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Full-Text Articles in Engineering Science and Materials

Liquid Metal-Elastomer Soft Composites With Independently Controllable And Highly Tunable Droplet Size And Volume Loading, Ravi Tutika, Steven Kmiec, A. B. M. Tahidul Haque, Steve W. Martin, Michael D. Bartlett May 2019

Liquid Metal-Elastomer Soft Composites With Independently Controllable And Highly Tunable Droplet Size And Volume Loading, Ravi Tutika, Steven Kmiec, A. B. M. Tahidul Haque, Steve W. Martin, Michael D. Bartlett

Michael Bartlett

Soft composites are critical for soft and flexible materials in energy harvesting, actuators, and multifunctional devices. One emerging approach to create multifunctional composites is through the incorporation of liquid metal (LM) droplets such as eutectic gallium indium (EGaIn) in highly deformable elastomers. The microstructure of such systems is critical to their performance, however, current materials lack control of particle size at diverse volume loadings. Here, we present a fabrication approach to create liquid metal-elastomer composites with independently controllable and highly tunable droplet size (100 nm ≦ D ≦ 80 μm) and volume loading (0 ≦ φ ≦ 80%). This is …


Nickel Based Rtd Fabricated Via Additive Screen Printing Process For Flexible Electronics, Vikram S. Turkani, Dinesh Maddipatla, Binu B. Narakathu, Bilge N. Altay, Paul D. Fleming, Bradley J. Bazuin, Massood Atashbar Feb 2019

Nickel Based Rtd Fabricated Via Additive Screen Printing Process For Flexible Electronics, Vikram S. Turkani, Dinesh Maddipatla, Binu B. Narakathu, Bilge N. Altay, Paul D. Fleming, Bradley J. Bazuin, Massood Atashbar

Bilge Nazli Altay

A novel nickel (Ni) based resistance temperature detector (RTD) was successfully developed for temperature monitoring applications. The RTD was fabricated by depositing Ni ink on a flexible polyimide substrate using the screen printing process. Thermogravimetric analysis was performed to study the thermal behavior of the Ni ink and it was observed that the Ni ink can withstand up to 200°C before decomposition of the binder in the ink system. Scanning electron microscopy and white light interferometry were used to analyze the surface morphology of the printed Ni. X-ray diffractometry was used to obtain structural information, phase and crystallite size of …


Investigation Of The Evolution Of Hydrophobicity And Wettability Of Paper In Multi-Color Printing Process, C Aydemir, A Karademir, S Imamoglu, Bilge N. Altay, Paul D. Fleming, D Tutak Dec 2018

Investigation Of The Evolution Of Hydrophobicity And Wettability Of Paper In Multi-Color Printing Process, C Aydemir, A Karademir, S Imamoglu, Bilge N. Altay, Paul D. Fleming, D Tutak

Bilge Nazli Altay

One of the keys to improving print quality is to experimentally characterize the paper surface, structure and printability to obtain quality control mechanisms. In multi-color prints, determining the differences in the acceptance of the next color ink by the surface of the paper or the ink film that was previously printed is important for print quality. The criteria, such as ink setting, adhesion, color, gloss and density, in the printing process, depend on the wettability and absorbency of the paper. The surface structure of the paper is the most important factor in determining the hydrophobic properties. In this study, wetting …


Tailoring Materials Behavior Using Geometry.Pdf, Hessein Ali, Hossein Ebrahimi, Ranajay Ghosh Dec 2018

Tailoring Materials Behavior Using Geometry.Pdf, Hessein Ali, Hossein Ebrahimi, Ranajay Ghosh

Hossein Ebrahimi

Many applications require materials whose response can be tuned such as morphing wings for super maneuverable vehicles, soft robotics and space structures. Nature achieves this objective using external dermal features – skin, furs, tooth, feathers. These nonlinearities are generated using the geometry and topology of the scales. The scales provide distinct structural advantages such as protection and tailorable response from scales contact. Scales also aid in highly dynamic life functions – such as locomotion, anti anti-fouling, flapping flights, swimming. Material to structural correlations are highly nonlinear due to scale topology. We aim to reveal structure structure-propertyproperty-architecture correlations for automated 3D …


Impact Of Substrate And Process On The Electrical Performance Of Screen-Printed Nickel Electrodes: Fundamental Mechanism Of Ink Film Roughness, Bilge N. Altay, Jerome Jourdan, Vikram S. Turkani, Hervé Dietsch, Dinesh Maddipatla, Alexandra Pekarovicova, Paul D. Fleming, Massood Atashbar Nov 2018

Impact Of Substrate And Process On The Electrical Performance Of Screen-Printed Nickel Electrodes: Fundamental Mechanism Of Ink Film Roughness, Bilge N. Altay, Jerome Jourdan, Vikram S. Turkani, Hervé Dietsch, Dinesh Maddipatla, Alexandra Pekarovicova, Paul D. Fleming, Massood Atashbar

Bilge Nazli Altay

In recent years, traditional printing methods have been integrated to print flexible electronic devices and circuits. Since process requirements for electronics diff er from those for graphic printing, the fundamentals require rediscovery mainly to optimize manufacturing techniques and to find cost reduction methods without compromising functional performance. In addition, alternative inks need to be formulated to increase the variety of functional inks and to pioneer new product developments. In this report, we investigate a thermoplastic-based nickel ink prototype to print electrodes using a screen-printing process. Process fundamentals are explored, and cost reduction methods are addressed by studying …


Global Packaging Trends, Bekir Keskin, Bilge N. Altay, Merve Akyol, Guven Meral, Olgun Uyar, Paul D. Fleming Oct 2018

Global Packaging Trends, Bekir Keskin, Bilge N. Altay, Merve Akyol, Guven Meral, Olgun Uyar, Paul D. Fleming

Bilge Nazli Altay

The packaging sector is one of the massive traditional fields in the printing industry. The rapid developments in technology and environmental regulations have been affecting the expectations from packaging. User demands and the concerns to protect the environment are the two main factors that now demanding change in material properties. The choice used to depend on the physical and chemical requirements of the products, although today’s global mind set on the concepts such as biodegradability, recyclability, reusability, sustainability and carbon footprint reduction are becoming the reason to tailor packaging properties. In general, the choices have been switching from petroleum to …


The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco Oct 2018

The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco

Buenaventura "Ven" Basco

No abstract provided.


Nickel Based Printed Resistance Temperature Detector On Flexible Polyimide Substrate, Vikram S. Turkani, Binu B. Narakatku, Dinesh Maddipatla, Bilge N. Altay, Paul D. Fleming, Bradley J. Bazuin, Massood Atashbar Dec 2017

Nickel Based Printed Resistance Temperature Detector On Flexible Polyimide Substrate, Vikram S. Turkani, Binu B. Narakatku, Dinesh Maddipatla, Bilge N. Altay, Paul D. Fleming, Bradley J. Bazuin, Massood Atashbar

Bilge Nazli Altay

A fully printed nickel (Ni) based resistance temperature detector (RTD) was successfully developed for temperature sensing applications in the automobile, agricultural and consumer electronic industries. The RTD was fabricated by
depositing nickel (Ni) ink on a flexible polyimide (PI) substrate using screen printing process. The capability of the printed RTD was demonstrated by measuring its resistive response for temperatures varying from -60 °C to 180 °C, in steps of 20 °C and its sensing characteristics such as linearity, sensitivity and repeatability were analyzed. The printed RTD demonstrated a linear response with resistive changes as high as 109% at 180 °C, …


Analysis Of Corrosion-Induced Diffusion Layer In Zk60a Magnesium Alloy.Pdf, Shumin Li Oct 2016

Analysis Of Corrosion-Induced Diffusion Layer In Zk60a Magnesium Alloy.Pdf, Shumin Li

Shumin Li

Corrosion-induced damage in ZK60A magnesium alloy is analyzed via chemo-mechanical tests. A certain “diffusion” corrosion layer (DCL) is identified, where partial corrosion takes place. This layer is different from the corrosion product layer (CPL). Nanoindentation analysis shows that corrosion modifies mechanical properties in the DCL, which extends up to 8–9 micrometers into the bulk, away from the CPL. Measurements over the DCL indicate a lower elastic modulus and lower fracture toughness compared with the bulk, as well as higher variance (heterogeneity). Elemental analysis confirms the layer is composed of partially oxidized magnesium and diffused chloride ions. Gradual changes in mechanical …


Smart Ink For Flexo - 2, Bilge N. Altay Dec 2015

Smart Ink For Flexo - 2, Bilge N. Altay

Bilge Nazli Altay

No abstract provided.


Under Sleeper Pads: Field Investigation Of Their Role In Detrimental Impact Mitigation, Sakdirat Kaewunruen, Alex M. Remennikov Jun 2015

Under Sleeper Pads: Field Investigation Of Their Role In Detrimental Impact Mitigation, Sakdirat Kaewunruen, Alex M. Remennikov

Sakdirat Kaewunruen

Under sleeper pads (USPs) are the component installed under the concrete sleepers generally to improve railway track resilience. Initial development in Europe, particularly in Austria, has encouraged the adoption of the component around the world. In practice, the component has commonly been used in certain applications, mainly to moderate track stiffness in special locations such as turnouts, crossings, and level crossing. In heavy haul operation, the heavier wagons result in sturdier bogie structures, higher unsprung mass, and then higher level of wheel-rail interaction forces. Accordingly, the application of USPs to mitigate detrimental impact load consequence on track structure is presented …


Thermal Vs. Photonic Sintering Of Nano Silver Based Conductive Inks, Bilge N. Altay, Paul D. Fleming May 2015

Thermal Vs. Photonic Sintering Of Nano Silver Based Conductive Inks, Bilge N. Altay, Paul D. Fleming

Bilge Nazli Altay

Conductive ink formulations with different electrical properties and their sintering methods after printing are an emerging area of interest. In this work, different line width and resolutions were printed on a a flexible PET substrate using a nano silver based conductive ink with gravure printing. Then printed traces were sintered with two different sintering methods and the results were compared.


Effects Of Temperature Change On Interfacial Delamination In Thermal Barrier Coatings, Hossein Ebrahimi, Soheil Nakhodchi Apr 2015

Effects Of Temperature Change On Interfacial Delamination In Thermal Barrier Coatings, Hossein Ebrahimi, Soheil Nakhodchi

Hossein Ebrahimi

No abstract provided.


Color And Texture Morphing With Colloids On Multilayered Surfaces.Pdf, Shumin Li Mar 2015

Color And Texture Morphing With Colloids On Multilayered Surfaces.Pdf, Shumin Li

Shumin Li

ABSTRACT: Dynamic morphing of marine species to match with environment
changes in color and texture is an advanced means for surviving, self-defense, and
reproduction. Here we use colloids that are placed inside a multilayered structure to
demonstrate color and texture morphing. The multilayer is composed of a thermal
insulating base layer, a light absorbing mid layer, and a liquid top layer. When external
light of moderate intensity (∼0.2 W cm−2) strikes the structure, colloids inside the
liquid layer will be assembled to locations with an optimal absorption. When this
system is exposed to continuous laser pulses, more than 18 000 …


Single-Layer Graphene Oxide Reinforced Metal Matrix Composites By Laser Sintering: Microstructure And Mechanical Property Enhancement, Dong Lin Oct 2014

Single-Layer Graphene Oxide Reinforced Metal Matrix Composites By Laser Sintering: Microstructure And Mechanical Property Enhancement, Dong Lin

dong lin

No abstract provided.


Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang Jul 2014

Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang

AZMAN ISMAIL

The external surface hardness of friction stir welded aluminum alloy 6063 pipe joint was investigated in this paper. The 89mm of outside diameter pipe with 5mm of wall thickness was used as test pipe piece for this experiment on closed butt joint configuration by utilising Bridgeport 2216 CNC milling machine and orbital clamping unit specially designed to cater for this task and function. Several welded samples were produced on varying process parameters which were successfully joined by using a non-consumable tool with a flat shoulder and a cylindrical pin.


Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang Jul 2014

Surface Hardness Of Friction Stir Welded Aa6063 Pipe, Azman Ismail, Mokhtar Awang

Azman Ismail

The external surface hardness of friction stir welded aluminum alloy 6063 pipe joint was investigated in this paper. The 89mm of outside diameter pipe with 5mm of wall thickness was used as test pipe piece for this experiment on closed butt joint configuration by utilising Bridgeport 2216 CNC milling machine and orbital clamping unit specially designed to cater for this task and function. Several welded samples were produced on varying process parameters which were successfully joined by using a non-consumable tool with a flat shoulder and a cylindrical pin.


Think Outside The Box: New Materials, Design Application, And Performance Of Railway Turnout Bearers, Sakdirat Kaewunruen May 2014

Think Outside The Box: New Materials, Design Application, And Performance Of Railway Turnout Bearers, Sakdirat Kaewunruen

Sakdirat Kaewunruen

Railway turnout systems are a main feature in railway tracks. There are two types of turnout support structures, which can be designed to be either a slab or a cluster of discrete bearers. The choice of turnout support system depends on asset management strategy of the rail operators or maintainers. This paper will focus on the discrete turnout bearer system where turnout alignments, settlement and deformation are comparatively more flexible and retrievable by routine ballast tamping. It embraces the consideration of new materials for use as a turnout bearer. Traditional bearer materials are timber, steel, and concrete. Recent developments have …


Impact Damage On A Thin Glass Plate With A Thin Polycarbonate Backing, Wenke Hu, Yenan Wang, Jian Yu, Chian-Fong Yen, Florin Bobaru Nov 2013

Impact Damage On A Thin Glass Plate With A Thin Polycarbonate Backing, Wenke Hu, Yenan Wang, Jian Yu, Chian-Fong Yen, Florin Bobaru

Florin Bobaru Ph.D.

We present experimental and computational results for the impact of a spherical projectile on a thin glass plate with a thin polycarbonate backing plate, restrained in a metal frame, or in the absence of the frame. We analyze the dependence of the damage patterns in the glass plate on the increasing impact velocities, from 61 m/s to 200 m/s. Experimental results are compared with those from peridynamic simulations of a simplified model. The main fracture patterns observed experimentally are captured by the peridynamic model for each of the three projectile velocities tested. More accurate implementation of the actual boundary conditions …


Development Of A Novel Handheld Device For Active Compensation Of Physiological Tremor, Abhijit Saxena Jul 2013

Development Of A Novel Handheld Device For Active Compensation Of Physiological Tremor, Abhijit Saxena

Abhijit Saxena

In microsurgery, the human hand imposes certain limitations in accurately positioning the tip of a device such as scalpel. Any errors in the motion of the hand make microsurgical procedures difficult and involuntary motions such as hand tremors can make some procedures significantly difficult to perform. This is particularly true in the case of vitreoretinal microsurgery. The most familiar source of involuntary motion is physiological tremor. Real-time compensation of tremor is, therefore, necessary to assist surgeons to precisely position and manipulate the tool-tip to accurately perform a microsurgery. In this thesis, a novel handheld device (AID) is described for compensation …


Friction Stir Welding On Aluminum Alloy 6063 Pipe, Azman Ismail, Mokhtar Awang, Hasan Fawad, Kamal Ahmad Jul 2013

Friction Stir Welding On Aluminum Alloy 6063 Pipe, Azman Ismail, Mokhtar Awang, Hasan Fawad, Kamal Ahmad

Azman Ismail

For Friction Stir Welding (FSW) process, a substantial amount of research done on aluminium plate but very few are found for aluminium pipe due to its tubular shape. A specially customised Orbital Clamping Unit (OCU) was used and fixed on the Bridgeport 2216 CNC milling machine in order to run the FSW on aluminium alloy 6063 pipe butt joint at several welding parameters. This OCU will hold these pipes together tightly, rotate these pipes at the required constant low speed, and ensure easy removal of pipe after the welding process before proceeding for further testing. This paper will study the …


Peridynamic Model For Dynamic Fracture In Unidirectional Fiber-Reinforced Composites, Wenke Hu, Youn Doh Ha, Florin Bobaru Jul 2013

Peridynamic Model For Dynamic Fracture In Unidirectional Fiber-Reinforced Composites, Wenke Hu, Youn Doh Ha, Florin Bobaru

Florin Bobaru Ph.D.

We propose a computational method for a homogenized peridynamics description of fiber-reinforced composites and we use it to simulate dynamic brittle fracture and damage in these materials. With this model we analyze the dynamic effects induced by different types of dynamic loading on the fracture and damage behavior of unidirectional fiber-reinforced composites. In contrast to the results expected from quasi-static loading, the simulations show that dynamic conditions can lead to co-existence of and transitions between fracture modes; matrix shattering can happen before a splitting crack propagates. We observe matrix–fiber splitting fracture, matrix cracking, and crack migration in the matrix, including …


Influence Of Van Der Waals Forces On Increasing The Strength And Toughness In Dynamic Fracture Of Nanofibre Networks: A Peridynamic Approach, Florin Bobaru Ph.D. Jul 2013

Influence Of Van Der Waals Forces On Increasing The Strength And Toughness In Dynamic Fracture Of Nanofibre Networks: A Peridynamic Approach, Florin Bobaru Ph.D.

Florin Bobaru Ph.D.

The peridynamic method is used here to analyse the effect of van der Waals forces on the mechanical behaviour and strength and toughness properties of three-dimensional nanofibre networks under imposed stretch deformation. The peridynamic formulation allows for a natural inclusion of long-range forces (such as van der Waals forces) by considering all interactions as ‘long-range’. We use van der Waals interactions only between different fibres and do not need to model individual atoms. Fracture is introduced at the microstructural (peridynamic bond) level for the microelastic type bonds, while van der Waals bonds can reform at any time. We conduct statistical …


Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha Ph.D., Florin Bobaru Ph.D. Jul 2013

Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha Ph.D., Florin Bobaru Ph.D.

Florin Bobaru Ph.D.

In this paper we discuss the peridynamic analysis of dynamic crack branching in brittle materials and show results of convergence studies under uniform grid refinement (m-convergence) and under decreasing the peridynamic horizon (δ-convergence). Comparisons with experimentally obtained values are made for the crack-tip propagation speed with three different peridynamic horizons.We also analyze the influence of the particular shape of themicro-modulus function and of different materials (Duran 50 glass and soda-lime glass) on the crack propagation behavior. We show that the peridynamic solution for this problem captures all the main features, observed experimentally, of dynamic crack propagation and branching, as well …


Travelling In Cuba, Fathi Habashi Feb 2013

Travelling In Cuba, Fathi Habashi

Fathi Habashi

Contact with Cuban scientists was established in 1986 when two researchers from Centro de Investigaciones para Industria Minero Metalurgica in Havana visited Laval University to get acquainted with research activities in the area of extractive metallurgy. This was followed in early 1987 by two more researchers from the same centre. Invitations were then received in late 1987, 1989, and 2008 to visit the nickel refineries in Cuba and to hold seminars at the University of Havana. The present report outlines these activities.


Voltage Tuning Of Ferromagnetic Resonance With Bistable Magnetization Switching In Energy-Efficient Magnetoelectric Composites, Ming Liu, Ziyao Zhou, Tianxiang Nan Dec 2012

Voltage Tuning Of Ferromagnetic Resonance With Bistable Magnetization Switching In Energy-Efficient Magnetoelectric Composites, Ming Liu, Ziyao Zhou, Tianxiang Nan

Tianxiang Nan

No abstract provided.


Experimental Verification Of The Linear Relationship Between Stress And The Reciprocal Of The Peak Barkhausen Voltage In Astm A36 Steel, Orfeas Kypris, Ikenna Nlebedim, David Jiles Jan 2012

Experimental Verification Of The Linear Relationship Between Stress And The Reciprocal Of The Peak Barkhausen Voltage In Astm A36 Steel, Orfeas Kypris, Ikenna Nlebedim, David Jiles

Orfeas Kypris

This study presents an experimental validation of a model theory for determining the relationship between a nondestructive measurement parameter and a property of interest. It was found that the reciprocal of the peak envelope amplitude of the Barkhausen emission voltage follows a linear relationship with stress. A linear relationship between stress and the reciprocal of the root mean square voltage was also obtained. These observations represent an important step towards improving the use of Barkhausen signals for magnetic non-destructive evaluation of stress as a function of depth in ferromagnetic load bearing structures.


Conceptual Design For Treatment Of Mining And Metallurgical Wastewaters Which Contains Arsenic And Antimony, Zeljko J. Kamberovic Jan 2012

Conceptual Design For Treatment Of Mining And Metallurgical Wastewaters Which Contains Arsenic And Antimony, Zeljko J. Kamberovic

Zeljko J Kamberovic

This paper presents a preliminary design for treatment of mining and metallurgical wastewaters (MMW) from the basin of antimony “Zajača“, which contains high concentrations of arsenic and antimony. MMW have been investigated in laboratory, due to large difference in concentrations of pollutants. Metallurgical wastewaters were treated using iron (II)-sulfate and lime milk used to adjust the pH value at 7. After chemical treatment of metallurgical wastewater and its joining with mining wastewater, residual amount of arsenic in water was below maximum allowed concentrations, while the concentration of antimony, remained above the maximum allowed value. The final phase of purification process …


Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi Jan 2012

Pyrite. History, Chemistry, And Metallurgy, Fathi Habashi

Fathi Habashi

The Book covers the history of pyrite - - how it was a strategic mineral necessary for the production of elemental sulfur needed for making gunpowder for military purposes and for the production of SO2 needed for making sulfuric acid for the chemical industry. Now its presence is a nuisance in tailings ponds. The book also covers the processing of pyrite containing gold, its chemistry and technology, the processing of pyrite cinder for the production of a variety of metals, and its behaviour towards autotrophic microorganisms.


Extractive Metallurgy Of Copper, Fathi Habashi Dec 2011

Extractive Metallurgy Of Copper, Fathi Habashi

Fathi Habashi

A short account on the extractive metallurgy of copper in 410 pages, fully illustrated in colour. It covers its chemistry, history, pyro-, hydro-, and electrometallurgy. Kinetics of leaching of copper ores and a literature guide are also included.