensive process and emit large amounts of carbon dioxide into the atmosphere. A reduction in the amount of cement used in construction is greatly beneficial. The use of geopolymer or alkali activated materials can serve this purpose as it attempts to totally replace cement in concrete. Geopolymers are materials that consist mainly of silica and alumina materials …
Computational Methods To Simulate Molten Salt Thermophysical Properties,
2022
Brigham Young University - Provo
Computational Methods To Simulate Molten Salt Thermophysical Properties, Talmage Porter, Michael M. Vaka, Parker Steenblik, Dennis Della Corte
Faculty Publications
Molten salts are important thermal conductors used in molten salt reactors and solar applications. To use molten salts safely, accurate knowledge of their thermophysical properties is necessary. However, it is experimentally challenging to measure these properties and a comprehensive evaluation of the full chemical space is unfeasible. Computational methods provide an alternative route to access these properties. Here, we summarize the developments in methods over the last 70 years and cluster them into three relevant eras. We review the main advances and limitations of each era and conclude with an optimistic perspective for the next decade, which will likely be …
Evaluating The Effects Of Granulated Rubber And Glass Fibers In Polymer Concrete As A Structural Material For Wafer Grinding Machines,
2022
California Polytechnic State University, San Luis Obispo
Evaluating The Effects Of Granulated Rubber And Glass Fibers In Polymer Concrete As A Structural Material For Wafer Grinding Machines, Kevin Gabriel Kuehn, Philip Randall Streeter
Materials Engineering
Polymer concrete is a composite material used to replace cast iron and steel in wafer grinding machines for vibration damping. During the grinding and lapping processes of manufacturing silicon wafers, excessive vibrations may cause subsurface damage which requires additional polishing and reduces yield. Nine compositions containing various levels of granulated rubber and glass fibers were manufactured. CRM WRF-10 granulated rubber was examined at 0%, 5%, and 10% and Corning Cem-Fil glass fibers were added at 0%, 0.5%, and 1% by weight. Smooth-On EpoxAcast 690 epoxy resin was held constant at 16% for each composition. Crushed granite aggregate from Martin Marietta, …
Effects Of Release Materials And Temperature Ramp Rates On The Surface Finish Of Carbon-Fiber Composite Components,
2022
California Polytechnic State University, San Luis Obispo
Effects Of Release Materials And Temperature Ramp Rates On The Surface Finish Of Carbon-Fiber Composite Components, Sudeep Louis, Thucmy Dang, Ethan Schlocker
Materials Engineering
Toray Advanced Composites is interested in improving their carbon fiber reinforced polymers (CFRP) manufacturing process by enhancing their control on the amount of surface roughness for varied customer preference. Surface roughness of CFRP is important in post-production processes including coating, priming, and painting. This project seeks to determine the effects of three release materials and two temperature ramp rates on the surface finish of CFRP. The release materials used were Tooltech, FEP, and Frekote 770-NC. The two initial temperature ramp rates were 1°F/min and 2°F/min. Surface roughness was measured using a profilometer and analyzed using Ra values. Ra is an …
Analysis Of Novel Corrosion Resistant Maraging Steels For Use In Additive Manufacturing,
2022
California Polytechnic State University, San Luis Obispo
Analysis Of Novel Corrosion Resistant Maraging Steels For Use In Additive Manufacturing, Bradley Michael Samuel, James Knowlton Smith
Materials Engineering
Stainless maraging steel has been proven to be an industry standard material for plastic injection molds. Its high hardness and corrosion resistance extend the lifetime of the tool. This alloy system is also well-suited to additive manufacturing, which can be utilized to form internal cooling channels, further increasing tool life. Using Rapid Alloy Development (RAD) Oerilkon METCO is developing a new composition of stainless maraging tool steel that has high hardness/strength, is corrosion resistant, and has additive-capable melting and solidification properties. This study tests the hardness and corrosion resistance of the new RAD alloys against the current market competitor Corrax …
Non-Destructive Material Analysis Of Metals And Composites Via Thermography,
2022
California Polytechnic State University, San Luis Obispo
Non-Destructive Material Analysis Of Metals And Composites Via Thermography, Jonathan R. Doubt, James L. Chapman
Materials Engineering
The Naval Surface Warfare Center, Port Hueneme Division, is interested in the development of non-destructive damage assessment of shipboard materials via drones at distance. Long Pulsed Thermography (LPT), a method of non-destructive evaluation, was investigated as a possible method for detecting damage in metals (5005h24 Al alloy and 1008 carbon steel) and composites (aramid fiber honeycomb sandwich structure) at distances from 0.5 m to 3.0 m. LPT was conducted using two 1000 W can lights to heat the samples, and a FLIR E8-XT thermal camera. The images were then analyzed using ImageJ software to determine if damage could be detected …
Investigation Of The Effects Of Cladding Layers On Longitudinal And Transverse Mechanical Properties In Composite Laminates,
2022
California Polytechnic State University, San Luis Obispo
Investigation Of The Effects Of Cladding Layers On Longitudinal And Transverse Mechanical Properties In Composite Laminates, Rachel Potratz, Tiffany Foo, Joseph Kamlet
Materials Engineering
The addition of cladding layers to composite laminates is used in industry to improve bond adhesion and the ease of manufacturing. However, there is no public data on the effects of cladding layers on the mechanical properties of composite components. To directly observe how cladding layers affect mechanical properties, four laminates with zero, one, two, and three cladding layers of twill fabric were added symmetrically to a biased core. The mechanical testing performed was tensile, short beam strength, and compression testing in the longitudinal and transverse directions. The measured strengths were related to the longitudinal properties of the core, and …
A Modular Synthesis Of Processable And Thermally Stable Semi-Fluorinated Aryl Ether Polymers Via Step-Growth Polymerization Of Fluoroalkenes,
2022
Mississippi State University
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 …
Challenges And Signal Processing Of High Strain Rate Mechanical Testing,
2022
Mississippi State University
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 …
Biodegradable Active Bio-Nanocomposite Film For The Enhanced Shelf Life Of Tomatoes,
2022
Technological University Dublin
Biodegradable Active Bio-Nanocomposite Film For The Enhanced Shelf Life Of Tomatoes, Kalpani Y. Perera, Shubham Sharma, Brendan Duffy, Amit K. Jaiswal, Swarna Jaiswal
Articles
The increased environmental pollution has led to finding sustainable solutions for non-renewable plastic-based food packaging materials. Thus, the use of biomaterial-based packaging material has become an immense trend. This work aims at developing an antimicrobial biodegradable chitosan-alginate bio-nano composite film with TiO2 nanoparticle (NPs) for food packaging applications. The film was developed by a solution casting method. The chemical, mechanical, thermal, barrier, antimicrobial, and biodegradable properties of the packaging films were evaluated. Packaging studies were performed for 15 days for cherry tomatoes. The designed packaging material had enhanced the mechanical properties with a significantly (p < 0.05) higher tensile strength of 15.76 folds and 2 fold higher elongation at break. The UV barrier properties increased by 88.6%, while the film transparency decreased by 87.23%. Molecular interaction of N-H covalent bonds was observed between alginate and chitosan together with TiO2 NPs. The developed bio-nano composite film showed antimicrobial activity against foodborne pathogens E. coli, S. aureus, S. typhi, and L. monocytogene with a log reduction of 7.08, 7.28, 6.04 & 6.02 log CFU/ml respectively at 24 hours incubation period. The film was completely biodegraded and a weight loss of 89.06% was observed in bio-nanocomposite film during the 3 months. Shelf-life estimation of cherry tomato using developed packaging films showed an increase in the shelf-life up to 8 days with stable pH, total soluble solids, and weight with no bacterial growth when packaged with prepared film. Owing to their improved mechanical, UV barrier, antibacterial, and biodegradability, the prepared active bio-nano composite packaging films could be considered a potential candidate for fruit packaging.
Designing & Building A Microwave Plasma Reactor For Graphene Synthesis,
2022
Chapman University
Designing & Building A Microwave Plasma Reactor For Graphene Synthesis, Aviv Zohman, Jerry Larue
Student Scholar Symposium Abstracts and Posters
Graphene’s remarkable electrical, optical, and chemical properties make it a promising successor to indium tin oxide for applications in flexible, transparent electronics. However, efforts to manufacture graphene have been hindered by inefficient synthesis and transfer methods. Chemical vapor deposition (CVD) is commonly used to produce graphene. CVD starts with a blank surface onto which a chemical vapor is deposited to create a single graphene layer. CVD requires extreme temperatures, so only substrates with high melting points are applicable, like metals. This excludes insulative substrates such as polymers which are essential to transparent and flexible devices. Therefore, a subsequent process transfers …
Characterization Of Hydrogen Embrittlement Sensitivity In High Hardness Steels,
2022
Mississippi State University
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 …
Enhancing Stability Of High-Nickel Cathodes For Lithium-Ion Batteries Through Additive Manufacturing Of Cathode Structure,
2022
University of Arkansas, Fayetteville
Enhancing Stability Of High-Nickel Cathodes For Lithium-Ion Batteries Through Additive Manufacturing Of Cathode Structure, Matthew Sullivan
Mechanical Engineering Undergraduate Honors Theses
Lithium-ion batteries (LIBs) are currently the best method to store electrical energy for use in portable electronics and electronic vehicles. New cathode materials for LIBs are consistently studied and researched, but few are as promising and attainable as nickel-rich transition metal oxides such as LiNi1-x-yMnxCoyO2 (NMC). NMC materials exist with many different mass ratios, but higher nickel content materials provide higher energy density. With this increase in capacity comes a sacrifice with cyclability, as high-nickel NMC variants are prone to structure collapse, transition metal dissolution, and cracks due to volume change. In this report, mechanical modification of the electrode by …
Preparation, Cure, And Characterization Of Cyanate Ester-Epoxy Blends,
2022
University of Dayton
Preparation, Cure, And Characterization Of Cyanate Ester-Epoxy Blends, Donald A. Klosterman
Chemical and Materials Engineering Faculty Publications
Cyanate ester resins are often blended with lower cost epoxy monomers in order to modify the cost, toughness, and processing characteristics. There are also several choices of catalysts that can be used to improve processing, namely by reducing the cure temperature. This study was undertaken to illustrate how a designed experiment approach can be used to systematically investigate a wide range of material combinations and illuminate the basic cure behavior of some simple cyanate ester – epoxy blend combinations. Two commercial cyanate ester resin products were obtained. Each was blended with a bisphenol F based epoxy resin at two different …
Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication,
2022
University of New Orleans
Additive Manufacturing Of Variable Contrast Computed Tomography Anatomical Phantoms Using A Single Feedstock In Fused Filament Fabrication, Cory J. Darling
LSU New Orleans Theses and Dissertations
Anatomical phantoms used in biomedical education and training benefit greatly from Fused filament fabrication’s (FFF) ability to rapidly produce complex and unique models. Current materials and methods used in FFF have limited ability to accurately produce phantoms that can mimic the radiological properties of multiple biological tissues. This research demonstrates that the CT contrast of FFF produced models can be modified by varying the concentration of bismuth oxide in acrylonitrile butadiene styrene (ABS) filaments and a tunable CT contrast that mimics the CT contrast ranging from fatty tissue to cortical bone using a single composite filament without introducing artificial image …
Sustainable Composites From Agricultural And Petroleum Waste,
2022
Clemson University
Sustainable Composites From Agricultural And Petroleum Waste, Menisha S. Karunarathna
All Dissertations
Green gas emission has been a pervasive and persistent subject of debate for a prolonged period. The soaring number of industries and vehicle fuel emissions presage a concomitant rise in global CO2 emissions. Global cement production is responsible for 8% of the total CO2 release, yet, the production continues due to the surging demand. Hence, there is an ongoing quest to find alternatives for cement and building materials produced with zero to lower CO2 emissions. The work presented in this dissertation focuses on finding recyclable, zero CO2 gas-producing high sulfur biocomposites materials, which can compete with …
Detection And Identification Of Disturbances By Spectral Analysis Of Structure-Borne Noise During The Production Of A Sealing Seam,
2022
Robert Bosch GmbH, Stuttgart, Germany and Dresden University of Technology, Chair of Processing Machines/Processing Technology, Dresden, Germany
Detection And Identification Of Disturbances By Spectral Analysis Of Structure-Borne Noise During The Production Of A Sealing Seam, Felix Kruppa, Lars Meisenbach, Berend Oberdorfer Dr.-Ing., Bernd Wilke Prof. Dr.-Ing.
Journal of Applied Packaging Research
When sealing, disturbances or errors can occur that impair the quality of the sealing seam and, in the worst case, lead to leaks. It is therefore important to identify and eliminate defective packages during production and to minimize the elimination by readjusting machine parameters. The aim of this article is the clear identification of seam quality problems on a vertical forming, filling and sealing machine SVE2520 by evaluating process parameters during the manufacturing process. For this purpose, the structure-borne noise is measured for each seal in order to identify not-usual curves. These not-usual curves are related to different disturbances or …
Optimizing The Self-Healing Efficiency Of Hydrogel Encapsulated Bacteria In Concrete,
2022
Louisiana State University
Optimizing The Self-Healing Efficiency Of Hydrogel Encapsulated Bacteria In Concrete, Ricardo Hungria
LSU Master's Theses
Calcium carbonate precipitation through microbial means is a promising pathway for concrete self-healing technologies, mainly for its microcrack sealing attributes. The main goal of this project was to study and optimize the crack healing efficiency of hydrogel encapsulated bacteria in concrete. To achieve this purpose, Bacillus pseudiformus was implemented as the bacteria strain at a concentration of 108 cells/ml. This bacterium strain along with yeast extract was combined along with three different mineral precursors corresponding to magnesium acetate, calcium lactate, and sodium lactate. All these three precursors were evaluated at two concentrations (67.76 mM/l and 75 mM/l). For each …
Detection Of Trace Heavy Metals In Water: Development Of Electrochemical Sensors,
2022
Kennesaw State University
Detection Of Trace Heavy Metals In Water: Development Of Electrochemical Sensors, Quang Lam, Joel Mututeke
Symposium of Student Scholars
The presence of heavy metals in our ecosystem poses significant ecological and physiological consequences. As a result, numerous techniques are developed for the detection of contaminants in aqueous solutions. However, early and trace detection of such contaminants still remains a challenge. Amongst many techniques, electrochemistry driven sensors have shown promise due to their possibility of miniaturization and low-cost. Our research investigates the use of electrically conducting polymer and atomically thin carbon materials as electrodes towards the development of electrochemical sensor. Nanocomposite electrode films have been synthesized and fabricated using in-situ polymerization technique and the relationship between number of cycles of …
