Tensile Strength Of Materials Obtained By Electric Pulse Consolidation Of Powders,
2019
ISMAN, Russia
Tensile Strength Of Materials Obtained By Electric Pulse Consolidation Of Powders, Evgeny Grigoryev, Vladimir Goltsev, Andrey Osintsev, Aleksandr Plotnikov
Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities
A wide range of products of modern technology, obtained by electropulse consolidation of powders, has dimensions that do not exceed 10-15 mm in diameter, and their thickness varies from 1 to 10 mm. Standard mechanical testing methods for such sample sizes are often not applicable.
The article investigates the possibility of determining the resistance to fracture of materials obtained from powders by electric pulse consolidation method using the test method for bending thin disks on an annular support and testing short cylinders according to the "Brazilian test". A numerical simulation of the process of bending a thin disk on an …
Microstructure Evolution During High-Pressure Spark Plasma Sintering (Hpsps) Of Transparent Alumina,
2019
Ben-Gurion University of the Negev, Israel
Microstructure Evolution During High-Pressure Spark Plasma Sintering (Hpsps) Of Transparent Alumina, Barak Ratzker, Sergey Kalabukhov, Nachum Frage, Avital Wagner
Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities
Applying high-pressure during spark plasma sintering (so-called HPSPS) enables rapid densification of a ceramic powder at relatively lower temperatures, limiting grain growth and allowing fabrication of fine-grained highly transparent ceramics. The present work focuses on the fabrication of fine submicron transparent alumina from untreated commercial powder by HPSPS and the microstructure evolution during consolidation under high applied pressure. The sintering was conducted at relatively low temperatures (1000-1100°C) under high pressure varied from 250 to 800 MPa. We review unique sintering phenomena such as stress-enhanced grain growth and de-sintering, which are related to creep taking place during the final stage of …
Conference Program,
2019
University of Colorado, USA
Conference Program, Rishi Raj, Olivier Guillon, Hidehiro Yoshida
Electric Field Enhanced Processing of Advanced Materials II: Complexities and Opportunities
No abstract provided.
Latex Modified Concrete - Very Early Strength,
2019
Purdue University
Latex Modified Concrete - Very Early Strength, Bobby Steele
Purdue Road School
INDOT came out with specifications for a very early strength concrete to use on bridge deck overlays. This concrete is fast setting, which allows overlays to be performed over a weekend and benefits the traveling public with a short duration of traffic interference. Cure time to reach the strength requirement is 3 hours. E&B Paving performed the first application with the new spec on August 26, 2018. Many changes were also made to the INDOT Specification Section 722.
Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System,
2019
Technological University Dublin
Microwave Self-Healing Technology As Airfield Porous Asphalt Friction Course Repair And Maintenance System, Amir Tabakovic, Declan O'Prey, Drew Mckenna, David Woodward
Research and Innovation - Articles
A problem increasingly faced by airport authorities is the maintenance of runways. Due to their large aircraft loadings associated with take-off and landing operations, runways experience surface deterioration. Poor quality runway surfaces cannot be tolerated in such an environment. Maintenance issues must be carried out to maximise safety and minimise the risk of aircraft damage. A recent development has been the introduction of self-healing technologies such as rejuvenator encapsulation, induction and microwave heating to address these issues. This paper summarises a laboratory investigation to determine the effectiveness of microwave self-healing for crack repair of Porous Friction Course (PFC) used for …
Thermal Transport In Layer-By-Layer Assembled Polycrystalline Graphene Films,
2019
Boise State University
Thermal Transport In Layer-By-Layer Assembled Polycrystalline Graphene Films, David Estrada, Alondra Perez
Materials Science and Engineering Faculty Publications and Presentations
New technologies are emerging which allow us to manipulate and assemble 2-dimensional (2D) building blocks, such as graphene, into synthetic van der Waals (vdW) solids. Assembly of such vdW solids has enabled novel electronic devices and could lead to control over anisotropic thermal properties through tuning of inter-layer coupling and phonon scattering. Here we report the systematic control of heat flow in graphene-based vdW solids assembled in a layer-by-layer (LBL) fashion. In-plane thermal measurements (between 100 K and 400 K) reveal substrate and grain boundary scattering limit thermal transport in vdW solids composed of one to four transferred layers of …
Roadmap On Biological Pathways For Electronic Nanofabrication And Materials,
2019
Boise State University
Roadmap On Biological Pathways For Electronic Nanofabrication And Materials, Reza M. Zadegan
Materials Science and Engineering Faculty Publications and Presentations
Conventional microchip fabrication is energy and resource intensive. Thus, the discovery of new manufacturing approaches that reduce these expenditures would be highly beneficial to the semiconductor industry. In comparison, living systems construct complex nanometer-scale structures with high yields and low energy utilization. Combining the capabilities of living systems with synthetic DNA-/protein-based self-assembly may offer intriguing potential for revolutionizing the synthesis of complex sub-10 nm information processing architectures. The successful discovery of new biologically based paradigms would not only help extend the current semiconductor technology roadmap, but also offer additional potential growth areas in biology, medicine, agriculture and sustainability for the …
Effects Of Steel Type And Sandblasting Pretreatment On The Solid-Liquid Compound Casting Characteristics Of Zinc-Coated Steel/Aluminum Bimetals,
2019
Korea Institute of Industrial Technology
Effects Of Steel Type And Sandblasting Pretreatment On The Solid-Liquid Compound Casting Characteristics Of Zinc-Coated Steel/Aluminum Bimetals, Jesik Shin, Taehyeong Kim, Kyoungmook Lim, Hoon Cho, Daeho Yang, Changyeol Jeong, Sung Yi
Mechanical and Materials Engineering Faculty Publications and Presentations
Effects of zinc-coated steel type and steel surface sandblasting pretreatment in the solid-liquid compound casting of layered type steel/aluminum bimetals were investigated. The Zn coating behavior and its effects on interfacial microstructure evolution and fracture mechanism were also discussed. The aluminum fluidity in thin plate type flow channels formed by the steel insert and the mold wall primarily depended on the insert surface roughness and secondarily on the wettability. As-galvanized (GI) steel/aluminum bimetal joints showed the bonding strength of 20 MPa and more, while galvannealed (GA) steels showed poor bonding. The interfacial bonding zone consisted of most Al13Fe4, Al8Fe2Si, Al4.5FeSi …
Deformation Mechanisms In Mg–Al Nanocomposite,
2019
University of Nebraska-Lincoln
Deformation Mechanisms In Mg–Al Nanocomposite, Soodabeh Azadehranjbar, Jian Wang, Jeffrey E. Shield
Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research
Magnesium is the lightest engineering metal. Replacing steel with Mg based materials in automotive applications would lead to more than 40% weight reduction which significantly boost fuel efficiency. However, conventional Mg alloys typically suffer from low strength and poor deformability due to very few slip systems and easy twinning. Alloying Mg with other materials and microstructural engineering are promising approaches to increase ductility and strength of Mg According to Wang et al. interfaces with low energy and high coherency may effectively constrict the nucleation of twins in Mg In this work, the microstructure of Mg nano layers and nano rods …
On The Feasibility Of Tailoring Copper-Nickel Functionally Graded Materials Fabricated Through Laser Metal Deposition,
2019
Missouri University of Science and Technology
On The Feasibility Of Tailoring Copper-Nickel Functionally Graded Materials Fabricated Through Laser Metal Deposition, Sreekar Karnati, Yunlu Zhang, Frank W. Liou, Joseph William Newkirk
Mechanical and Aerospace Engineering Faculty Research & Creative Works
In this study, pulse‐width modulation of laser power was identified as a feasible means for varying the chemical gradient in copper—nickel‐graded materials. Graded material deposits of 70 wt. %. copper‐30 wt. %. nickel on 100 wt. %. nickel and vice versa were deposited and characterized. The 70/30 copper—nickel weight ratio in the feedstock powder was achieved through blending elemental copper and 96 wt. %. Ni—Delero‐22 alloy. At the dissimilar material interface over the course of four layers, the duty cycle of power was ramped down from a high value to optimized deposition conditions. This change was theorized to influence the …
Corrosion Initiation And Propagation On Carburized Martensitic Stainless Steel Surfaces Studied Via Advanced Scanning Probe Microscopy,
2019
Boise State University
Corrosion Initiation And Propagation On Carburized Martensitic Stainless Steel Surfaces Studied Via Advanced Scanning Probe Microscopy, Armen Kvryan, Corey M. Efaw, Kari A. Higginbotham, Olivia O. Maryon, Paul H. Davis, Elton Graugnard, Michael F. Hurley
Materials Science and Engineering Faculty Publications and Presentations
Historically, high carbon steels have been used in mechanical applications because their high surface hardness contributes to excellent wear performance. However, in aggressive environments, current bearing steels exhibit insufficient corrosion resistance. Martensitic stainless steels are attractive for bearing applications due to their high corrosion resistance and ability to be surface hardened via carburizing heat treatments. Here three different carburizing heat treatments were applied to UNS S42670: a high-temperature temper (HTT), a low-temperature temper (LTT), and carbo-nitriding (CN). Magnetic force microscopy showed differences in magnetic domains between the matrix and carbides, while scanning Kelvin probe force microscopy (SKPFM) revealed a 90–200 …
Thermographic Laplacian-Pyramid Filtering To Enhance Delamination Detection In Concrete Structure,
2019
University of Delaware
Thermographic Laplacian-Pyramid Filtering To Enhance Delamination Detection In Concrete Structure, Chongsheng Cheng, Ri Na, Zhigang Shen
Department of Construction Engineering and Management: Faculty Publications
Despite decades of efforts using thermography to detect delamination in concrete decks, challenges still exist in removing environmental noise from thermal images. The performance of conventional temperature-contrast approaches can be significantly limited by environment-induced non-uniform temperature distribution across imaging spaces. Time-series based methodologies were found robust to spatial temperature non-uniformity but requires extended period to collect data. A new empirical image filtering method is introduced in this paper to enhance the delamination detection using blob detection method that originated from computer vison. The proposed method employs a Laplacian of Gaussian filter to achieve multi-scale detection of abnormal thermal patterns by …
To Burn-In, Or Not To Burn-In: That’S The Question,
2019
Portland State University
To Burn-In, Or Not To Burn-In: That’S The Question, Ephraim Suhir
Mechanical and Materials Engineering Faculty Publications and Presentations
In this paper it is shown that the bathtub-curve (BTC) based time-derivative of the failure rate at the initial moment of time can be considered as a suitable criterion of whether burn-in testing (BIT) should or does not have to be conducted. It is also shown that the above criterion is, in effect, the variance of the random statistical failure rate (SFR) of the mass-produced components that the product manufacturer received from numerous vendors, whose commitments to reliability were unknown, and their random SFR might vary therefore in a very wide range, from zero to infinity. A formula for the …
Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials,
2019
Air Force Institute of Technology
Computational And Experimental Development Of 2d Anisotropic Photonic Crystal Metamaterials, James A. Ethridge
Theses and Dissertations
The future of optical devices involves manipulation of nanoscale structure in order to achieve full control over the properties of the device. In fields as diverse as directed energy, remote sensing, optical communications and optical computing, these devices promise to greatly improve performance and efficiency. To advance this further, novel samples that incorporate both photonic crystal (PhC) structure and metamaterial properties, known as PhC metamaterials, are proposed. These PhC metamaterials allow for complete control over the directionality of the light-matter interaction to serve in these new applications. To develop this technology, first, metamaterials with no PhC structure are fabricated using …
Current Status And Prospect Of Battery Configuration In Li-S System,
2019
Department of Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
Current Status And Prospect Of Battery Configuration In Li-S System, Jia-Hang Chen, Hui-Jun Yang, Cheng Guo, Jiu-Lin Wang
Journal of Electrochemistry
Commercial lithium-ion batteries (LIBs) are incapable of satisfying the increasing demand for emerging electronic devices due to their limited energy density. Among the next-generation batteries, lithium-sulfur (Li-S) batteries are becoming a promising energy-storage system due to their high theoretical energy density and natural abundance of sulfur. However, the shuttle of soluble polysulfide intermediates between two electrodes, as well as the problem on Li metal anode,lower the utilization of active material and lead to the loss of specific capacity and rapid capacity fading. All the above challenges limit the further application of Li-S batteries. Recently, various novel battery configurations have been …
A Comparative Study Of Pre-Lithiated Hard Carbon And Soft Carbon As Anodes For Lithium-Ion Capacitors,
2019
Key Laboratory of Applied Superconductivity, Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, P. R. China;
A Comparative Study Of Pre-Lithiated Hard Carbon And Soft Carbon As Anodes For Lithium-Ion Capacitors, Zhao Li, Xian-Zhong Sun, Wen-Jie Liu, Xiong Zhang, Kai Wang, Yan-Wei Ma
Journal of Electrochemistry
Lithium-ion capacitor (LIC) has emerged to be one of the most promising electrochemical energy storage devices. Presently, activated carbon (AC) is the mostly used cathode material for LIC. Nevertheless, various carbonaceous materials can be used as anode materials, such as hard carbon (HC) and soft carbon (SC). Therefore, HC and SC with different structural and electrochemical characteristics have been investigated as the anode materials of LICs in this work. Compared with the HC electrode, the SC electrode showed higher electronic conductivity and reversible capacity. The rate capabilities of the two carbonaceous materials as a function of coating thickness have been …
Cvd Preparation And Application Of 3d Graphene In Electrochemical Energy Storage,
2019
School of Physics and Electronics, Hunan University, Changsha 410082, China;
Cvd Preparation And Application Of 3d Graphene In Electrochemical Energy Storage, Yong-Kang Xia, Ming-Yuan Gu, Hong-Guan Yang, Xin-Zhi Yu, Bing-An Lu
Journal of Electrochemistry
Three-dimensional (3D) graphene combinations with the excellent intrinsic properties of graphene and the 3D micro/nano porous structures provide a graphene foam with high specific surface area, excellent mechanical strength and fast electron and mass transports. The 3D graphene foam and its composite nanomaterials are widely used in the fields of nano-electronics, energy storage, chemical and biological sensing. The 3D graphene foam prepared by chemical vapor deposition (CVD) method is of high purity and crystallinity. In this review, a brief overview in the CVD preparations of 3D graphene and properties of CVD prepared 3D graphene based nanomaterials in electrochemical energy storage …
Applications Of Advanced Imaging Technologies For Critical Issues Of All-Solid-State Lithium Battery Studies,
2019
UM-SJTU Joint Institutee, Shanghai Jiao Tong University, Shanghai, 200240, China;
Applications Of Advanced Imaging Technologies For Critical Issues Of All-Solid-State Lithium Battery Studies, Yi-Bo Zhao, Hui-Hui Liu, Song-Liang Chen, Shou-Hang Bo
Journal of Electrochemistry
All-solid-state lithium batteries have attracted much attention for their high energy density and good safety. To increase their efficiency and prolong their service life, it is necessary to achieve high ion conductivity at the electrode/electrolyte interface and in the electrolyte, as well as to eliminate dendrites growth in the battery. Based on the critical requirements outlined above, this paper discusses the applications of advanced imaging technologies in relevant studies. Recent progresses in investigations of all-solid-state lithium batteries by imaging techniques including electron microscopy, scanning probe microscopy, X-ray tomography, magnetic resonance imaging and optical microscopy are summarized.
Ni/Mn3O4/Nimn2O4 Double-Shelled Hollow Spheres Embedded Into Reduced Graphene Oxide As Advanced Anodes For Sodium-Ion Batteries,
2019
1. Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387, China; 2. Institute of Advanced Electrochemical Energy & School of Materials Science and Engineering, Xi’an University of;
Ni/Mn3O4/Nimn2O4 Double-Shelled Hollow Spheres Embedded Into Reduced Graphene Oxide As Advanced Anodes For Sodium-Ion Batteries, Chong Yan, Hua-Ri Kou, Bo Yan, Xiao-Jing Liu, De-Jun Li, Xi-Fei Li
Journal of Electrochemistry
Delicately building the unique nanocomposite with the combination of hollow structure and reduced graphene oxide (rGO) is highly desirable and still remains a great challenge in the field of energy conversion and storage. In this work, Ni/Mn3O4/NiMn2O4 double-shelled hollow spheres coated by rGO (denoted as R-NMN) have been successfully synthetized via one-step rapid solvothermal treatment followed by subsequent annealing for the first time. Served as anodes for sodium ion batteries (SIBs), the R-NMN composite containing 25wt% rGO exhibits a high discharge capacity of 187.8 mAh·g-1 after 100 cycles at 50 mA·g-1 …
Preface On Special Issue Of Next-Generation Secondary Batteries,
2019
School of Materials Science and Engineering, Nankai University, Tianjin, China
Preface On Special Issue Of Next-Generation Secondary Batteries, Zhen Zhou, Quan-Feng Dong
Journal of Electrochemistry
No abstract provided.
