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Full-Text Articles in Engineering

Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou Oct 2013

Magnetic Properties And Magnetocaloric Effect Of Ndmn2−Xtixsi2 Compounds, M F. Md Din, Jianli Wang, S J. Campbell, R Zeng, W D. Hutchison, M Avdeev, S J. Kennedy, S X. Dou

Australian Institute for Innovative Materials - Papers

The structural and magnetic properties of the intermetallic compounds NdMn2−xTixSi2(x = 0, 0.1, 0.2, and 0.3) have been studied by x-ray and high resolution neutron powder diffraction, specific heat, dc magnetization, and differential scanning calorimetry measurements over the temperature range 3–450 K. The Curie temperature and Néel temperature of NdMn2Si2 decrease from TC = 36 K and TN = 380 K to TC = 14 K and TN = 360 K, respectively, on substitution of Ti (x = 0.3) for Mn. The magnetocaloric effect …


Effect Of Polymer Ligand Structures On Fluorescence Of Gold Clusters Prepared By Photoreduction, Luo Li, Zhen Li, Hui Zhang, Shoucun Zhang, Irfan Majeed, Bien Tan Jan 2013

Effect Of Polymer Ligand Structures On Fluorescence Of Gold Clusters Prepared By Photoreduction, Luo Li, Zhen Li, Hui Zhang, Shoucun Zhang, Irfan Majeed, Bien Tan

Australian Institute for Innovative Materials - Papers

Blue emission fluorescent Au5 clusters with maximum quantum yield of 20.1% were synthesized by a simple photoreduction method using three specially designed tridentate polymer ligands. The evolution of fluorescent Au nanoclusters (Au NCs) under UV irradiation was studied by fluorescence, UV-Vis and X-ray photoelectron spectroscopic techniques, suggesting that the fluorescence of Au NCs is size-dependent and is associated with the presence of Au(i) ions in the Au NCs. The effect of polymer structure on the fluorescent Au NCs has also been discussed. These highly fluorescent Au NCs have potential applications in the fabrication of optoelectronic devices and light emitting materials.


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 …


Effect Of Sintering Temperature On The Superconducting Properties Of Graphene Doped Mgb2, K S B De Silva, X Xu, Sanjeev Gambhir, D C K Wong, W X Li, Q Y. Hu Jan 2013

Effect Of Sintering Temperature On The Superconducting Properties Of Graphene Doped Mgb2, K S B De Silva, X Xu, Sanjeev Gambhir, D C K Wong, W X Li, Q Y. Hu

Australian Institute for Innovative Materials - Papers

A comprehensive study on the effects of sintering temperature on graphene-doped MgB2 superconductor was conducted. Graphene has emerged as an effective dopant that is capable of improving the critical current density (J-{\rm c}) and flux pinning at a very low doping level, with only a slight reduction of the critical temperature (T-{\rm c}). MgB2 undoped and graphene-doped bulk samples were prepared by the in situ method and sintered within a temperature range from 650 to 950 {\circ}\hbox{C}. It is surprising to note that at the doping level of 1 at.% the sample sintered at 850 {\circ}\hbox{C} shows a J\rm c …


The Effect Of Microscopic Texture On The Direct Plasma Surface Passivation Of Si Solar Cells, S Mehrabian, S Xu, A A. Qaemi, B Shokri, C Chan, K Ostrikov Jan 2013

The Effect Of Microscopic Texture On The Direct Plasma Surface Passivation Of Si Solar Cells, S Mehrabian, S Xu, A A. Qaemi, B Shokri, C Chan, K Ostrikov

Australian Institute for Innovative Materials - Papers

Textured silicon surfaces are widely used in manufacturing of solar cells due to increasing the light absorption probability and also the antireflection properties. However, these Si surfaces have a high density of surface defects that need to be passivated. In this study, the effect of the microscopic surface texture on the plasma surface passivation of solar cells is investigated. The movement of 105Hþ ions in the texture-modified plasma sheath is studied by Monte Carlo numerical simulation. The hydrogen ions are driven by the combined electric field of the plasma sheath and the textured surface. The ion dynamics is simulated, and …


Effect Of Eccentric Load On Retrofitted Reinforced Concrete Columns Confined With Frp, Thong M. Pham, X Lei, Muhammad N. S Hadi Jan 2013

Effect Of Eccentric Load On Retrofitted Reinforced Concrete Columns Confined With Frp, Thong M. Pham, X Lei, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

Different behaviour of diverse sections of confined Reinforced Concrete (RC) columns under eccentric load is investigated in this study. Three types of sections are considered, which include square columns, square with rounded corners and modified circular columns. Twelve reinforced square concrete columns were made from normal strength concrete and subdivided into four groups. The first three columns were the Reference Group and had no modification.The next three columnswere modified with round corners and wrapped with three layers of Carbon Fibre Reinforced Polymer (CFRP), another three were bonded with four pieces of segmental circular concrete covers and wrapped with three layers …


Effect Of Ply Configuration On Hollow Square Reinforced Concrete Columns Confined With Carbon Fibre-Reinforced Polymer (Cfrp), T D. Le, M T. Lester, Muhammad N. S Hadi Jan 2013

Effect Of Ply Configuration On Hollow Square Reinforced Concrete Columns Confined With Carbon Fibre-Reinforced Polymer (Cfrp), T D. Le, M T. Lester, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

This paper presents results of testing twelve hollow square reinforced concrete specimens wrapped with Carbon fibre reinforced polymer CFRP. The effect of ply configuration on the behaviour of the specimens is investigated. All specimens were 800mm high and had the dimensions of 200mm×200mm in cross-section and a hollow core of 80mm×80 mm. The specimens were divided into four groups with three specimens each. The specimens in the first group without bonding CFRP served as references. While the remaining three groups of specimens were externally wrapped with CFRP in three different ply configurations of hoop, vertical and 45◦ angle with reference …


The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou Jan 2013

The Magnetocaloric Effect And Critical Behaviour Of The Mn0.94ti0.06coge Alloy, P Shamba, Jianli Wang, J C. Debnath, S J. Kennedy, Rong Zeng, M F Md Din, F Hong, Z X. Cheng, A J. Studer, S X. Dou

Faculty of Engineering and Information Sciences - Papers: Part A

Structural, magnetic and magnetocaloric properties of the Mn0.94Ti0.06CoGe alloy have been investigated using x-ray diffraction, DC magnetization and neutron diffraction measurements. Two phase transitions have been detected, at T-str = 235 K and T-C = 270 K. A giant magnetocaloric effect has been obtained at around Tstr associated with a structural phase transition from the low temperature orthorhombic TiNiSi-type structure to the high temperature hexagonal Ni2In-type structure, which is confirmed by neutron study. In the vicinity of the structural transition, at T-str, the magnetic entropy change, -Delta S-M reached a maximum value of 14.8 J kg(-1) K-1 under a magnetic …


Effect Of Microstructure And Composition On Hydrogen Permeation In X70 Pipeline Steels, Ayesha J. Haq, K Muzaka, D P. Dunne, A Calka, E V. Pereloma Jan 2013

Effect Of Microstructure And Composition On Hydrogen Permeation In X70 Pipeline Steels, Ayesha J. Haq, K Muzaka, D P. Dunne, A Calka, E V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The influence of microstructure and composition on permeation of hydrogen in 1.2 and 0.5 wt.% Mn X70 pipeline steels after different processing was investigated using an electrochemical permeation technique. For 1.2 wt.% Mn (standard Mn) steel, the microstructure of normalised transfer bar was coarse equiaxed ferrite grains. This sample exhibited the highest diffusivity, followed by transfer bar, with a mixed ferriteebainitic ferrite microstructure; and hot rolled strip, with fine elongated ferrite grains. The 0.5 wt.% Mn (medium Mn) strip displayed lower diffusivity than the 1.2 wt.% Mn strip, due to hydrogen trapping by finer ferrite grains and a higher density …


A Random Effect Block Bootstrap For Clustered Data, Raymond L. Chambers, Hukum Chandra Jan 2013

A Random Effect Block Bootstrap For Clustered Data, Raymond L. Chambers, Hukum Chandra

Faculty of Engineering and Information Sciences - Papers: Part A

Random effects models for hierarchically dependent data, e.g. clustered data, are widely used. A popular bootstrap method for such data is the parametric bootstrap based on the same random effects model as that used in inference. However, it is hard to justify this type of bootstrap when this model is known to be an approximation. In this paper we describe a random effect block bootstrap approach for clustered data that is simple to implement, free of both the distribution and the dependence assumptions of the parametric bootstrap and is consistent when the mixed model assumptions are valid. Results based on …


The Effect Of Cooling Rates On The Microstructure And Mechanical Properties Of Thermo-Mechanically Processed Ti-Al-Mo-V-Cr-Fe Alloys, Mansur Ahmed, Dmytro G. Savvakin, Orest M. Ivasishin, Elena V. Pereloma Jan 2013

The Effect Of Cooling Rates On The Microstructure And Mechanical Properties Of Thermo-Mechanically Processed Ti-Al-Mo-V-Cr-Fe Alloys, Mansur Ahmed, Dmytro G. Savvakin, Orest M. Ivasishin, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

Two near-β titanium alloys, Ti–5Al–5Mo–5V–1Cr–1Fe and a modified one containing 2 wt% Cr (Ti–5Al–5Mo–5V–2Cr–1Fe) were produced from Ti hydride precursor powders via the cost-effective blended elemental powder metallurgy technique. The effects of two cooling rates (10 K s−1 and 1 K s−1) during thermo-mechanical processing on the microstructure and mechanical properties were investigated using X-ray diffraction and scanning electron microscopy. X-ray line profile analysis revealed that dislocation densities and microstrain in β-Ti phase are higher than in α-Ti phase for all cases. In both alloys, slower cooling results in an increase in α volume fraction and promotes morphology of continuous …


Effect Of Deformation Temperature On Niobium Clustering, Precipitation And Austenite Recrystallisation In A Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Alshahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma Jan 2013

Effect Of Deformation Temperature On Niobium Clustering, Precipitation And Austenite Recrystallisation In A Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Alshahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of deformation temperature on Nb solute clustering, precipitation and the kinetics of austenite recrystallisation were studied in a steel containing 0.081C–0.021Ti–0.064 Nb (wt%). Thermo-mechanical processing was carried out using a Gleeble 3500 simulator. The austenite microstructure was studied using a combination of optical microscopy, transmission electron microscopy, and atom probe microscopy, enabling a careful characterisation of grain size, as well as Nb-rich clustering and precipitation processes. A correlation between the austenite recrystallisation kinetics and the chemistry, size and number density of Nb-rich solute atom clusters, and NbTi(C,N) precipitates was established via the austenite deformation temperature. Specifically, we have …


Effect Of Austenitising And Deformation Temperatures On Dynamic Recrystallisation In Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Shahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma Jan 2013

Effect Of Austenitising And Deformation Temperatures On Dynamic Recrystallisation In Nb-Ti Microalloyed Steel, Andrii G. Kostryzhev, Abdullah Al Shahrani, Chen Zhu, Simon P. Ringer, Elena V. Pereloma

Faculty of Engineering and Information Sciences - Papers: Part A

An investigation into influence of the austenitising temperature and the austenite deformation temperature on Nb precipitation and recrystallisation kinetics was carried out for a steel containing 0.081C-0.021Ti-0.064Nb (wt. %). The austenite grain structure was correlated to the dispersive properties of Nb atom clustering and precipitation. Irrespective of the austenitising temperature, deformation to 0.75 strain at 1075 °C produced a fully recrystallised microstructure. After deformation at 975 °C, only partial recrystallisation was observed in the samples austenitised at higher temperature, whereas samples austenitised at lower temperature were fully recrystallised. The influence of solute drag and particle pinning effects on the recrystallisation …


Effect Of First Network Topology On The Toughness Of Double Network Hydrogels, Hai Xin, Sureyya Saricilar, Hugh Ralph Brown, Philip G. Whitten, Geoffrey Maxwell Spinks Jan 2013

Effect Of First Network Topology On The Toughness Of Double Network Hydrogels, Hai Xin, Sureyya Saricilar, Hugh Ralph Brown, Philip G. Whitten, Geoffrey Maxwell Spinks

Faculty of Engineering and Information Sciences - Papers: Part A

The fracture toughness of a double network (DN) hydrogel is shown here to be directly proportional to the toughness of the first-formed network. A series of DN gels was prepared in which the cross-link density of the first (tighter) network was controlled by varying the monomer and cross-linker concentrations. The toughness, tensile strength and elastic modulus of the DN gels increased significantly with an increase in the cross-link density of the first network and with identically prepared second networks. Moreover, the toughness of the double network was found to be linearly related to the toughness of the first network with …


Effect Of Particle Properties On The Discrete Element Simulation Of Wall Friction, Andrew Grima, Peter Wypych Jan 2013

Effect Of Particle Properties On The Discrete Element Simulation Of Wall Friction, Andrew Grima, Peter Wypych

Faculty of Engineering and Information Sciences - Papers: Part A

Modelling the interaction between particles and boundaries is of great interest and importance in many Discrete Element Method (DEM) applications where boundary failure conditions dictate the flow behaviour and velocity gradients of a bulk material. Bulk wall friction angles in DEM models are dependent on the mechanical properties of the particles and boundary material as well as the constraints of the contact models used, especially the tangential and rolling torque components. This paper examines the parameters determined from the calibration inclination test by conducting direct wall shear tests to validate the accuracy of the calibration parameters and the sensitivity of …


The Effect Of Chemical Composition On Microstructure And Properties Of Intercritically Reheated Coarse-Grained Heat-Affected Zone In X70 Steels, Zhixiong Zhu, Lenka Kuzmikova, Huijun Li, Frank J. Barbaro Jan 2013

The Effect Of Chemical Composition On Microstructure And Properties Of Intercritically Reheated Coarse-Grained Heat-Affected Zone In X70 Steels, Zhixiong Zhu, Lenka Kuzmikova, Huijun Li, Frank J. Barbaro

Faculty of Engineering and Information Sciences - Papers: Part A

The current study investigates the effect of different levels of Ti, N, and Ti/N ratios on microstructure and properties in the intercritically reheated coarse-grained heat-affected zone (ICCGHAZ) of two-pass submerged arc welds in API 5L grade X70 pipe. Gleeble simulation was employed to reproduce the ICCGHAZ of actual welds. Hardness and Charpy V-notch (CVN) tests were performed on the simulated samples. The microstructure of simulated ICCGHAZ was characterized by optical microscopy and scanning electron microscopy (SEM). LePera color etching technique was employed to identify and quantify the martensitic-austenitic (M-A) constituent. Results show that the simulated ICCGHAZ exhibited extremely low toughness, …


The Joint Effect Of Image Blur And Illumination Distortions For Mobile Visual Search Of Print Media, Yi Cao, Christian Ritz, Raad Raad Jan 2013

The Joint Effect Of Image Blur And Illumination Distortions For Mobile Visual Search Of Print Media, Yi Cao, Christian Ritz, Raad Raad

Faculty of Engineering and Information Sciences - Papers: Part A

Mobile Visual Search (MVS) is an emerging area of research given the explosion of smart and powerful mobile devices. Typically, the performance of MVS applications is influenced by the implemented image processing algorithms as well as various distortions that occur when capturing images by the mobile camera. This paper examines the joint effect of two common distortions, namely the illumination changes and image blurring on image matching accuracy for print media when using four state-of-the art local feature algorithms. Results obtained for a database of real camera images captured by two different camera models show that the illumination changes have …


Automatic Bdi Plan Recognition From Process Execution Logs And Effect Logs, Hongyun Xu, Bastin Tony Roy Savarimuthu, Aditya Ghose, Evan Morrison, Qiying Cao, Youqun Shi Jan 2013

Automatic Bdi Plan Recognition From Process Execution Logs And Effect Logs, Hongyun Xu, Bastin Tony Roy Savarimuthu, Aditya Ghose, Evan Morrison, Qiying Cao, Youqun Shi

Faculty of Engineering and Information Sciences - Papers: Part A

Agent applications are often viewed as unduly expensive to develop and maintain in commercial contexts. Organizations often settle for less sophisticated and more traditional software in place of agent technology because of (often misplaced) fears about the development and maintenance costs of agent technology, and the often mistaken perception that traditional software offers better returns on investment. This paper aims to redress this by developing a plan recognition framework for agent program learning, where behavior logs of legacy applications (or even manually executed processes) are mined to extract a 'draft' version of agent code that could eventually replace these applications …


Effect Of Rice Husk Ash On Workability And Strength Of Concrete, Avinash Babu Srinivasreddy, Timothy J. Mccarthy, Eric Lume Jan 2013

Effect Of Rice Husk Ash On Workability And Strength Of Concrete, Avinash Babu Srinivasreddy, Timothy J. Mccarthy, Eric Lume

Faculty of Engineering and Information Sciences - Papers: Part A

Rice husk ash (RHA) is an agricultural waste which is a pozzolanic material that can be blended with the cement for manufacturing concrete. Its use can reduce the environmental impact of the cement industry. The present study investigates the chemical and morphological nature of RHA and silica fume (SF). Both can be used to improve strength and durability properties of concrete. Particle size distribution, loss on ignition (LOI), X-ray diffraction analysis, scanning electron microscopic were conducted. The effect of replacement of cement 5%, 10% and 15% by weight with SF and RHA on compressive strength and workability has also been …


Effect Of Confining Pressure And Frequency On The Deformation Of Ballast, Pramod Kumar Thakur, Jayan Sylaja Vinod, Buddhima Indraratna Jan 2013

Effect Of Confining Pressure And Frequency On The Deformation Of Ballast, Pramod Kumar Thakur, Jayan Sylaja Vinod, Buddhima Indraratna

Faculty of Engineering and Information Sciences - Papers: Part A

Increasing the speed and frequency of trains with the same static axle weight imparts higher dynamic axle loads more frequently. When this occurs on existing track which has not been designed for such loading there can be increased rates of ballast degradation, characterised by unacceptable deformation and lateral spread, leading to more frequent requirements for track maintenance. Recent studies carried out at the University of Wollongong highlighted that confining pressure and frequency have a significant influence on the permanent deformation and degradation of ballast. However, confinement required to keep the deformation and degradation of the ballasted track to an acceptable …


Effect Of Cooling Rate On Oxidation Behaviour Of Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou Jan 2013

Effect Of Cooling Rate On Oxidation Behaviour Of Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

Oxidation characteristics of a microalloyed low carbon steel were investigated by a hot rolling mill combined with acceleration cooling system over the cooling rate range from 20 to 70°C/s. The effects of cooling rate after hot rolling on microstructure and phase composition of oxide scale were examined. The results showed that the increase of the cooling rate has a significant influence on the decrease of the grain size and surface roughness of oxide scale. A higher cooling rate promotes the formation of retain wustite and primary magnetite precipitation while suppression of eutectoid α-iron precipitates. This provides the possibility to enhance …


The Effect Of Slag Basicity On Spinal Inclusion Wettability, Hamed Abdeyazdan, Brian J. Monaghan, Neslihan Dogan, M Akbar Rhamdhani Jan 2013

The Effect Of Slag Basicity On Spinal Inclusion Wettability, Hamed Abdeyazdan, Brian J. Monaghan, Neslihan Dogan, M Akbar Rhamdhani

Faculty of Engineering and Information Sciences - Papers: Part A

Steel cleanness is an important and growing research area driven by the demands to produce high quality steel. Inclusion content in steel is an important criterion to assess clean steel. MgO.Ah03 spinel inclusions cause problems in steel processing and are generally deleterious to steel products due to their high melting point and high hardness. Jnclusions are generally r· moved by rea ting with slag. This is primarily achieved by optimizing lhe PI' 'ess omliLions to promote contact and reaction between the inclusion and S,l,lg '. or efticient rem val from the steel the inclusions must attach to and dissolve in …


Confinement Effect Of Frp And Transverse Steel On Retrofitting Square Concrete Columns, Le V. Doan, Xu Lei, Muhammad N. S Hadi, Thong M. Pham Jan 2013

Confinement Effect Of Frp And Transverse Steel On Retrofitting Square Concrete Columns, Le V. Doan, Xu Lei, Muhammad N. S Hadi, Thong M. Pham

Faculty of Engineering and Information Sciences - Papers: Part A

This study presents an experimental investigation into strain distribution of Fibre-Reinforced Polymer (FRP) in FRP-confined concrete columns with internal steel reinforcement under concentric and eccentric loading conditions. A total of nine reinforced concrete columns were cast and tested. Three of them were square in cross-section while the others were originally square but were shape-modified into circular columns with four pieces of segmental circular concrete covers and confined with three layers of CFRP. The nominal compressive strength of the segmental concrete covers was 40 MPa and 80 MPa. All columns were tested under concentric load, 25 mm or 50 mm eccentric …


Magnetism And The Magnetocaloric Effect In Prmn1. 6fe0. 4ge2, W D. Hutchison, Jianli Wang, S J. Campbell Jan 2013

Magnetism And The Magnetocaloric Effect In Prmn1. 6fe0. 4ge2, W D. Hutchison, Jianli Wang, S J. Campbell

Australian Institute for Innovative Materials - Papers

The magnetic and magnetocaloric properties of PrMn1.6Fe0.4Ge2around the ferromagnetic transitions T C inter ~ 230 K and T C Pr ~ 30 K have been investigated by magnetisation, 57Fe Mössbauer spectroscopy and electron paramagnetic resonance (EPR) measurements over the temperature range 5–300 K. The broad peaks in magnetic entropy around TC inter (intralayer antiferromagnetism of the Mn sublattice to canted ferromagnetism) and TC Pr (onset of ferromagnetic order of Pr sublattice in addition to ferromagnetically ordered Mn sublattice) are typical of second order transitions with maximum entropy values of -ΔS M ~ 2.0 J/kg K and -ΔS M ~ 2.2 …


Aging Effect Evolution During Ferroelectric-Ferroelectric Phase Transition: A Mechanism Study, Zuyong Feng, Zhenxiang Cheng, Dongqi Shi, S X. Dou Jan 2013

Aging Effect Evolution During Ferroelectric-Ferroelectric Phase Transition: A Mechanism Study, Zuyong Feng, Zhenxiang Cheng, Dongqi Shi, S X. Dou

Australian Institute for Innovative Materials - Papers

Aging can significantly modify the dielectric, piezoelectric, and ferroelectric performance of ferroelectrics. However, little attention has been paid to the aging effect during ferroelectric-ferroelectric phase transitions that is essentially correlated with real applications. In this letter, the authors report the aging effect evolution between two ferroelectric phases in an acceptor-doped piezoceramics. The results show that aging-induced double hysteresis loops were exhibited in different ferroelectric phases, but disappeared during ferroelectric-ferroelectric phase transitions, suggesting the mechanism that the intrinsic restoring force for the reversible switching of domains caused by the alignment of defect dipoles was weakened due to ferroelectric dipole reorientation.