Other Materials Science and Engineering Commons^™

Development Of Smart Wearable Sensory Systems On Flexible And Fabric Platforms For Health Monitoring Applications, Simin Masihi

Dissertations

Wearable sensing technology has recently received an increased attention in both research and commercialization phases and has moved from a vision of science fiction to reality with a wide variety of applications. This incredible growth can be attributed to several factors, such as affordability and ergonomics provided by advances in flexible electronics. The other factors that realized wearable sensing technology include a critical need for more accessible health care services experienced during the recent COVID pandemic, integration to the Internet of Things (IoT), and a growing consumer desire for health awareness. This dissertation presents the fulfillment of three main projects …

Creep Behavior Of A Ti-Based Multi-Principal Element Alloy, Benjamin Elbrecht

All Theses

Abstract

The understanding of microstructural damage mechanisms is the foundation of better understanding existing materials and future material development. There are significant challenges to measuring these damage mechanisms in-situ as continuous observation of the state of the microstructure is difficult or impossible for many experimental setups. This thesis presents a method for measuring grain boundary sliding (GBS) and local strain concentrations in-situ via a Heaviside function based algorithm. GBS is the shearing of two grains along their shared grain boundary and is a common damage mechanism in creep which presents as a discontinuity that can be measured with a Heaviside …

Rheological Properties And Structural Build-Up Of 3d Printed Magnesium Potassium Phosphate Cement, Hui Zhi Zhao

International Conference on Durability of Concrete Structures

This paper focuses on the rheological properties of 3D printed magnesium potassium phosphate cements (MKPCs) with different magnesium-to-phosphate (M/P) mass ratio, MgO fineness and supplementary cementitious materials (SCMs) types. The variable shear rate tests were used to monitor the extrudability. The highest slope of the evolution of storage modulus (G') and the maximum static yield stress (M_τs) value were used as an indication of the rigidification rate. The increased M/P mass ratio, MgO fineness and SCMs addition resulted in the promoted structural build-up of 3D printed MKPCs. The consistency between the evolution of G' and M_τs with …

Mechanical Properties And Microstructure Of High Strength Lc3 Pastes With Varying Limestone/Calcined Clay Ratios And Different Curing Conditions, Yemin Dong

International Conference on Durability of Concrete Structures

研究（抗施工蒸馏）石石和石榴石在淀粉胶系统（即0标准和低水印）下的水胶系统（即0标准和低水墨）X射线比、水量值水量-电子背基相关研究.61.25 .25.25.25.0.25.25.25.25.25.0.25.25.25.25.25.1.25.7.25.0.0.0.0.0.0.0.0.0.0.0.0.0.0.1.25.1.25.25.1.25.1.25.1.25.1.25.1.25.1 .25.1.25.1.25.1.25.1.25.1.25.0.0.0.0.0.0.0.00.0.0.1.25.1.25.1.25.1.25.1.25.0.0.0.00.0.0.0.0.0.0.0.0.0.0.0.0.0.00.0 .00.0.00.X射线比值、水量-电子显微镜相关研究测量值。早期的水泥水化程度小水的压合含煤量，降低了水泥石的。因此，需要采用合适的钙铝内容和体系以提高碳系统的性能。

Mechanical And Thermal Insulation Properties Of Clay-Based Lightweight Concrete, Chuang Shi, Chuanlin Hu

International Conference on Durability of Concrete Structures

建材生产和住宅采暖将消耗大量能源并排放大量CO_2。在混凝土制备中，使用陶土制备具有优异隔热性能的轻质混凝土，并使用煅烧粘土代替部分波特兰水泥，可以大大降低能耗。本研究采用页岩陶土和陶砂分别作为粗骨料和细骨料制备轻质混凝土。首先，确定最佳体积砂比。然后，使用煅烧粘土和石灰石的剂量从30%，50%到70%。研究了煅烧粘土和石灰石含量对混凝土微观结构、力学性能和隔热性能的影响。结果表明，最佳体积砂比为50%。当煅烧粘土和石灰石的用量为30%时，强度在所有年龄段最高，28 d时强度可达33.6 MPa，比对照组高12%。当更换水平不断增加时，所有年龄段的实力开始下降。所制备的粘土基轻质混凝土的导热系数低至0.144 W/mK，表现出优异的保温性能。本研究制备的轻质混凝土具有较高的强度和优异的保温性能，具有良好的应用前景。

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, 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 …

Damage In Non-Crimp Fabric Carbon Fiber Reinforced Epoxy Composites Under Various Mechanical Loading Conditions, Aaditya Pradeep Suratkar

Electronic Thesis and Dissertation Repository

Composite materials have emerged in the recent years as a frontrunning lightweight replacement for metals for structural applications in lightweight automobiles. However, the key adoption criteria for composites in lightweight vehicles is their crashworthiness, i.e., the amount of energy a structure made with composites would absorb in a crash event. The energy is absorbed in composites through various damage modes such as matrix cracks, delamination, fiber breakage, etc. Therefore, adoption of a certain composite material system requires thorough understanding of the initiation and propagation of damage until failure in that system under various mechanical loading conditions, which is also the …

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, 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 …

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 …

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 …

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, …

On The Effects Of Additive Manufacturing Process Parameters On The Performance Of Hastelloy-X: A Neutron Diffraction Experiment And Crystal Plasticity Finite Element Model, Ahmed Aburakhia

Electronic Thesis and Dissertation Repository

Additive manufacturing (AM) is increasingly becoming one of the favourable manufacturing techniques in various industries, such as transportation and energy. The reason for the extensive use of AM lies in the ability to use a wide range of process parameters for manufacturing engineering parts with complex geometries that cannot be effectively manufactured using traditional methods such as casting or forging. Understanding the role of process parameters is crucial for developing predictive models, as well as for manufacturing engineering components with the desired properties.

This research aims to characterize the influence of AM process parameters on the deformation mechanisms of Hastelloy-X, …

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, 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, 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, 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 …

Optimizing Aqueous Processing Of Nickel-Rich Cathode Material In Ultra-Thick Lithium-Ion Batteries, Alexander J. Kukay

Doctoral Dissertations

Lithium-ion batteries (LIBs) have been an instrumental technology since their commercialization in the 1990s. Although much progress has been made in terms of cost and efficiency of production, several challenges remain. Notably, as LIB technology continues to be applied to the transportation sector for electrified mobility in the form of electric vehicles, the question of production ethics and environmental sustainability becomes paramount. The aim of this dissertation is to address some of these concerns in the form of cathode processing techniques. This dissertation focuses on optimization of aqueous processing applied to cathode active materials. First, a study demonstrating the feasibility …

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 …