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

Materials Science and Engineering Commons™

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

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 3811 - 3840 of 16796

Full-Text Articles in Materials Science and Engineering

Recent Development Of Low Iridium Electrocatalysts Toward Efficient Water Oxidation, Jing Ni, Zhao-Ping Shi, Xian Wang, Yi-Bo Wang, Hong-Xiang Wu, Chang-Peng Liu, Jun-Jie Ge, Wei Xing Sep 2022

Recent Development Of Low Iridium Electrocatalysts Toward Efficient Water Oxidation, Jing Ni, Zhao-Ping Shi, Xian Wang, Yi-Bo Wang, Hong-Xiang Wu, Chang-Peng Liu, Jun-Jie Ge, Wei Xing

Journal of Electrochemistry

Developing high-performance and low-cost electrocatalysts for oxygen evolution reaction (OER) is the key to implementing polymer electrolyte membrane water electrolyzer (PEMWE) for hydrogen production. To date, iridium (Ir) is the state-of-the-art OER catalyst, but still suffers from the insufficient activity and scarce earth abundance, which results in high cost both in stack and electricity. Design low-Ir catalysts with enhanced activity and stability that can match the requirements of high current and long-term operation in PEMWE is thus highly desired, which necessitate a deep understanding of acidic OER mechanisms, unique insights of material design strategies, and reliable performance evaluation norm, especially …


A Co Porphyrin With Electron-Withdrawing And Hydrophilic Substituents For Improved Electrocatalytic Oxygen Reduction, Hong-Bo Guo, Ya-Ni Wang, Kai Guo, Hai-Tao Lei, Zuo-Zhong Liang, Xue-Peng Zhang, Rui Cao Sep 2022

A Co Porphyrin With Electron-Withdrawing And Hydrophilic Substituents For Improved Electrocatalytic Oxygen Reduction, Hong-Bo Guo, Ya-Ni Wang, Kai Guo, Hai-Tao Lei, Zuo-Zhong Liang, Xue-Peng Zhang, Rui Cao

Journal of Electrochemistry

Understanding factors that influence the catalyst activity for oxygen reduction reaction (ORR) is essential for the rational design of efficient ORR catalysts. Regulating catalyst electronic structure is commonly used to fine-tune electrocatalytic ORR activity. However, modifying the hydrophilicity of catalysts has been rarely reported to improve ORR, which happens at the liquid/gas/solid interface. Herein, we report on two Co porphyrins, namely, NO2-CoP (Co complex of 5,10,15,20-tetrakis(4-nitrophenyl)porphyrin) and 5F-CoP (Co complex of 5,10,15,20-tetrakis(pentafluorophenyl)porphyrin), and their electrocatalytic ORR features. By simultaneously controlling the electronic structure and hydrophilic property of the meso-substituents, the NO2-CoP showed higher electrocatalytic activity than …


Surface Structure Engineering Of Feni-Based Pre-Catalyst For Oxygen Evolution Reaction: A Mini Review, Jia-Xin Li, Li-Gang Feng Sep 2022

Surface Structure Engineering Of Feni-Based Pre-Catalyst For Oxygen Evolution Reaction: A Mini Review, Jia-Xin Li, Li-Gang Feng

Journal of Electrochemistry

Nitrite, a widespread raw material, is harmful to human health for long-term consumption. At present, the detection methods of nitrite mainly include chemical analysis, fluorescence, ultraviolet spectrophotometry and chromatography. These methods have ideal sensitivity and selectivity, but also have some characteristics: cumbersome operation, expensive equipment and professional personnel. Therefore, the development of a simple and sensitive nitrite assay is of great significance. In this paper, the Au/rGO/FeOOH composite materials, which revealed good synergistic catalytic performance among the three elements in the composite, were prepared by simple hydrothermal method and reduction method for the first time with large specific surface area …


Development Of High-Performance Fiber Cement: A Case Study In The Integration Of Circular Economy In Product Design, Parinya Chakartnarodom, Sarunya Wanpen, Wichit Prakaypan, Edward A. Laitila, Nuntaporn Kongkajun Sep 2022

Development Of High-Performance Fiber Cement: A Case Study In The Integration Of Circular Economy In Product Design, Parinya Chakartnarodom, Sarunya Wanpen, Wichit Prakaypan, Edward A. Laitila, Nuntaporn Kongkajun

Michigan Tech Publications, Part 1

A new fiber cement (FC) is designed with the integration of circular economy (CE) concepts, in particular a product that is recyclable yet maintains performance. The FC samples were prepared from the mixtures of ordinary Portland cement (OPC), sand, and cellulose fibers, and required an inclusion compound (IC) and water. From the heat of hydration tests, the most effective IC, IC1, was prepared from lithium silicate, sodium thiocyanate, alkylbenzene sulfonate, and hydrochloric acid. The FC samples were recycled by crushing and grinding, then used as sand replacement in varying amounts to produce new FC samples. The results from the mechanical …


Effect Of Degradation Of Methylene Blue Dye (Mb) By Using Erbium Oxide (Er2o3) Nps, Hind Ahmed Jasim, Farah Farman Abbass, Sarah A. Hamood, Hind Mohammed Hassan, Mohammed Sellab Hamza Sep 2022

Effect Of Degradation Of Methylene Blue Dye (Mb) By Using Erbium Oxide (Er2o3) Nps, Hind Ahmed Jasim, Farah Farman Abbass, Sarah A. Hamood, Hind Mohammed Hassan, Mohammed Sellab Hamza

Al-Esraa University College Journal for Engineering Sciences

In an experiment investigating the photo catalytic degradation of methylene blue using varied concentrations of Er2O3 nanoparticles, different conditions were tested including with and without sunshine, as well as in the absence of a UV source. The presence of a UV source was also considered in the research. UV-Visible spectroscopy was utilized to characterize the catalysts. The degradation of methylene blue dye was monitored by spectrophotometry by tracking dye absorbance at regular time intervals and adjusting the dye concentration. The results indicated that the most effective degradation of methylene blue dye occurred during a 5-hour irradiation time and in the …


Architecture Between Development And Ability Programs, Allaa Ahmed Rasheed, Ibrahim Jawad Kadhim Sep 2022

Architecture Between Development And Ability Programs, Allaa Ahmed Rasheed, Ibrahim Jawad Kadhim

Al-Esraa University College Journal for Engineering Sciences

The development of architecture and its pursuit of perfection can only be achieved through society to reach a specific result when meeting new desires that arise as a result of human development, expanding individual and societal needs, and deepening their relationships in multifaceted ways. The research focuses on development as it requires a clear cumulative vision of the integrative relationship between practice and participation in interpreting the act (effect) from the force (influence). It emphasizes that the power of capabilities is understood through learning and education in describing the capabilities of architecture. This involves adopting new ideas and intellectual premises …


The Designing Of Contemporary Teaching- Learning Spaces According To Interactive Flow Action Local School Spaces-A Case Study, Aseel Jasem Al-Ataby, Anwar Subhi Ramadan Al-Qaraghuli Sep 2022

The Designing Of Contemporary Teaching- Learning Spaces According To Interactive Flow Action Local School Spaces-A Case Study, Aseel Jasem Al-Ataby, Anwar Subhi Ramadan Al-Qaraghuli

Al-Esraa University College Journal for Engineering Sciences

The world today faces many challenges related to environmental issues, as well as other social and economic challenges, and in light of intellectual, cognitive, and technical transformations, which led to the emergence of many new phenomena and concepts that correspond to them, including the concept of flow. This concept has been associated with many aspects of life, including architecture, whose importance has emerged recently in light of the challenge of the spread of the Corona virus and its effects on architecture with its residential, educational, and other spaces. This research focuses on the flow in the architectural space in general, …


A New Compact Triple-Band Micro-Strip Monopole Antenna Based On Minkowski Fractal Geometry, Hayder S. Ahmed, Zahra' Salah Ahmed, Sarah A. Hamood, Mohammed Sellab Hamza, Taha A. Elwi Sep 2022

A New Compact Triple-Band Micro-Strip Monopole Antenna Based On Minkowski Fractal Geometry, Hayder S. Ahmed, Zahra' Salah Ahmed, Sarah A. Hamood, Mohammed Sellab Hamza, Taha A. Elwi

Al-Esraa University College Journal for Engineering Sciences

Wireless communication systems have made significant advancements in size reduction, with antenna terminals remaining a primary challenge for system compatibility. As a result, much of industrial research is focused on antenna miniaturization in wireless systems. In this work, a novel compact Triple-Band Fractal (TBF) antenna is proposed, utilizing three coupling fractal patches with varying iteration levels of Minkowski geometry to provide three resonant bands. The antenna design is implemented using an antenna substrate with a dielectric constant of 10.8 and a thickness of 1.27 mm within the CST Microwave Studio environment. The zero iteration patch resonator is responsible for the …


The Role Of Community Participation In The Architectural Production, Allaa Ahmed Rasheed, Ibrahim Jawad Kadhim Sep 2022

The Role Of Community Participation In The Architectural Production, Allaa Ahmed Rasheed, Ibrahim Jawad Kadhim

Al-Esraa University College Journal for Engineering Sciences

The role of community participation as a power in building architectural output at the level of the act of thinking in architecture and the design process in non-existence is related to power and presence with act. The research is concerned with expanding knowledge in the direction of the holistic language and searching for the role that builds the privacy of the architectural product versus the community's societal identity. It studies the concept of act within the limits of existence at the level of community participation since the act of architecture is the act of man to meet certain needs and …


The Communicative Deviation In Contemporary Architectural Production, Haneen Hosham Abd-Alrahman, Panrizat Q. Hussein Fehmi Sep 2022

The Communicative Deviation In Contemporary Architectural Production, Haneen Hosham Abd-Alrahman, Panrizat Q. Hussein Fehmi

Al-Esraa University College Journal for Engineering Sciences

Deviation is one of the most important concepts discussed in various architectural and non-architectural theses when addressing the topic of creative production. It involves breaking away from the familiar and surpassing established architectural rules to create unique and excellent products that are characterized by their creativity and aesthetic appeal. Recognizing the significance of this concept in shaping contemporary architectural production, the research endeavors to explore the concept of connective displacement in architecture and delve into its essential aspects. The research identifies the research problem as the "cognitive deficiency surrounding connective displacement in the semantic structures embedded in architecture." The objective …


Developed Rc4 Algorithm With Double Reverse For Better Data Protect, Fouad Sahib Muhamed Alkhazraji Sep 2022

Developed Rc4 Algorithm With Double Reverse For Better Data Protect, Fouad Sahib Muhamed Alkhazraji

Al-Esraa University College Journal for Engineering Sciences

Computer security plays a crucial role in protecting users' data, and cryptographic techniques are commonly used for this purpose. Encryption is a method employed to ensure data confidentiality, whether it is stored on hard drives or transferred through various media. RC4 (Rivest Cipher 4) is a cryptographic algorithm that utilizes the same key for both encryption and decryption processes. It falls under the category of stream ciphers, which are widely utilized in numerous protocols due to their flexibility and speed. RC4 employs XOR (exclusive OR) function to implement its encryption and decryption steps. In this paper, a technique known as …


Bio-Based Food Packaging Material For Intelligent Food Packaging Applications For Chicken Fillets, Kalpani Y. Perera, Amit K. Jaiswal, Swarma Jaiswal, Shubham Sharma Sep 2022

Bio-Based Food Packaging Material For Intelligent Food Packaging Applications For Chicken Fillets, Kalpani Y. Perera, Amit K. Jaiswal, Swarma Jaiswal, Shubham Sharma

Articles

Bionanocomposite packaging is made up of bio- based materials that have high performance activity and are ecologically sustainable alternatives to packaging made of synthetic polymers. Intelligent packaging retains track of the state of the food and the environment in which it is stored, and communicates relevant changes to the consumer through visualization or other methods. The aim of this study was to develop a bionanocomposite intelligent packaging material by utilising sodium alginate, gelatin, nanoclay and curcumin. Sodium alginate, gelatin film incorporated with Curcumin (Cur), and Nanoclay (NC) in various concentrations (0% W/V, 0.5% W/V, 1% W/V and 1. 5% W/V) …


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, Part 1

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 …


An Experimental Study Of Norton And Thule Cooking Pot Performance, Caelie Marshall Butler Sep 2022

An Experimental Study Of Norton And Thule Cooking Pot Performance, Caelie Marshall Butler

Dissertations and Theses

Ceramic technology was adopted by hunter-gatherers of the Paleo-Inuit Norton tradition in the Western Arctic between 2800 and 2500 years B.P., corresponding with an increase in the use of aquatic resources. Pottery production and use continued until approximately 1,500 BP, and resumed during the Neo-Inuit Birnirk and Thule periods, approximately 1,350 years BP. The technical characteristics of Norton and Thule ceramics suggest they performed differently when used for cooking, with Norton ceramics best suited for cooking using direct or suspended heat, and Thule ceramics best suited for indirect heat. Prior experimental archaeological research has focused on Thule ceramics, with limited …


Solar Pv Panels-Self-Cleaning Coating Material For Egyptian Climatic Conditions, Iman El-Mahallawi, Engy Elshazly, Olugbenga Timo Oladinrin Dr., Muhammad Qasim Rana Dr. Sep 2022

Solar Pv Panels-Self-Cleaning Coating Material For Egyptian Climatic Conditions, Iman El-Mahallawi, Engy Elshazly, Olugbenga Timo Oladinrin Dr., Muhammad Qasim Rana Dr.

Renewable Mechanical Energy

No abstract provided.


Study Of Asymptotic Velocity In The Bondi–Hoyle Accretion Flows In The Domain Of Kerr And 4-D Einstein–Gauss–Bonnet Gravities, Orhan Donmez, Fatih Dogan, Tuba Sahin Sep 2022

Study Of Asymptotic Velocity In The Bondi–Hoyle Accretion Flows In The Domain Of Kerr And 4-D Einstein–Gauss–Bonnet Gravities, Orhan Donmez, Fatih Dogan, Tuba Sahin

Materials Science and Engineering Faculty Research & Creative Works

Understanding the physical structures of the accreted matter very close to a black hole in quasars and active galactic nucleus (AGN) is an important milestone to constrain the activities occurring in their centers. In this paper, we numerically investigate the effects of the asymptotic velocities on the physical structures of the accretion disk around the Kerr and Einstein–Gauss–Bonnet (EGB) rapidly rotating black holes. The Bondi–Hoyle accretion is considered with a falling gas towards the black hole in an upstream region of the computational domain. Shock cones are naturally formed in the downstream part of the flow around both black holes. …


Elucidating The Interfacial Bonding Behavior Of Over-Molded Hybrid Fiber Reinforced Polymer Composites: Experiment And Multiscale Numerical Simulation, Gideon A. Lyngdoh, Sumanta Das Sep 2022

Elucidating The Interfacial Bonding Behavior Of Over-Molded Hybrid Fiber Reinforced Polymer Composites: Experiment And Multiscale Numerical Simulation, Gideon A. Lyngdoh, Sumanta Das

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

This paper implements molecular dynamics (MD) simulation using reactive force field (ReaxFF) to evaluate the

atomistic origin of the interfacial behavior in the overmolded hybrid unidirectional continuous carbon fiber low-melt PAEK (CFR- LMPAEK)-short carbon fiber reinforced PEEK (SFR-PEEK) polymer composites. From the MD simulation, it was observed that the

interfacial properties improve with increasing maximum processing temperature and injection pressure although such an improving trajectory gets saturated beyond specific limits. The interfacial strength and fracture response of the hybrid polymer system at the interface are also evaluated. The mechanical responses obtained from MD simulation are used as adhesive properties in …


Irradiation-Induced Amorphous-To-Crystalline Phase Transformations In Ceramic Materials, Cyrus Koroni, Tristan Olsen, Janelle P. Wharry, Hui Xiong Sep 2022

Irradiation-Induced Amorphous-To-Crystalline Phase Transformations In Ceramic Materials, Cyrus Koroni, Tristan Olsen, Janelle P. Wharry, Hui Xiong

Materials Science and Engineering Faculty Publications and Presentations

Amorphous ceramics are a unique class of materials with unusual properties and functionalities. While these materials are known to crystallize when subjected to thermal annealing, they have sometimes been observed to crystallize athermally when exposed to extreme irradiation environments. Because irradiation is almost universally understood to introduce disorder into materials, these observations of irradiation-induced ordering or crystallization are unusual and may partially explain the limited research into this phenomenon. However, the archival literature presents a growing body of evidence of these irradiation-induced amorphous-to-crystalline (a-to-c) phase transformations in ceramics. In this perspective, the summary and review of examples from the literature …


Developing Scaling Laws To Predict Compressive Mechanical Properties And Determine Geometrical Parameters Of Modified Bcc Lattice Structures, Hasanain Abdulhadi, Abdalsalam Fadeel, Tahseen A. Alwattar, Ahsan Mian Sep 2022

Developing Scaling Laws To Predict Compressive Mechanical Properties And Determine Geometrical Parameters Of Modified Bcc Lattice Structures, Hasanain Abdulhadi, Abdalsalam Fadeel, Tahseen A. Alwattar, Ahsan Mian

Mechanical and Materials Engineering Faculty Publications

The objective of this study is to develop generalized empirical closed-form equations to predict the compressive mechanical properties and determine geometrical parameters. To achieve that, 117 models are built and analyzed using ABAQUS/CAE 2016 to provide two types of reliable data: one for lattice mechanical properties based on finite element method and the other for geometrical parameters using the measurements of ABAQUS diagnostic tool. All the models are created by modifying the basic feature of body-centered cubic lattice structure based on a range of strut angles, a set of relative densities, and two design sets. Also, the influence of lattice …


Global Tellurium Supply Potential From Electrolytic Copper Refining, Nedal T. Nassar, Haeyeon Kim, Max Frenzel, Michael S. Moats, Sarah M. Hayes Sep 2022

Global Tellurium Supply Potential From Electrolytic Copper Refining, Nedal T. Nassar, Haeyeon Kim, Max Frenzel, Michael S. Moats, Sarah M. Hayes

Materials Science and Engineering Faculty Research & Creative Works

The transition towards renewable energy requires increasing quantities of nonfuel mineral commodities, including tellurium used in certain photovoltaics. While demand for tellurium may increase markedly, the potential to increase tellurium supply is not well-understood. In this analysis, we estimate the quantity of tellurium contained in anode slimes generated by electrolytic copper refining by country between 1986 and 2018, including uncertainties. For 2018, the results indicate that 1930 (1500-2700, 95% confidence interval) metric tons of tellurium were contained in anode slimes globally. This is nearly quadruple the reported tellurium production for that year. China has the greatest potential to increase tellurium …


High-Entropy Boride–Carbide Ceramics By Sequential Boro/Carbothermal Synthesis, Steven M. Smith, Lun Feng, William Fahrenholtz, Greg Hilmas, Tieshu Huang Sep 2022

High-Entropy Boride–Carbide Ceramics By Sequential Boro/Carbothermal Synthesis, Steven M. Smith, Lun Feng, William Fahrenholtz, Greg Hilmas, Tieshu Huang

Materials Science and Engineering Faculty Research & Creative Works

A dual-phase high-entropy boride (HEB)/carbide (HEC) ceramic with a fine grain size was synthesized by a sequential boro/carbothermal process. In the first step, an Hf–Nb–Ta–Ti–Zr-containing carbide was synthesized by a carbothermal reduction of oxides followed by the reaction of the carbide with B4C and ZrH2 to convert part of the carbide to boride. The resulting composition was ∼29 vol% HEB with an average grain size of ∼1.1 μm. Solid solution formation occurred at the densification temperature of 1900°C resulting in a relative density higher than 99%. The Vickers hardness was 26.5 ± 1.4 GPa. This is the first report of …


Improved Additive Manufacturing Of Silicon Carbide Parts Via Pressureless Electric Field-Assisted Sintering, Adam Bratten, Ruoyu Chen, Joshua Rittenhouse, Ming-Chuan Leu, Haiming Wen Sep 2022

Improved Additive Manufacturing Of Silicon Carbide Parts Via Pressureless Electric Field-Assisted Sintering, Adam Bratten, Ruoyu Chen, Joshua Rittenhouse, Ming-Chuan Leu, Haiming Wen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

High solids loading silicon carbide (SiC)-based aqueous slurries containing only.5 wt. % organic additives were utilized to create specimens of various geometries via an extrusion-based additive manufacturing (AM) technique. Pressure less electric field-assisted sintering was performed to densify each specimen without deformation. The combination of these techniques produced parts with >98% relative density despite containing only 5 wt.% oxide sintering additives. After sintering, specimens contained only the α-SiC and yttrium aluminum perovskite phases. This suggests the evolution of a nonequilibrium yttrium aluminate phase, as well as transformation from β-SiC to α-SiC. The fabrication method presented in this work has advantages …


Effect Of Rolling Process On Magnetic Properties Of Fe-3.3 Wt% Si Non-Oriented Electrical Steel, Yizhou Du, Ronald J. O'Malley, Mario F. Buchely, Paul Kelly Sep 2022

Effect Of Rolling Process On Magnetic Properties Of Fe-3.3 Wt% Si Non-Oriented Electrical Steel, Yizhou Du, Ronald J. O'Malley, Mario F. Buchely, Paul Kelly

Materials Science and Engineering Faculty Research & Creative Works

In this study, the influence of the rolling process on magnetic properties of Fe-3.3 wt% Si non-oriented electrical steel was investigated. The strip samples were cast using a high solidification cooling rate vacuum sampling method to simulate the solidification conditions of the industrial twin roll thin strip casting (TRSC) process. As-cast samples were subjected to various thermo-mechanical processing routes with different levels of hot-rolling (HR) and cold-rolling (CR). The influence of carbon and sulfur (C&S) contents in the steel were also investigated. Core loss (P1.5/50, P1.5/60, P1.0/50, P1.0/60) and magnetic induction (B25, B50) of the final annealed strip samples were …


Mechanical Activation And Cation Site Disorder In Mgal2o4, Cole A. Corlett, Matthias D. Frontzek, Nina Obradovic, Jeremy Lee Watts, William Fahrenholtz Sep 2022

Mechanical Activation And Cation Site Disorder In Mgal2o4, Cole A. Corlett, Matthias D. Frontzek, Nina Obradovic, Jeremy Lee Watts, William Fahrenholtz

Materials Science and Engineering Faculty Research & Creative Works

The synthesis and crystallographic site occupancy were investigated for MgAl2O4 with and without mechanical activation of the precursor powders. Heating to 1200 °C or higher resulted in the formation of a single spinel phase regardless of whether the powders were mechanically activated or not. Neutron diffraction analysis was used to determine cation site occupancy and revealed that mechanical activation resulted in a lower degree of cation site inversion compared to the nonactivated materials, which indicated that the powders were closer to thermodynamic equilibrium. This is the first study to characterize the effects of mechanical activation on crystallographic site occupancy in …


Ultrafast Stiffening Of Concentrated Thermoresponsive Mineral Suspensions, Sharu Bhagavathi Kandy, Iman Mehdipour, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Samanvaya Srivastava, Torben Gaedt, Gaurav Sant Sep 2022

Ultrafast Stiffening Of Concentrated Thermoresponsive Mineral Suspensions, Sharu Bhagavathi Kandy, Iman Mehdipour, Narayanan Neithalath, Aditya Kumar, Mathieu Bauchy, Edward Garboczi, Samanvaya Srivastava, Torben Gaedt, Gaurav Sant

Materials Science and Engineering Faculty Research & Creative Works

Extrusion-based 3D printing with rapidly hardening polymeric materials is capable of building almost any conceivable structure. However, concrete, one of the most widely used materials for large-scale structural components, is generally based on inorganic binder materials like Portland cement. Unlike polymeric materials, a lack of precise control of the extent and rate of solidification of cement-based suspensions is a major issue that affects the ability to 3D-print geometrically complex structures. Here, we demonstrate a novel method for controllable-rapid solidification of concentrated mineral suspensions that contain a polymer binder system based on epoxy and thiol precursors as well as one or …


Processing And Mechanical Properties Of Hot-Pressed Zirconium Diboride – Zirconium Carbide Ceramics, Eric W. Neuman, William Fahrenholtz, Gregory E. Hilmas Sep 2022

Processing And Mechanical Properties Of Hot-Pressed Zirconium Diboride – Zirconium Carbide Ceramics, Eric W. Neuman, William Fahrenholtz, Gregory E. Hilmas

Materials Science and Engineering Faculty Research & Creative Works

ZrB2 was mixed with 0.5 wt% carbon and up to 10 vol% ZrC and densified by hot-pressing at 2000 °C. All compositions were > 99.8% dense following hot-pressing. The dense ceramics contained 1–1.5 vol% less ZrC than the nominal ZrC addition and had between 0.5 and 1 vol% residual carbon. Grain sizes for the ZrB2 phase decreased from 10.1 µm for 2.5 vol% ZrC to 4.2 µm for 10 vol% ZrC, while the ZrC cluster size increased from 1.3 µm to 2.2 µm over the same composition range. Elastic modulus was ~505 GPa and toughness was ~2.6 MPa·m½ for all compositions. …


Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd Sep 2022

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …


Influence Of Defects On In-Plane Dynamic Properties Of Hexagonal Ligament Chiral Structures, Ning An, Xunwen Su, Dongmei Zhu, Mileta M. Tomovic Sep 2022

Influence Of Defects On In-Plane Dynamic Properties Of Hexagonal Ligament Chiral Structures, Ning An, Xunwen Su, Dongmei Zhu, Mileta M. Tomovic

Engineering Technology Faculty Publications

Although the six-ligament chiral structure has many unique properties, due to its special structure, the stress concentration is prone to defects. In addition, additive manufacturing is also prone to defects. This paper studies the effect of defects, which is helpful for the better application of the six-ligament chiral structure. Several new six-ligament chiral structures with random and concentrated defects were designed to explore the effects of the defects on the in-plane dynamic properties. The structures were studied with the finite element ANSYS/LSDYNA numerical simulation and experimental methods. According to the defect-free six-ligament chiral structures exhibiting different deformation modes at different …


Mechanical Properties And Tension-Tension Fatigue Behavior Of A Novel Additively Manufactured Polymer Matrix Composite At Room And Elevated Temperature, Grayson M. Harber Sep 2022

Mechanical Properties And Tension-Tension Fatigue Behavior Of A Novel Additively Manufactured Polymer Matrix Composite At Room And Elevated Temperature, Grayson M. Harber

Theses and Dissertations

The tension-tension fatigue behavior of a novel additively manufactured AM carbon fiber reinforced polymer matrix composite was studied. This novel material system consists of T1100 carbon fibers, and a UV photocured resin developed by Continuous Composites and Sartomer. Tensile properties and tension-tension fatigue were investigated for the 090 fiber orientation as well as for the ±45 fiber orientation. Specimens with 0/90 fiber orientation were tested at ambient laboratory temperature 23 °C and at elevated temperature 150 °C, while the specimens with the ±45 fiber orientation were tested only at ambient laboratory temperature. Tension-tension fatigue testing was carried out with a …


Effect Of Current Density Ramping On The Anodic Reaction And Morphology Of Aerospace Aluminum Alloys, Peter Totaro Jr. Aug 2022

Effect Of Current Density Ramping On The Anodic Reaction And Morphology Of Aerospace Aluminum Alloys, Peter Totaro Jr.

Dissertations

Aluminum anodizing has been experimented with and studied over the last century because of its ability to form uniform, well ordered cellular coatings on aluminum alloys. Anodizing aerospace alloys has been problematic, due to the alloying elements used to add strength and resistance to stress cracking corrosion. These intermetallic compounds, i.e., copper and zinc, promote oxygen evolution and stress as they accumulate in and on the surface of the forming aluminum oxide. These inclusions lead to increased electrical resistance that forms porous and flawed coating, which can lead to industrial and field failures. The amount of voltage placed on the …