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Full-Text Articles in Engineering

Dynamic Magneto-Optical Imaging Of Superconducting Thin Films, Frederick Wells, Alexey V. Pan, Stephen Wilson, Igor Golovchanskiy, Sergey Fedoseev, Anatoly B. Rosenfeld Jan 2016

Dynamic Magneto-Optical Imaging Of Superconducting Thin Films, Frederick Wells, Alexey V. Pan, Stephen Wilson, Igor Golovchanskiy, Sergey Fedoseev, Anatoly B. Rosenfeld

Australian Institute for Innovative Materials - Papers

We present a novel method for analysis of superconducting thin films using dynamic magneto-optical imaging, revealing hallmarks of flux penetration with temporal resolution around 1 ms (in the present work) or better. This method involves investigation of transient field and dynamic current distributions, which are calculated by an inversion procedure on the Biot-Savart Law, which we show to be valid under dynamic conditions. We compare and discuss the flux front penetration speed and evolution of current distribution in high quality YBa2Cu3O${}_{7-\delta }$ thin films with that of samples deliberately damaged in such a way as to reduce critical current density …


Tuning Superconductivity In Fese Thin Films Via Magnesium Doping, Wenbin Qiu, Zongqing Ma, Yongchang Liu, Md Shahriar Hossain, Xiaolin Wang, Chuanbing Cai, S X. Dou Jan 2016

Tuning Superconductivity In Fese Thin Films Via Magnesium Doping, Wenbin Qiu, Zongqing Ma, Yongchang Liu, Md Shahriar Hossain, Xiaolin Wang, Chuanbing Cai, S X. Dou

Australian Institute for Innovative Materials - Papers

In contrast to its bulk crystal, the FeSe thin film or layer exhibits better superconductivity performance, which recently attracted much interest in its fundamental research as well as in potential applications around the world. In the present work, tuning superconductivity in FeSe thin films was achieved by magnesium-doping technique. Tc is significantly enhanced from 10.7 K in pure FeSe films to 13.4 K in optimized Mg-doped ones, which is approximately 1.5 times higher than that of bulk crystals. This is the first time achieving the enhancement of superconducting transition temperature in FeSe thin films with practical thickness (120 nm) via …


An Experimental And Numerical Investigation On Micro Rolling For Ultra-Thin Strip, Haibo Xie, Kenichi Manabe, Tsuyoshi Furushima, Kazuo Tada, Zhengyi Jiang Jan 2016

An Experimental And Numerical Investigation On Micro Rolling For Ultra-Thin Strip, Haibo Xie, Kenichi Manabe, Tsuyoshi Furushima, Kazuo Tada, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

The demand for miniaturized parts and miniaturized semi-finished products is increasing nowadays, because microforming processes can improve production rate and minimize material waste due to less forming passes. However, traditional macro metal forming processes and modelling cannot be simply scaled down to produce miniaturized micro parts. In this study, a 2-Hi micro rolling mill has been successfully built. Experimental and numerical investigations on the micro rolling process for ultra-thin SUS 304 stainless steel strip have been conducted. The experimental results show that the micro rolling deformation of ultra-thin strip is influenced by size effect which results from the specimen size …


Stress In Thin Wall Structures Made By Layer Additive Manufacturing, Vladimir Luzin, Nicholas P. Hoye Jan 2016

Stress In Thin Wall Structures Made By Layer Additive Manufacturing, Vladimir Luzin, Nicholas P. Hoye

Faculty of Engineering and Information Sciences - Papers: Part A

Manufacturing of thin wall structures is one of the main applications of additive manufacturing, where it has significant advantages over traditional milling and machining techniques or welded analogues. Such thin walled structures are common in structural aerospace components, and are also frequently made from titanium alloys. For such large-scale components, layer deposition strategy is more advantageous rather than a pixel-wise deposition approach due to the demand for high productivity and size requirements. Several techniques can be used to produce layer-wise build-ups, including laser-powered Direct Metal Deposition (DMD) process or gas tungsten arc welding (GTAW). Although, in the general case of …


Strain-Induced Magnetic Phase Transition In Srcoo3−Δ Thin Films, S J. Callori, S Hu, Joel Bertinshaw, Zhilian Yue, S Danilkin, Xiaolin Wang, V Nagarajan, Frank Klose, Jan Seidel, Clemens Ulrich Jan 2015

Strain-Induced Magnetic Phase Transition In Srcoo3−Δ Thin Films, S J. Callori, S Hu, Joel Bertinshaw, Zhilian Yue, S Danilkin, Xiaolin Wang, V Nagarajan, Frank Klose, Jan Seidel, Clemens Ulrich

Australian Institute for Innovative Materials - Papers

It has been well established that both in bulk at ambient pressure and for films under modest strains, cubic SrCoO3−δ (δ<0.2) is a ferromagnetic metal. Recent theoretical work, however, indicates that a magnetic phase transition to an antiferromagnetic structure could occur under large strain accompanied by a metal-insulator transition. We have observed a strain-induced ferromagnetic-to-antiferromagnetic phase transition in SrCoO3−δ films grown on DyScO3 substrates, which provide a large tensile epitaxial strain, as compared to ferromagnetic films under lower tensile strain on SrTiO3 substrates. Magnetometry results demonstrate the existence of antiferromagnetic spin correlations and neutron diffraction experiments provide a direct evidence for a G-type antiferromagnetic structure with Neél temperatures between TN∼135±10K and ∼325±10K, depending on the oxygen content of the samples. Therefore, our data experimentally confirm the predicted strain-induced magnetic phase transition to an antiferromagnetic state for SrCoO3−δ thin films under large epitaxial strain.


Ferroelectric And Magnetic Properties Of Aurivillius Bim+1ti3fem−3o3m+3 Thin Films, Tingting Jia, Hideo Kimura, Zhenxiang Cheng, Hongyang Zhao Jan 2015

Ferroelectric And Magnetic Properties Of Aurivillius Bim+1ti3fem−3o3m+3 Thin Films, Tingting Jia, Hideo Kimura, Zhenxiang Cheng, Hongyang Zhao

Australian Institute for Innovative Materials - Papers

Aurivillius Bim+1Ti3Fem−3O3m+3 (m = 4, 5, 6) thin films have been deposited by a pulsed laser deposition system. The x-ray diffraction patterns indicate the formation of orthorhombic phase. The remanent polarization (2Pr) of Bim+1Ti3Fem−3O3m+3 thin films is decreased with the m-number. Positive-up-negative-down measurements indicate the presence of ferroelectric (FE) polarization in as-obtained thin films. Piezoresponse force microscopy investigations confirm the existence of FE domains and the switchable polarization. Weak magnetic moment is detected in the Aurivillius films at room temperature. The present work …


Protein Nanorings Organized By Poly(Styrene-Block-Ethylene Oxide) Self-Assembled Thin Films, Jenny Malmström, Akshita Wason, Fergus Roache, N. Amy Yewdall, Mazdak Radjainia, Shanghai Wei, Michael J. Higgins, David Williams, Juliet A. Gerrard, Jadranka Travas-Sejdic Jan 2015

Protein Nanorings Organized By Poly(Styrene-Block-Ethylene Oxide) Self-Assembled Thin Films, Jenny Malmström, Akshita Wason, Fergus Roache, N. Amy Yewdall, Mazdak Radjainia, Shanghai Wei, Michael J. Higgins, David Williams, Juliet A. Gerrard, Jadranka Travas-Sejdic

Australian Institute for Innovative Materials - Papers

This study explores the use of block copolymer self-assembly to organize Lsmα, a protein which forms stable doughnut-shaped heptameric structures. Here, we have explored the idea that 2-D crystalline arrays of protein filaments can be prepared by stacking doughnut shaped Lsmα protein into the poly(ethylene oxide) blocks of a hexagonal microphase-separated polystyrene-b-polyethylene oxide (PS-b-PEO) block copolymer. We were able to demonstrate the coordinated assembly of such a complex hierarchical nanostructure. The key to success was the choice of solvent systems and protein functionalization that achieved sufficient compatibility whilst still promoting assembly. Unambiguous characterisation of these structures is difficult; however AFM …


Thin Silicon Strip Detectors For Beam Monitoring In Micro-Beam Radiation Therapy, Marco Povoli, Enver Alagoz, Alberto Bravin, Iwan Cornelius, E Bräuer-Krisch, Pauline Fournier, Thor E. Hansen, Angela Kok, Michael L. F Lerch, E Monakhov, J Morse, Marco Petasecca, Herwig Requardt, Anatoly B. Rosenfeld, D Röhrich, H Sandaker, M Salome, B Stugu Jan 2015

Thin Silicon Strip Detectors For Beam Monitoring In Micro-Beam Radiation Therapy, Marco Povoli, Enver Alagoz, Alberto Bravin, Iwan Cornelius, E Bräuer-Krisch, Pauline Fournier, Thor E. Hansen, Angela Kok, Michael L. F Lerch, E Monakhov, J Morse, Marco Petasecca, Herwig Requardt, Anatoly B. Rosenfeld, D Röhrich, H Sandaker, M Salome, B Stugu

Faculty of Engineering and Information Sciences - Papers: Part A

Microbeam Radiation Therapy (MRT) is an emerging cancer treatment that is currently being developed at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France. This technique uses a highly collimated and fractionated X-ray beam array with extremely high dose rate and very small divergence, to benefit from the dose-volume effect, thus sparing healthy tissue. In case of any beam anomalies and system malfunctions, special safety measures must be installed, such as an emergency safety shutter that requires continuous monitoring of the beam intensity profile. Within the 3DMiMic project, a novel silicon strip detector that can tackle the special features of …


A Practical Path Planning Methodology For Wire And Arc Additive Manufacturing Of Thin-Walled Structures, Donghong Ding, Zengxi Pan, Dominic Cuiuri, Huijun Li Jan 2015

A Practical Path Planning Methodology For Wire And Arc Additive Manufacturing Of Thin-Walled Structures, Donghong Ding, Zengxi Pan, Dominic Cuiuri, Huijun Li

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents a novel methodology to generate deposition paths for wire and arc additive manufacturing (WAAM). The medial axis transformation (MAT), which represents the skeleton of a given geometry, is firstly extracted to understand the geometry. Then a deposition path that is based on the MAT is efficiently generated. The resulting MAT-based path is able to entirely fill any given cross-sectional geometry without gaps. With the variation of step-over distance, material efficiency alters accordingly for both solid and thin-walled structures. It is found that thin-walled structures are more sensitive to step-over distance in terms of material efficiency. The optimal …


Micro Sheet Hydroforming Process Of Ultra-Thin Pure Titanium Foil, Hideki Sato, Kenichi Manabe, Dongbin Wei, Zhengyi Jiang, Daiki Kondo Jan 2015

Micro Sheet Hydroforming Process Of Ultra-Thin Pure Titanium Foil, Hideki Sato, Kenichi Manabe, Dongbin Wei, Zhengyi Jiang, Daiki Kondo

Faculty of Engineering and Information Sciences - Papers: Part A

A micro hydromechanical deep drawing is carried out using the pure titanium and the effect of fluid pressure on formability of pure titanium is investigated. The experiments are performed using the two kinds of pure titanium foils (TR270C-H and TR270C-O) and stainless steel foil (SUS304-H) with 50 thickness and the cylindrical and conical punches. As a result, it is found that the peeling off the oxide film of pure titanium can be reduced by applying the fluid pressure because the friction force and contact pressure between the blank and die decreases. However, the formability is lower for pure titanium than …


The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore Jan 2015

The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of Nb on the hardenability of ultra-thin cast strip (UCS) steels produced via the unique regime of rapid solidification, large austenite grain size, and inclusion engineering of the CASTRIP© process was investigated. Continuous cooling transformation (CCT) diagrams were constructed for 0, 0.014, 0.024, 0.04, 0.06 and 0.08 wt% Nb containing UCS steels. Phase nomenclature for the identification of lower transformation product in low carbon steels was reviewed. Even a small addition of 0.014 wt% Nb showed a potent effect on hardenability, shifting the ferrite C-curve to the right and expanding the bainitic ferrite and acicular ferrite phase …


Thin Film Lubrication Of Hexadecane Confined By Iron And Iron Oxide Surfaces: A Crucial Role Of Surface Structure, Thi Dinh Ta, A Kiet Tieu, Hongtao Zhu, Buyung Kosasih Jan 2015

Thin Film Lubrication Of Hexadecane Confined By Iron And Iron Oxide Surfaces: A Crucial Role Of Surface Structure, Thi Dinh Ta, A Kiet Tieu, Hongtao Zhu, Buyung Kosasih

Faculty of Engineering and Information Sciences - Papers: Part A

A comparative analysis of thin film lubrication of hexadecane between different iron and its oxide surfaces has been carried out using classical molecular dynamic simulation. An ab initio force-field, COMPASS, was applied for n-hexadecane using explicit atom model. An effective potential derived from density functional theory calculation was utilized for the interfacial interaction between hexadecane and the tribo-surfaces. A quantitative surface parameterization was introduced to investigate the influence of surface properties on the structure, rheological properties, and tribological performance of the lubricant. The results show that although the wall-fluid attraction of hexadecane on pure iron surfaces is significantly stronger than …


An Investigation Of The Nanomechanical Properties Of 0.5ba(Ti0.8zr0.2)O3-0.5(Ba0.7ca0.3)Tio3 Thin Films, Zhong-Lan Cai, Zeng-Mei Wang, Huan-Huan Wang, Zhenxiang Cheng, Baowen Li, Xin-Li Guo, Hideo Kimura, Akira Kasahara Jan 2015

An Investigation Of The Nanomechanical Properties Of 0.5ba(Ti0.8zr0.2)O3-0.5(Ba0.7ca0.3)Tio3 Thin Films, Zhong-Lan Cai, Zeng-Mei Wang, Huan-Huan Wang, Zhenxiang Cheng, Baowen Li, Xin-Li Guo, Hideo Kimura, Akira Kasahara

Australian Institute for Innovative Materials - Papers

For practical application, the functional piezoelectric film in microelectromechanical systems should meet the requirement of physical properties, as well as the mechanical properties. In this article, 0.5Ba(Ti0.8Zr0.2)O3-0.5(Ba0.7Ca0.3)TiO3 (0.5BZT-0.5BCT) thin films with varied properties were prepared on (100) Si substrates via a sol-gel technique at different annealing temperatures. The effects of the annealing temperature on the morphology, piezoelectricity, hardness, and elastic modulus were studied. Particular attention was paid to the surface frictional behavior of films, and the changes in the friction force can be radically explained in terms of differences in the hardness/elastic modulus ratio and the residual stress of films. …


Analysis Of Low-Field Isotropic Vortex Glass Containing Vortex Groups In Yba2cu3o7−X Thin Films Visualized By Scanning Squid Microscopy, Frederick Wells, Alexey V. Pan, Renshaw Wang, Sergey Fedoseev, Hans Hilgenkamp Jan 2015

Analysis Of Low-Field Isotropic Vortex Glass Containing Vortex Groups In Yba2cu3o7−X Thin Films Visualized By Scanning Squid Microscopy, Frederick Wells, Alexey V. Pan, Renshaw Wang, Sergey Fedoseev, Hans Hilgenkamp

Australian Institute for Innovative Materials - Papers

The glass-like vortex distribution in pulsed laser deposited YBa2Cu3O7 − x thin films is observed by scanning superconducting quantum interference device microscopy and analysed for ordering after cooling in magnetic fields significantly smaller than the Earth's field. Autocorrelation calculations on this distribution show a weak short-range positional order, while Delaunay triangulation shows a near-complete lack of orientational order. The distribution of these vortices is finally characterised as an isotropic vortex glass. Abnormally closely spaced groups of vortices, which are statistically unlikely to occur, are observed above a threshold magnetic field. The origin of these groups …


Ultrafast Spin Polarization In A Multiferroic Manganite Bife0.5mn0.5o3 Thin Film, Zeyu Zhang, Zuanming Jin, Xian Lin, Zhenxiang Cheng, H Y. Zhao, Hideo Kimura, Guohong Ma Jan 2015

Ultrafast Spin Polarization In A Multiferroic Manganite Bife0.5mn0.5o3 Thin Film, Zeyu Zhang, Zuanming Jin, Xian Lin, Zhenxiang Cheng, H Y. Zhao, Hideo Kimura, Guohong Ma

Australian Institute for Innovative Materials - Papers

In this work, we present observations of ultrafast carrier dynamics and spin polarization in a multiferroic manganite BiFe0.5Mn0.5O3 film excited by linearly and circularly polarized femtosecond pulses, respectively. The d-band charge transfer transition is reasonably assigned to Γ3 → Γ5. The transient reflectivity decay on a time scale as fast as only 0.3 ps is consistent with the picture of ultrafast electron-phonon coupling. The ultrafast switching of polarization ellipticity (< 150 fs) originates from a transient coherent spin polarization by optical orientation. The ultrafast spin polarization switching is assigned to the Raman coherence process.


Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou Jan 2015

Pauli-Limited Effect In The Magnetic Phase Diagram Of Fesexte1−X Thin Films, Jincheng Zhuang, Zhen Li, Xun Xu, Li Wang, Wai Kong Yeoh, X Z. Xing, Zhixiang Shi, Xiaolin Wang, Yi Du, S X. Dou

Australian Institute for Innovative Materials - Papers

We present a detailed investigation on the doping dependence of the upper critical fieldHc2(T) of FeSexTe1−xthin films (0.18 ≤ x ≤ 0.90) by measuring the electrical resistivity as a function of magnetic field. The Hc2(T) curves exhibit a downturn behavior with decreasing temperature in all the samples, owing to the Pauli-limited effect (spin paramagnetic effect). The Pauli-limited effect on the upper critical field can be monotonically modulated by variation of the Se/Te composition. Our results show that Te-doping induced disorder and excess Fe atoms give rise to enhancement of the Pauli-limited effect.


In Situ Anchoring Uniform Mno2 Nanosheets On Three-Dimensional Macroporous Graphene Thin-Films For Supercapacitor Electrodes, Yong Zhao, Yuena Meng, Haiping Wu, Yue Wang, Zhixiang Wei, Xiaojun Li, Peng Jiang Jan 2015

In Situ Anchoring Uniform Mno2 Nanosheets On Three-Dimensional Macroporous Graphene Thin-Films For Supercapacitor Electrodes, Yong Zhao, Yuena Meng, Haiping Wu, Yue Wang, Zhixiang Wei, Xiaojun Li, Peng Jiang

Australian Institute for Innovative Materials - Papers

We present a facile and efficient fabrication of 3D macroporous rGO/MnO2 nanosheet thin-films for supercapacitor electrodes. An amorphous-carbon-modified rGO thin-film is firstly prepared through a simple glucose and CaCO3 particle mediated template method. Then ultrathin MnO2 nanosheets are in situ synthesized on the rGO networks by the rapid and scalable redox reaction between KMnO4 and amorphous carbon. The fabricated three-dimensional porous hybrid thin-film shows a high specific capacitance of 245 F g-1 (based on the total mass of the film) at a scan rate of 2 mV s-1, a good rate capability of 143 F g-1 at 300 mV s-1, …


Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt Jan 2015

Increased Upconversion Performance For Thin Film Solar Cells: A Trimolecular Composition, Yuen Yap Cheng, Andrew Nattestad, Tim F. Schulze, Rowan W. Macqueen, Burkhard Fückel, Klaus Lips, Gordon G. Wallace, Tony Khoury, Maxwell J. Crossley, Timothy W. Schmidt

Australian Institute for Innovative Materials - Papers

Photochemical upconversion based on triplet-triplet annihilation (TTA-UC) is employed to enhance the short-circuit currents generated by two varieties of thin-film solar cells, a hydrogenated amorphous silicon (a-Si:H) solar cell and a dye-sensitized solar cell (DSC). TTA-UC is exploited to harvest transmitted sub-bandgap photons, combine their energies and re-radiate upconverted photons back towards the solar cells. In the present study we employ a dual-emitter TTA-UC system which allows for significantly improved UC quantum yields as compared to the previously used single-emitter TTA systems. In doing so we achieve record photo-current enhancement values for both the a-Si:H device and the DSC, surpassing …


Analysis Of Thin Strip Profile By Work Roll Crossing And Shifting In Asymmetrical Cold Rolling, Abdulrahman Aljabri, Zhengyi Jiang, Dongbin Wei Jan 2015

Analysis Of Thin Strip Profile By Work Roll Crossing And Shifting In Asymmetrical Cold Rolling, Abdulrahman Aljabri, Zhengyi Jiang, Dongbin Wei

Faculty of Engineering and Information Sciences - Papers: Part A

In order to analyze the effects of cold rolling parameters such as the crossing angle and axial shifting value of work rolls on the strip profile, extensive tests were carried out on a 4-high rolling mill equipped with a work roll crossing and shifting system. The results show that the strip profile is nearly flat under asymmetrical rolling. The rolling force was also analyzed in detail by changing the crossing angle and axial shifting value of work rolls.


Microscopic Model For Exchange Bias From Grain-Boundary Disorder In A Ferromagnet/Antiferromagnet Thin Film With A Nanocrystalline Microstructure, David L. Cortie, A G. Biternas, R W. Chantrell, Xiaolin Wang, Frank Klose Jan 2014

Microscopic Model For Exchange Bias From Grain-Boundary Disorder In A Ferromagnet/Antiferromagnet Thin Film With A Nanocrystalline Microstructure, David L. Cortie, A G. Biternas, R W. Chantrell, Xiaolin Wang, Frank Klose

Australian Institute for Innovative Materials - Papers

Monte Carlo spin simulations were coupled to a Voronoi microstructure-generator to predict the magnitude and behavior of exchange bias in a ferromagnet/antiferromagnet (AF) thin film bilayer with a nanocrystalline microstructure. Our model accounts for the effects of irregular grain-shapes, finite-sized particles, and the possible presence of local random-fields originating from the antiferromagnet's grain-boundary regions. As the grain-boundary represents a crystal-structure distortion, we model the local effect on the exchange constants in the Gaussian approximation which can cause regions resembling a spin glass confined to an unusual 2D topology. Although an ensemble of completely disconnected AF grains isolated by non-magnetic barriers …


Thin Strip Profile Control Capability Of Roll Crossing And Shifting In Cold Rolling Mill, Abdulrahman Aljabri, Zhengyi Jiang, Dongbin Wei, Xiaodong Wang, Hassan Tibar Jan 2014

Thin Strip Profile Control Capability Of Roll Crossing And Shifting In Cold Rolling Mill, Abdulrahman Aljabri, Zhengyi Jiang, Dongbin Wei, Xiaodong Wang, Hassan Tibar

Faculty of Engineering and Information Sciences - Papers: Part A

Controlling cold strip profile is a difficult and significant problem has been found in industry during thin strip rolling. At present choosing the new type of strip rolling mill is the one of main methods to control the strip shape quality in cold rolling. The influences of rolling process parameters such as the work roll cross angle and work roll shifting on the strip shape and profile of thin strip are recognised throughout this study. The results show that the roll crossing and shifting is efficient way to control the strip shape. The increase of the work roll crossing angle …


Shape Optimization Of Thin-Walled Steel Sections Using Graph Theory And Aco Algorithm, Pezhman Sharafi, Lip H. Teh, Muhammad N. S Hadi Jan 2014

Shape Optimization Of Thin-Walled Steel Sections Using Graph Theory And Aco Algorithm, Pezhman Sharafi, Lip H. Teh, Muhammad N. S Hadi

Faculty of Engineering and Information Sciences - Papers: Part A

This paper presents an intuitive procedure for the shape and sizing optimizations of open and closed thin-walled steel sections using the graph theory. The goal is to find shapes of optimum mass and strength (bi-objectives). The shape optimization of open sections is treated as a multi-objective all-pairs shortest path problem, while that of closed sections is treated as a multi-objective minimum mean cycle problem. The sizing optimization of a predetermined shape is treated as a multi-objective single-pair shortest path problem. Multi-colony ant algorithms are formulated for solving the optimization problems. The verification and numerical examples involving the shape optimizations of …


Large Piezoelectric Coefficient And Ferroelectric Nanodomain Switching In Ba(Ti0.80zr0.20)O3-0.5(Ba0.70ca 0.30)Tio3 Nanofibers And Thin Films, A Jalalian, A Grishin, Xiaolin Wang, Zhenxiang Cheng, S X. Dou Jan 2014

Large Piezoelectric Coefficient And Ferroelectric Nanodomain Switching In Ba(Ti0.80zr0.20)O3-0.5(Ba0.70ca 0.30)Tio3 Nanofibers And Thin Films, A Jalalian, A Grishin, Xiaolin Wang, Zhenxiang Cheng, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

Currently available low-dimensional piezoelectric materials show a low piezoelectric coefficient d33 of merely 100 pm V-1 with Pb(Zr, Ti)O3-based materials at the high end. Here, we report very large piezoelectricity in Ba(Ti0.80Zr0.20)O 3-0.5(Ba0.70Ca0.30)TiO3 (BTZ-0.5BCT) lead-free nanostructures sintered as thin films (d33 = 140 pm V -1) and nanofibers (d33 = 180 pm V-1). The influences of lateral size, geometry, and the clamping effect on the piezoelectric performance were investigated for both thin films and nanofibers. Combining a high piezoelectric coefficient with environmental benefits, the BTZ-0.5BCT nanostructures provide the superior functions sought for highly efficient piezoelectric devices and electromechanical systems. 2014 …


Thin, Tough, Ph-Sensitive Hydrogel Films With Rapid Load Recovery, Sina Naficy, Geoffrey M. Spinks, Gordon G. Wallace Jan 2014

Thin, Tough, Ph-Sensitive Hydrogel Films With Rapid Load Recovery, Sina Naficy, Geoffrey M. Spinks, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

Stimuli-responsive hydrogels are used as the building blocks of actuators and sensors. Their application has been limited, however, by their lack of mechanical strength and recovery from loading. Here, we report the preparation of pH-sensitive hydrogels as thin as 20 μm. The hydrogels are made of a polyether-based polyurethane and poly(acrylic acid). A simple method was employed to create hydrogels with thicknesses in the range of 20-570 μm. The hydrogel films volume changed by a factor of ∼2 when the pH was switched around the transition point (pH 4). Tensile extensibilities of up to ∼350% were maintained at each pH, …


Highly Oriented Lifepo4 Thin Film Electrodes Via Chemical Solution Deposition, Qi Li, Shulei Chou, Jiazhao Wang, Dongqi Shi, Hua-Kun Liu Jan 2014

Highly Oriented Lifepo4 Thin Film Electrodes Via Chemical Solution Deposition, Qi Li, Shulei Chou, Jiazhao Wang, Dongqi Shi, Hua-Kun Liu

Australian Institute for Innovative Materials - Papers

Highly oriented LiFePO4 thin-film electrodes were fabricated via chemical solution deposition combined with spin coating. The effects of the precursor concentrations and types of substrates on microstructures and electrochemical performances were studied. Single-phase LiFePO4 with orientations perpendicular to the (211)/(020) and (311) planes prepared using stainless steel as substrate presents the capacity of 4.9 μAh•cm-2 and the apparent activation energy of 59.2 kJ•mol-1, indicating its great potential to be used as cathode material for lithium thin film batteries.


Pb Thin Films On Si(111): Local Density Of States And Defects, Stefan Eilers, Yi Du, S X. Dou Jan 2014

Pb Thin Films On Si(111): Local Density Of States And Defects, Stefan Eilers, Yi Du, S X. Dou

Australian Institute for Innovative Materials - Papers

Local density of states and atomic structure of the stripped incommensurate phase, the √3 x√7 phase and the 1 x 1 phase of a monolayer of Pb on Si(111) are characterized by scanning tunneling microscopy and spectroscopy. The dI/dV-images reveal congruent local density of states structures for the stripped incommensurate and the √3 x√ phase but suggest a hexagonal lattice of the local density of states for the 1x1 phase while the atomic structure consists of one more atom in the center of each hexagon. Vacancy defects and impurities show a depletion of local density of states for the stripped …


Biocompatible Ionic Liquid-Biopolymer Electrolyte Enabled Thin And Compact Magnesium Air Batteries, Xiaoteng Jia, Yang Yang, Caiyun Wang, Chen Zhao, R Vijayaraghavan, Douglas R. Macfarlane, Maria Forsyth, Gordon G. Wallace Jan 2014

Biocompatible Ionic Liquid-Biopolymer Electrolyte Enabled Thin And Compact Magnesium Air Batteries, Xiaoteng Jia, Yang Yang, Caiyun Wang, Chen Zhao, R Vijayaraghavan, Douglas R. Macfarlane, Maria Forsyth, Gordon G. Wallace

Australian Institute for Innovative Materials - Papers

With the surge of interest in miniaturized implanted medical devices (IMDs), implantable power sources with small dimensions and biocompatibility are in high demand. Implanted battery/supercapacitor devices are commonly packaged within a case that occupies a large volume, making miniaturization difficult. In this study, we demonstrate a polymer electrolyte-enabled biocompatible magnesium-air battery device with a total thickness of approximately 300 μm. It consists of a biocompatible polypyrrole-para(toluene sulfonic acid) cathode and a bioresorbable magnesium alloy anode. The biocompatible electrolyte used is made of choline nitrate (ionic liquid) embedded in a biopolymer, chitosan. This polymer electrolyte is mechanically robust and offers a …


Significant Tunability Of Thin Film Functionalities Enabled By Manipulating Magnetic And Structural Nano-Domains, Igor A. Golovchanskiy, Alexey V. Pan, Sergey A. Fedoseev, Michael Higgins Jan 2014

Significant Tunability Of Thin Film Functionalities Enabled By Manipulating Magnetic And Structural Nano-Domains, Igor A. Golovchanskiy, Alexey V. Pan, Sergey A. Fedoseev, Michael Higgins

Australian Institute for Innovative Materials - Papers

The influence of laser frequency on the structure and physical properties of thin films grown by pulsed laser deposition has been studied. Different types of thin films, hard ferromagnetic FePt L10 and quasi-single crystal superconducting YBa2Cu3O7 (YBCO), have been used for demonstration of the effect. Significant structural modifications have been obtained for the films with similar thicknesses. These modifications are shown to dramatically control their corresponding properties, providing an instrumental ability for tuning the practical characteristics of the films by changing the laser frequency of their deposition. In particular, 20-fold increase of coercive field and modification of demagnetization mechanism are …


Analysis Of Thin Strip Profile During Asymmetrical Cold Rolling With Roll Crossing And Shifting Mill, Abdulrahman Aljabri, Zhengyi Jiang, Dongbin Wei Jan 2014

Analysis Of Thin Strip Profile During Asymmetrical Cold Rolling With Roll Crossing And Shifting Mill, Abdulrahman Aljabri, Zhengyi Jiang, Dongbin Wei

Faculty of Engineering and Information Sciences - Papers: Part A

Strip profile control during rolling is required to assure the dimensional quality of rolled thin strip is acceptable for customers. Throughout rolling, the strip profile is controlled by using the advanced shape control rolling mill, such as the combination of work roll crossing and shifting during asymmetrical rolling, the one of the valuable methods to control the strip profile quality in rolling process. In this paper, the influences of cold rolling parameters such as the crossing angle and axial shifting value of work rolls on the strip profile are analysed. The strip shape control is discussed under both symmetrical and …


Correlation Between Structural Parameters And The Magnetocaloric Effect In Epitaxial La0.8ca0.2mno3/Laalo3 Thin Film, J C. Debnath, J H. Kim, Y Heo, A M. Strydom, S X. Dou Jan 2013

Correlation Between Structural Parameters And The Magnetocaloric Effect In Epitaxial La0.8ca0.2mno3/Laalo3 Thin Film, J C. Debnath, J H. Kim, Y Heo, A M. Strydom, S X. Dou

Australian Institute for Innovative Materials - Papers

An epitaxial La0.8Ca0.2MnO3/LaAlO 3 (LCMO/LAO) thin film was fabricated using the pulsed laser deposition technique to evaluate the correlation between the crystal structure and the magnetocaloric effect. In our study, the LCMO film was 200 nm in thickness and appeared to have a strong out-of plane texture. We found that each column in the LCMO thin film layer is a domain which has a different ordering direction. These microscopic feature results in anisotropic properties of magnetization, entropy, and relative cooling power. The film exhibited a paramagnetic-to-ferromagnetic second order phase transition at 249 K. The lack of any hysteresis loss also …