bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface Modification-Based Fabrication of Double Surface Highly Reflective and Conductive Metallized Polymeric Films and Microstructural Tuning Nanocomposite Layers
Authors: Wu Zhan Peng , Wu De Zhen , Li Fang , Hong Feng Hong , Qi Sheng Li , Jin Ri Guang
Published: March 2009

Silvered polyimide films have been prepared by alkali hydroxylation of polyimide film
surface and incorporation of silver ions through subsequent ion exchange. Thermal curing had not
only re-cycloimidized the poly(amic acid) into polyimide, but also reduced silver ions into silver
atoms and near-atomic silver clusters, which diffused and aggregated to give reflective and
conductive surfaces without addition of reducing agents. By this method, silvered polyimide films can
be easily fabricated with double excellent reflective (reflectivity > 97%) and conductive surfaces
(surface resistance: 0.02 /sq), outstanding metal-polymer adhesion, high mechanical properties, and
controllable thickness of silver layers at modest cost. As the side-to-side near-surface microstructure
difference in the laboratory made samples and commercial PI films, the thickness of alkali induced
hydrolysis, loading of silver ions and forming of silver layers at the two sides of the polyimide films
were also discussed here. Films were characterized by transmission electron microscopy (TEM),
scanning electron microscopy (SEM) and tapping mode atomic force microscopy (AFM). Results
show that continuous silver layers were formed on the polyimide films.
Introduction of Li+ Ions into Anodic Film by Hydrotalcite Precursor and Electrochemical Behavior
Authors: Ye Hao , Zuo Yu , Xiong Jin Ping , Zhao Jing Mao
Published: March 2009

Lithium ion was introduced into high purity aluminum (99.999%) by hydrotalcite
precursor method, and Li/Al composite anodic film was obtained by anodizing. The methods of
X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron
microscopy (SEM) were used to investigate the properties of the anodic film. The electrochemistry
behaviors of composite anodic film were studied by means of potentiodynamic method and
electrochemical impedance spectroscopy (EIS). The results showed that the composite anodic film
was produced by hydrotalcite precursor method and which is amorphous to X-ray diffraction. The
passivation current density of the anodic film in NaCl solution (1mol/L, pH=3, 7, 11) decreased
obviously, while impedance value increased sharply. Corrosion resistance of the composite anodic
film in NaCl solution was improved by the introduction of Li+ ion.
Discussion on the Process and Performance Research of Hemp Viscose Fiber
Authors: Zhou Yong Kai , Cao Ling , Zhang Jian Chun
Published: March 2009

this paper mainly studies the craft on how to produce viscose by using hemp fiber and
affection of the process on the original property of the hemp. Meantime, the authors test and
analyze the property of viscose fiber after the spinning process. The result shows that the
crystallinity, and orientation degree of the culm of hemp are low. And the physical performance of
hemp viscose is better than that of ordinary cotton viscose.
Hydrothermal Synthesis and Characterization of Vanadium Oxide Nanotubes
Authors: Wei Jia , Zhang Jing Chang
Published: March 2009

Vanadium oxide nanotubes (VOX-NT) have been synthesized by using amine as structure-directing template and V2O5 as precursor under hydrothermal conditions (160°C, 7 days). The XRD, FTIR and TEM have been performed to optimize the synthesis conditions such as the amine species and the molar ratio between V2O5 and amine. The results of TEM show that the same molar ratio of V2O5 and butylamine (1.0:1.0) produce a mass of nanotubes which have intact figuration. The diameters are about 80nm for most of the nanotubes prepared by V2O5 and octadecylamine. While the obtained VOX-NT prepared by V2O5 and n-butylamine were found having diameters from 28.51nm to 97.80nm and the distance between the vanadium oxide layers is 1.84 nm comfirmed by XRD. FTIR also display that some changes of the structure have been occurred during the formation of the nanotubes compared with the staring materials.
Titania Nanotubes Prepared by Templating Needle-Like Calcium Carbonate
Authors: Gao Li Dong , Chen Jian Feng
Published: March 2009

Titania nanotubes were successfully synthesized by a simple procedure with needle-like CaCO3 as inorganic templates at a room temperature in nonaqueous system. Through the hydrolysis of tetrabutoxytitanium (TBOT), titania crystal nucleus were deposited on the CaCO3 nanoparticles due to heterogeneous nucleation, followed by aggregation condensation on the surface of needle-like CaCO3 cores and removal of CaCO3 to produce hollow titania nanotubes. Its morphological and structural properties were characterized by TEM, SEM, and XRD, respectively. The nanotubes have a uniform tubular hollow structure with one or two big openings ends, the length of about 2.0 μm, the average inner diameters of 100-200 nm, respectively, and a wall thickness of approximately 40 nm. The phase formed was anatase after calcinations at 723 K for 2 h and nanotubes with hollow structure remained their original shapes, and the BET surface area of as-synthesized titania nanotubes was 243.45 m2/g, and decreased to 144.76 m2/g after calcinations
Research on the Advanced Glasses and Glass-Ceramic Materials in Central South University
Authors: Lu An Xian , Liu S.J. , Ke Z.B.
Published: March 2009

Based on the results in glass scientific research fields such as the National Natural
Science Foundation project—forming and structure of heavy metal oxide glass, national defense
new material projects and various other research projects, the new achievement and the present
progress on the investigation in non-crystalline science exploration and the development for new
kinds of glass materials in the school of Materials Science and Engineering of Central South
University are briefly introduced in this paper.
Preparation of Magnetically Soft, Highly-Densified Fe Cluster-Assembled Films by Impact Cluster Deposition
Authors: Peng Dong Liang , Sumiyama K. , Yamada H. , Hihara Takehiko , Uchida T.
Published: March 2009

Highly-densified Fe cluster-assembled films were obtained at room temperature by an
energetic cluster deposition. Fe clusters were produced using a plasma-gas-condensation (PGC)-type
cluster deposition apparatus with a high cluster productivity. Ionized clusters in a cluster beam were
electrically accelerated and directly deposited onto a substrate together with neutral clusters from the
same cluster source. By increasing the impact energy of the ionized clusters up to about 1 eV/atom,
the obtained cluster-assemblies have packing fractions higher than 0.8 without any serious size
change, and result in a soft magnetic behavior up to a frequency range of few hundred MHz.
Organization of Photosynthetic Antenna Complex in Lipid Bilayers
Authors: Dewa Takehisa , Yoshida K. , Sugimoto M. , Sugiura R. , Nango M.
Published: March 2009

Bacterial photosynthetic antenna complexes are composed of α-helical hydrophobic polypeptides and pigments (e.g., bacteriochlorophyll a). We report here self-assembling properties of an engineered hydrophobic polypeptide with zinc-substituted bacteriochlorophyll a ([Zn]-BChl a) in various lipid bilayer to investigate the effect of lipid species on the self-assembling properties. When the polypeptide and [Zn]-BChl a were mixed in surfactant solution (n-octyl β-D-glucopyranoside: OG) at 25°C, the absorption band [Zn]-BChl a was red-shifted from 770 to 812 nm, that is assignable to quasi-dimeric “subunit-type” complex. By subsequent dilution and cooling of the solution, the absorption band further red-shifted to 836 nm indicative for progressed assembly, ‘LH1-type’ complex. When the subunit-type complex was assembled in lipid bilayer, e.g., phosphatidylcholines (PC’s) and phosphatidylglycerol (PG’s), the assembling property to form LH1-type complex prominently depended on the character of their fatty acid chains in the phospholipids. The subunit complex remained in the fluidic bilayers, but further assembled to form LH1-type complex in solid-like phospholipid bilayers, suggesting that intermolecular force of phospholipid governs the assembling of the polypeptide/[Zn]-BChl a complex.
Influence of Anodizing Process on Cohesive Property of Anodic Films on Aluminum Alloy with Rubber
Authors: Zhang Xiao Feng , Zhang Jing Sheng , Lu Yong Lai , Liu Yan Dong , Liu Li , Zuo Yu , Li Wen Gang
Published: March 2009

The bonding properties between the solution polymerized styrene-butadiene rubber
(SSBR) and 2A70 aluminum alloy with treatment of anodic oxidation by sulfuric acid or ethane
acid were investigated. The influences of three treating methods were also studied. Two drying
methods, which are vacuum method and normal pressure method affected on the properties of
adhesive molecular immerging into the hole dispersing on the surface of aluminum alloy, were
discussed. The results revealed that prolonging the time for anodic oxidation by both sulfuric acid
and ethane acid can increase the thickness of the aluminum oxide layer.
Anodic Oxidation Parameters on Al-Cu Alloy Anodizing Film's Electrochemical Ability by EIS
Authors: Guo Chao , Zuo Yu , Zhao Jing Mao , Zhao Xu Hui , Xiong Jin Ping
Published: March 2009

EIS is used in this paper to study the effects of anodic oxidation parameters on the film’s ability, and multi-layer equivalent circuits are proposed. The oxidation time has great effect on porous layer, the porous layer’s impedance increases as the anodic oxidation time prolong; anodic current density has effect on both barrier layer and porous layer, higher current density gets higher impedance values in both barrier layer and porous layer; anodic oxidation temperature has great effect on barrier layer, when the temperature decreases, the barrier layer’s impedance increases.
Simulation of Static Test of Air-Spring
Authors: Li Feng Xiang , Yang Wei Min , Ding Yu Mei
Published: March 2009

A method for testing an air-spring was advanced in the beginning. Then ANSYS was
utilized to simulate the static test. In the simulation, multiple load steps solution was carried out
through APDL *DO-LOOP and array parameter method. Scalar parameter PRESSURE was
established as inner pressure tracking parameter to update inner pressure. Table parameter
PRESSURES was established as inner pressure output parameter to export inner pressure of each
load step. Comparison was done between simulation result and test data to prove the feasibility of
simulation. Finally, some major parameters such as cord angle and initial inner pressure were taken
into account, which had remarkable effect on the air-spring’s performance.
Research of Equipment Applied for Distillation of Viscous and Self-Polymerized Materials
Authors: Pi Yao , Li Qun Sheng , Liang Zuo Dong , Liu Hui Ying
Published: March 2009

Distillation column of special materials having high viscosity or containing solid
particles, etc in chemical and petrochemical process is studied in this paper. Packed-column does
not fit into this situation and even in a plate column, because of high flow resistance on the plate; it
will cause some problems, such as blocking, flooding and shutting down. Here the hydrodynamic
performance of flow-guided fixed valve trays (FFVT) is introduced and its hydrodynamic
performance has been experimentally studied. With flow-guided holes and trapezoid fixed valves to
transfer momentum of the gas bursting forth in a horizontal way to the liquid, the flow on the FFVT
is well-proportioned and stable. The hydrodynamic data have been correlated and equations have
been obtained for the pressure drop, the entrainment and the gas velocity at weeping point, which
can be used for the design of FFVT.
Development of High-Temperature Acoustic Emission Sensor Using Aluminium Nitrade Thin Film
Authors: Noma Hiroaki , Ushijima E. , Ooishi Y. , Akiyama Morito , Miyoshi N. , Kishi K. , Tabaru Tatsuo , Ohshima I. , Kakami A. , Kamohara T.
Published: March 2009

Aluminum nitride (AlN) is a promising Acoustic Emission (AE) sensor element for
high-temperature environments such as gas turbines and other plants because AlN maintains its
piezoelectricity up to 1200°C. Highly c-axis-oriented AlN thin-film sensor elements were prepared
on silicon single crystals by rf magnetron sputtering. Both ordinary-temperature AE sensors and
high-temperature AE sensors have been developed using these elements. In this paper, to study effects
of d33 and thickness of AlN elements on sensor sensitivity, AlN elements with d33 from 2 to 7 pm/V
and thickness from 3 to 9 /m were prepared. It is confirmed that the AE sensor sensitivity increased
with d33 and thickness of AlN elements. The sensitivity of the high-temperature AE sensor was also
improved by a design of the sensor structure. The sensor characteristics were evaluated at elevated
temperatures from 200 to 600°C. It was confirmed that the AE sensor works well at 600°C and does
not deteriorate.
Investigation of Fatigue Crack Growth on Material for Reactor Pressure Vessel by Acoustic Emission
Authors: Svoboda Václav , Žemlička F. , Brumovský M.
Published: March 2009

Contribution contains an application of acoustic emission method during instability and
growth of fatigue crack in reactor pressure vessel specimen loaded by means of bending.
Material of specimen was typical material of pressure water reactor vessel covered by austenitic
cladding as a protection layer against corrosion. Specimen had shape of prism with defect in the
middle where fatigue crack was created very close to austenitic cladding.
Loading of specimen was done in special loading machine with defined speed of loading resp.
increased force.
Investigation of instability and propagation of inertial crack was observed by acoustic emission
technique, potential drop method, by using of straingauges and by high-speed camera.
Acoustic emission sensors were located from both sides of specimen.
By this experimental technique was possible to observe "pop-in" of crack during loading.
Different types of specimen with different mode of aging were investigated.
Results of acoustic emission activity are described graphical curves in relation to individual
stages of loading.
Electromagnetic and Acoustic Emission Fine Spectra
Authors: Sikula Josef , Majzner J. , Sedlak P. , Mori Yasuhiko
Published: March 2009

A new measuring method for the detection of fine spectra of electromagnetic and acoustic
emission (EME and AE) signals from small cracks is described. It requires wide band ultra-low
noise amplifiers, analogue filters, the optimization of signal to noise ratio of sensors and the
application of noise elimination methods. Analyses of noise sources in sensors and preamplifiers are
given. They are thermal noise, polarization noise and low frequency 1/f noise. Measuring set-up
background noise suppression involving also the electromagnetic shielding allows us to detect
signals in the range of 1 to 100 nV. This measuring set-up was used to observe crack initiation in
granite samples. AE and EME signals show different behaviour in the first interval of about 20 μs
just after crack initiation. For the first stage of crack initiation the frequency spectrum of EME
signal is given by the eigen vibrations of crack walls, by the internal friction and the sample
electrical conductivity. We observed that the crack opening and crack wall vibration create the high
frequency signal in the frequency band up to 10 MHz. These signals were observed in the first time
interval of about 20 μs. After that the frequency spectrum is given by the sample eigen vibration or
the sample boundary conditions, and we have observed the spectra in the frequency range 100 kHz
to 2 MHz.
Dynamic Behavior of Two Types of Martensitic Transformations in Cu-Al-Ni Shape Memory Alloy Single Crystal by Acoustic Emission Method
Authors: Yoshida Kenichi , Yasuda T. , Tani D. , Nishino H.
Published: March 2009

Dynamic behavior of two types of martensitic transformations during tensile deformation
of Cu-Al-Ni shape memory alloy single crystal has been investigated using an acoustic emission
waveform analysis. Two kinds of martensitic transformations consist of β1 ⇔ β1′ (structural change
of DO3 to 18R) and β1 ⇒ γ1′ (structural change of DO3 to 2H), each of which is called super-elastic
and thermo-elastic martensitic transformations, respectively. These two types of martensitic
transformations could be obtained during tensile deformation because of different heat treatment.
The rise time at the source (the source rise time) in finite elastic solid by the modified Takashima’s
method was analyzed using the acoustic emission waveform detected during the martensitic
transformation. The mean source rise time to the γ1′ phase was smaller than that to the β1′ phase
before yielding and became the same after yielding. The former result means that the nucleation of
the γ1′ phase is faster than that of the β1′ phase because of different crystallographic structure. The
latter result is that the growth rate of the γ1′ phase is the same as that of the β1′ phase.
Damage Mechanisms in Loaded Aramid Composites by Means of Embedded PVDF Acoustic Emission Sensors
Authors: Caneva Claudio , De Rosa I.M. , Sarasini F.
Published: March 2009

Cost-effective and reliable damage detection is critical for the utilization of composite
materials due to the relatively localised nature of damage formation and the resultant reduction in
structural integrity. Of the methods available, Acoustic Emission (AE) is considered as one
potential technology for on-line and in situ monitoring of structural degradation of composite
materials.
Purpose of this work was to study the interaction between embedded PVDF (polyvinylidene
fluoride) transducers and composite samples as well as detect and characterize the failure
mechanisms in aramid/epoxy flexural test specimens using acoustic emission data obtained by
embedded PVDF film sensors. Furthermore, it has been realized a comparison with surface
mounted PVDF data. Results of our previous works (Caneva et al., 2005) dealing with monitoring
tensile and flexural behaviour of glass/epoxy composites enabled to extend this methodology to
aramid/epoxy composites.
The use of Acoustic Emission and Scanning Electron Microscopy (SEM) observations enabled
to identify and understand the failure mechanisms of the composites tested. Furthermore,
satisfactory results of this work highlighted that the application of PVDF shows promise as a
suitable acoustic emission transducer for fibrous composite materials.
AE-Testing in Potentially Explosive Atmospheres - From the Requirements to an Intrinsically Safe System-Certified Realization
Authors: Vallen Hartmut , Vallen J. , Forker J.
Published: March 2009

Measurement apparatus intended for use in potentially explosive atmospheres in Europe,
must comply with the EC Directive 94/9/EC, also known as “ATEX directive”. The conformity
must be verified by a so called ATEX Certificate.
In the frame of the EC-funded research project „Corrosion testing of tank ships“, AE-field tests
on board large tank ships were executed. Intrinsically safe certified AE sensors were temporarily
immersed through a potentially explosive atmosphere from the tank top through manholes into the
liquid contents.
Ship owners and involved classification societies insisted on the availability of a system
certificate confirming intrinsic safety for the used sensors and isolation barriers and also for the
whole installation for protection from the risk of a lightning strike into a signal cable running over
deck. For this certification process, all details of installation, such as cabling, earthing, over voltage
protection, etc., have been decided, explained and examined.
This paper presents some basics of explosion protection with its terminology and the new
“Product Family ISAFE“.
Continuous AE Monitoring of Structures – Can it Be Both Easy to Use and Effective?
Authors: Holroyd Trevor J.
Published: March 2009

The use of AE for testing the integrity of structures has a long history but its use for
continuous monitoring of structures is not so well established. In a world of ageing infrastructure
the need for methods of continuous monitoring is increasing so that the operation, maintenance and
repair of structures can be more effectively managed. The extent to which AE will play a role in
this obviously depends upon how effective it is in providing the wanted information in a timely
manner to those who need it. However, other crucial aspects in its adoption will be the ease with
which it can be used (e.g. specified, installed, interpreted) as well as its reliability and lifetime
costs. With these considerations in mind, a multi-channel monitoring system has been developed
called SIMPALTM. Throughout its development, field trials have been conducted with the aim of
exploring the practical usefulness of a simpler kind of AE system. This paper provides an overview
of the approach taken in developing the system and presents data gathered during proving trials and
from its practical application to structures such as bridges.
Acoustic Emission Waveform Changes for Varying Seeded Defect Sizes
Authors: Al-Dossary S. , Raja Hamzah R.I. , Mba D.
Published: March 2009

The investigation reported in this paper was centered on the application of the Acoustic
Emissions (AE) technology for characterising the defect sizes on a radially loaded bearing. The aim
of this investigation was to ascertain the relationship between the duration of AE transient bursts
associated with seeded defects to the actual geometric size of the defect. It is concluded that the
geometric defect size can be determined from the AE waveform.
Use of AE Based Instrumentation to Monitor Machinery Condition in the Industrial Environment
Authors: Holroyd Trevor J.
Published: March 2009

The use of AE by maintenance personnel for monitoring the condition of rotating
machinery on the industrial shop floor is now well established and provides both a quick and
effective assessment. Despite early resistance, especially by those accustomed to vibration based
monitoring, it now enjoys a widespread acceptance. The development of signal processing routines
and instrumentation specifically for the condition monitoring role has been a major factor in this
achievement. Experience has shown that as a portable instrument AE can be very quickly applied
and give instant indications of machine condition with high sensitivity to fault conditions.
Appropriately pre-processed AE signals are particularly useful for on-line monitoring since the fault
indications are in general less affected by changes in operating conditions than vibration based
techniques as well as being far simpler to interpret. This is especially important where many
machines are being simultaneously monitored. This paper discusses the accompanying
developments and presents illustrative application examples.
Progress Towards a Forward Model of the Complete Acoustic Emission Process
Authors: Wilcox Paul D. , Lee C.K. , Scholey Jonathan J. , Friswell Michael I. , Wisnom M.R. , Drinkwater B.W.
Published: March 2009

Acoustic emission (AE) techniques have obvious attractions for structural health
monitoring (SHM) due to their extreme sensitivity and low sensor density requirement. A factor
preventing the adoption of AE monitoring techniques in certain industrial sectors is the lack of a
quantitative deterministic model of the AE process.
In this paper, the development of a modular AE model is described that can be used to predict
the received time-domain waveform at a sensor as a result of an AE event elsewhere in the
structure. The model is based around guided waves since this is how AE signals propagate in many
structures of interest. Separate modules within the model describe (a) the radiation pattern of guided
wave modes at the source, (b) the propagation and attenuation of guided waves through the
structure, (c) the interaction of guided waves with structural features and (d) the detection of guided
waves with a transducer of finite spatial aperture and frequency response. The model is
implemented in the frequency domain with each element formulated as a transfer function. Analytic
solutions are used where possible; however, by virtue of its modular architecture it is
straightforward to include numerical data obtained either experimentally or through finite element
analysis (FEA) at any stage in the model. The paper will also show how the model can used, for
example, to produce probability of detection (POD) data for an AE testing configuration.
AE Sensor Calibration for Out-of-Plane and In-Plane Displacement Sensitivity
Authors: Theobald Pete T. , Dar F.
Published: March 2009

This paper proposes a method for both the out-of-plane and in-plane displacement
sensitivity calibration of an acoustic emission (AE) sensor. In the method, a laser homodyne
interferometer is used to measure the out-of-plane and in-plane displacement of the surface of a
large test block excited by a repeatable source transducer. The out-of-plane displacement is
measured by aligning the laser beam perpendicular to the surface with time gating of the receive
waveform used to isolate only the direct arrival of the longitudinal wave produced by the piston
source transducer. For the in-plane displacement measurement, the laser beam is aligned parallel to
the surface to intersect a small optically reflective step with the time waveform being gated to
measure only the direct shear arrival produced using a normal incidence shear wave source
transducer. In each case, the interferometer measurement is followed by coupling the sensor under
test to the measurement surface, which is then exposed to the same acoustic field and the sensor
output signal measured. This substitution method allows the sensor sensitivity to be obtained in
terms of volts per unit displacement for both the out-of-plane and in-plane surface displacement.
The method allows a comprehensive description of an AE sensor response to different planes of
displacement and offers the potential for a traceable sensor calibration to units of length.
Fold Defects in Aluminum Alloy A356 Lost Foam Casting
Authors: Jagoo S. , Ravindran Comondore , Nolan Dennis
Published: March 2009

In the lost foam casting (LFC) of aluminum alloys, the expandable polystyrene (EPS)
foam characteristics (foam composition, polymer processing and bead fusion) influence the
formation of deleterious fold defects in the final casting. In this research, four types of EPS beads
were investigated: (1) the regular EPS beads, (2) 2wt% hexabromocyclododecane and 2wt%
dicumyl peroxide added to the EPS beads during the polymerization process, (3) 2wt% silicaalumina
blended to EPS beads after the pre-expansion process of the beads and (4) 2wt%
hexabromocyclododecane blended to EPS beads after the pre-expansion process of the beads. The
density of the regular and modified EPS beads was kept constant at 25.63 kg/m3. Aluminum alloy
A356 was poured at 1023 K into the window pattern. The window patterns with regular EPS beads
did not fill completely and had identifiable carbon/oxide defects on the surface. The window
patterns with the additives were completely filled with a few surface defects. From
thermogravimetric analysis (TGA), it was found that the EPS beads with silica-alumina had a
reduced onset temperature of degradation of EPS (from 634 K to 618 K) and a reduced activation
energy (from 188 kJ/mol to 147 kJ/mol) relative to the regular beads. In the organic brominatedmodified
EPS (both through blending and polymerization), it was found that the value of the
preexponential (rate equation) was significantly increased. Through light optical microscopy
(LOM) and scanning electron microscopy (SEM), it was found that the polymerization process
additives increased the degree of bead fusion whereas the post pre-expansion additives decreased
the degree of bead fusion. Finally, the EPS beads treated during the polymerization process
produced castings with the least overall surface, subsurface and internal defects.
The Influence of Chemical Alloying on the High Temperature Wear Resistance of H-Free DLC Coatings
Authors: Galvan Damiano , Pei Yu Tao , de Hosson Jeff T.M. , Cavaleiro Albano
Published: March 2009

A commercial RF-sputtering deposition rig was employed to deposit H-free diamond-like
carbon (DLC) coatings. The influence of alloying elements such as Ti and Si on the structure,
mechanical and tribological properties of the coatings was investigated. The coating was observed in
cross section and in plan view with SEM, TEM and AFM. Because of the highly-ionized plasma
generated by the RF-powered glow discharge, ion bombardment suppresses the formation of a
columnar structure regardless of the composition of the coatings. The method produces featureless
microstructures and smooth surfaces. TEM investigations confirm that no crystalline phases form in
the coatings regardless of the presence of considerable concentrations of Ti and Si. Tribological tests
were performed with a high-temperature tribometer in a ball-on-disk configuration, using coated
disks and different materials for the ball countepart. At ambient T the sliding friction coefficient
decreases as the concentration of alloying elements increases. Nevertheless, high-T tribotests with a
constant thermal load showed that the presence of alloying elements decreases the thermal stability of
the coatings. For each coating a temperature exists above which a sudden increase of friction
coefficient is observed, with subsequent detachment and failure of the coatings. The mechanism of
disruption of the self-lubrication effects is identified and the influence of the alloying elements on the
thermal degradation of tribological performance of the coatings is discussed.
Synthesis of Intermetallics Based on the Fe-Al-Si-Zn Alloy System by Magneto-Mechanical Milling of Ductile Elemental Powders
Authors: Carpenter Kristin R. , Dippenaar Rian , Phelan Dominic , Wexler David
Published: March 2009

The Zincalume hot-dip coating process is a well-established technique for excellent corrosion
protection of steel products. This paper describes the study of two intermetallics based on the Fe-
Al-Si-Zn alloy system, α-AlFeSi and α-AlFeSi(+Zn), pertinent to the Zincalume process. These
intermetallics are difficult to characterize in-situ due to their formation at high temperature and
because they form as very thin intermetallic layers on a steel substrate, which inhibits accurate
quantitative analysis. Controlled magneto-ball milling and hot-pressing have been employed in an
attempt to synthesise these intermetallic compounds.
Magneto-ball milling, under a He atmosphere, was conducted in shearing mode to enable controlled
milling of elemental powders, namely Zn and Al, without the excessive cold-welding often
associated with milling of ductile powders with high coefficients of surface friction. XRD analysis
indicated that uniform mixtures of highly reactive fine-structured powders were produced, as
indicated by diffuse elemental peaks of low intensity. Hot-pressing was utilized to sinter the
powders into compact intermetallic compounds without sintering aids. The intermetallics were
characterized by DTA, XRD and elemental contrast mapping performed on an SEM with EDS.
Evaluation of the Adhesion of Ultra-Thin Teflon-Like Films Deposited by Plasma on 316L Stainless Steel for Long-Term Stable Drug-Eluting Stents
Authors: Lewis François , Maheux-Lacroix Benoit , Turgeon Stephane , Mantovani Diego
Published: March 2009

Metallic intravascular stents are medical devices commonly made of 316L stainless steel or
nitinol used to scaffold a biological lumen, most often diseased arteries, after balloon angioplasty.
Stenting procedures reduce the risk of restenosis, but do not eliminate it completely. Indeed,
restenosis remains the principal cause of clinical complications, leading to up to 30 % of failure after
3 months of implantation. During the last few years, several works have been focused on the
development of an appropriate coating able to act as a carrier for specific anti-restenosis drugs.
Moreover, this coating would act as an anti-corrosive barrier, thus inhibiting the release of potentially
toxic ions. Actually, the main challenges in stent coatings are to synthesize a biocompatible polymer
coating resistant to blood flow, wall shear stress and tensile force after the stent deployment which
results in a permanent strain of up to 25%. The adhesion and chemical resistance after deployment are
critical properties to investigate for the improvement of the long-term reliability of polymer coated
stent. The aim of this study was to evaluate the effect of a 25% equivalent plastic deformation on
chemical, mechanical and adhesion properties of Teflon-like films deposited on 316L stainless steel.
These properties were studied by chemical spectroscopy and atomic force microscopy. Teflon-like
films were deposited by pulsed plasma glow discharges on flat electropolished 316L stainless steel.
An original method has been developed to induce the deformation, and preliminary results have
showed that the 12 nm thick Teflon-like films successfully resist to deformations of up to 25%.
Microstructure and Properties of Laser Fused Nickel Based Self Fluxing Alloy Coating
Authors: Li Yu , Nishio Kazumasa , Katoh Mitsuaki , Yamaguchi Tomiko
Published: March 2009

The thermal sprayed coatings are widely used in waste incineration boilers and fossil fuel-fired
boilers. However, the defects, such as porosity, cracks and unmelted particles, in these coatings are
detrimental to corrosion performance. In this study, the nickel based self fluxing alloy coating was fused
by YAG laser to improve performance of the coating. Under appropriate laser parameters, the nonporous,
crack-free coating was produced. The rubber wheel type abrasion wear test and hot corrosion test conducted
in the presence of a mixed salt of Na2SO4/NaCl/KCl at 650°C showed that the modified coating exhibited
excellent wear and corrosion resistances compared with the as sprayed and gas fused coatings.
Low Temperature Crystallization and Structural Modification of Plasma-Sprayed Hydroxyapatite Coating with Hydrothermal Treatment
Authors: Yang Chung Wei , Lui Truan Sheng , Chang Edward
Published: March 2009

The effect of autoclaving hydrothermal treatment on the characteristics of
plasma-sprayed hydroxyapatite (HA) coatings on the Ti-6Al-4V substrate was investigated. The
heating temperatures were 100°C, 150°C and 200°C with ambient saturated steam pressure in an
autoclave. On the basis of quantitative analysis of crystallinity using x-ray diffraction (XRD),
hydrothermal treatment was found to be effective for increasing the crystallinity and phase purity of
the HA coatings. The prominent and sharp OH− and PO4
3− peaks detected from x-ray photoelectron
spectroscopy (XPS) and Fourier transform infrared (FT-IR) spectra demonstrate a superior
crystallized integrity of hydrothermal-treated HA coatings through the incorporation of water vapor.
Moreover, the significant presence of OH− peak in XPS spectra represents a replenishment of water
molecules which tends to reduce the dehydroxylation state of as-sprayed HA coatings. From the
observation of microstructures, crystallized HA was found to diminish the spraying defects of
hydrothermal HA coating layers, and finely-crystallized HA crystals, with a Ca/P atomic ratio of
1.67, were observed through transmission electron microscopy (TEM). Hydrothermal treatment
could induce a low-temperature crystallization process, and the saturated steam pressure is thought
to be a factor which reduces the activation energy and accelerates the HA crystallization.
Experimental evidence confirmed that the ambient saturated steam pressure plays an important role
in lowering heating temperatures and promoting HA crystallization.
Solid Free-Form Fabrication of Metallic Components
Authors: Kagawa Akio , Mizumoto Masayuki , Ohgai Takeshi
Published: March 2009

The influence of process parameters on shape stability and surface smoothness of
cylindrical and rectangular castings produced by fused spinning deposition (FSD) method was
investigated. The optimum conditions to control the shape and smoothness of side surface of the
castings produced by the FSD method without water-cooling were limited to a narrow range of
process parameters. The casting with a stable shape and a smooth side surface was obtained with the
aid of water-cooling. The tensile strength of the castings produced by the FSD method was 1.4 times
higher than those of the specimens cast into metal-mold and sand-mold, due to a finer equiaxed grain
structure of the FSD castings. Employing the combination of the deposition patterns for tube and solid
castings, some practical metallic components were fabricated by the FSD method.
Coupled Modeling of Electromagnetic Field, Fluid Flow, Heat Transfer and Solidification during Conventional DC Casting and Low Frequency Electromagnetic Casting of 7XXX Aluminum Alloys
Authors: Zhang Hai Tao , Nagaum Hiromi , Zuo Yu Bo , Cui Jian Zhong
Published: March 2009

A comprehensive mathematical model has been developed to describe the interaction of
the multiple physics fields during the conventional DC casting and LFEC (low frequency
electromagnetic casting) process. The model is based on a combination of the commercial finite
element package ANSYS and the commercial finite volume package FLUENT, with the former for
the calculation of the electromagnetic field and the latter for the calculation of the magnetic driven
fluid flow, heat transfer and solidification. Moreover, the model has been verified against the
temperature measurements obtained from two 7XXX aluminum alloy billets of 200mm diameter,
cast during the conventional DC casting and the LFEC casting processes. In addition, a
measurement of the sump shape of the billets were carried out by using addition melting metal of
Al-30%Cu alloy into the billets during casting process. There was a good agreement between the
calculated results and the measured results. Further, comparison of the calculated results during the
LFEC process with that during the conventional DC casting process indicated that velocity patterns,
temperature profiles and the sump depth are strongly modified by the application of a low
frequency electromagnetic field during the DC casting.
Laser Alloying with WC Ceramic Powder in Hot Work Tool Steel Using a High Power Diode Laser (HPDL)
Authors: Piec Marek , Dobrzański Leszek Adam , Labisz Krzysztof , Jonda Ewa , Klimpel Andrzej
Published: March 2009

Investigations include alloying the X38CrMoV5-3 hot-work tool steel surface layer with
the tungsten carbide, using the high power diode laser (HPDL). The tungsten carbide ceramic
particles of the medium grain size according to FSSS = 50 /m were introduced using the rotor
conveyer to improve the properties of the surface layer. The powder feed rate was set at the steady
level of 8.64g/min. Remelting and alloying were carried out several times in the laser power range
of 1.2 – 2.3 kW in the remelting/alloying, alloying/remelting sequences. The structural mechanism
was determined of gradient layer development, effect was studied of alloying parameters, gas
protection method, and powder feed rate on its mechanical properties, and especially on its
hardness, abrasive wear resistance, and roughness. Structure changes were revealed consisting, in
particular, in its refining, and also hardness and microhardness changes in comparizon to the nonremelted
steel. Examination results obtained with the EDX microanalysis, surface and linear
analysis of the chemical composition, as well as the X-ray qualitative phase analysis are presented.
Immobilization of Poly(Ethylene Glycol) Terminated with Amine to Titanium Surface by Electrodeposition
Authors: Tanaka Yuta , Doi Hisashi , Iwasaki Yasuhiko , Yoneyama T. , Hanawa Takao
Published: March 2009

In many applications such as catheters, artificial blood vessels and diagnostic sensors,
blood compatibility or prevention of adhesion of platelet is required. The preferred way to control
these purposes is to eliminate or drastically reduce the adsorption of proteins. Surface modification
with Poly(ethylene glycol), PEG has long been known to reduce undesirable protein adsorption. No
technique for the immobilization of PEG to base metal has been developed. In this study, PEG
terminated at both terminals or one terminal with amine bases was immobilized onto titanium
surface by immersion or electrodeposition. The bonding manners of PEG onto titanium, which
involve directionality of terminated amines and chemical bonding states of interface between the
deposited PEG layer and TiO2, were characterized using X-ray photoelectron spectroscopy, XPS.
As a result, terminated amines locate inside of the PEG layer and combine mainly with TiO2 as
stable NHO by electrodeposition, while amines randomly exist and show mainly unstable bonding
with TiO2 by immersion. Moreover, the difference of amine termination leads to different bonding
manners, U-shape in PEG terminated both terminals and brush in PEG terminated one terminal.
This immobilization process is one-stage convenient technique and useful for all electroconductive
and morphological materials.
Fabrication Process of Carbonaceous Fiber Reinforced Al and/or Mg Alloy(s) Composites by Squeeze Casting
Authors: Uozumi H. , Kobayashi K. , Masuda Chitoshi , Yoshida M.
Published: March 2009

Carbonaceous fiber has high strength, high modulus and high thermal conductivity.
Preforms were fabricated by suction filtration method. Regardless of fiber type, the buckling
strength and elastic modulus of preforms increased with quantity of aluminum borate (AlBO)
whisker addition. The carbon nano tube (CNT) preforms were not buckled but only elastically
compressed. Carbonaceous fiber reinforced Al, Mg composites were fabricated by squeeze casting.
CF+AlBO hybrid reinforced composites were fabricated with 5% or less deformation. On the other
hand, 60% deformation was found in CNT+50AlBO hybrid reinforced composites.
Study of Waste Plastics as Composites Material in Cement Concrete Construction
Authors: Parasivamurthy Prakash
Published: March 2009

The rapid Urbanization and Industrialization all over the world has resulted in large
deposition of Plastic waste. This waste can be utilized under proper condition to reduce the
Cement content in Concrete.M20 concrete is used for most of the constructional works, since it
gives maximum strength. The strength of this concrete was compared with concrete obtained
of shredded Plastic waste varying from 2-8%. Experimental investigations comprised of testing
physical requirements of coarse aggregates, fine aggregates, cement and the modifier. M20
concrete was prepared as per IS SP: 23-1982. The said percentage of modifier was blended
with the cement concrete mix and the optimum modifier content was found. Cubes were cast
and tested for 1, 3, 7, 14 and 28 day strength. These tests revealed that by adding modifier, the
strength of concrete increased. At 5% optimum modifier content, the strength of the modified
concrete was found to be 1.2 times greater than the plain cement concrete. By using Plastic
waste as modifier, we can reduce the quantity of cement and sand by their weight, hence
decreasing the overall cost of construction .The Modified cement concrete can be used in the
construction of small drainage works and rigid pavement. Which leads to decrease in the overall
thickness of the pavement.
Nanostructured TiC1-X - TiB2 Composites Obtained by Metastability Processing
Authors: Atías Adrián Isabel C. , Vallauri Dario , Zhang Z. , Chrysanthou A. , DeBenedetti Bruno , Amato Ignazio
Published: March 2009

Non-oxide ceramic nanostructured powders are synthesized through metastable transformation
processing based on the Self-propagating High-temperature Synthesis (SHS) process followed by
quenching. Binary systems like the investigated TiC–TiB2, when quenched from the liquid state
give rise to metastable structures capable of being converted into a stable, fine-grained
(nanocomposite) microstructure upon recrystallization by medium temperature treatments. A
necessary condition is that the combustion temperature of the SHS reaction is higher than the
eutectic temperature.
A previous optimisation of the reaction stoichiometry was carried out to obtain SHS products
with composition approximately equal to the eutectic (i.e. 67%mol TiC0,7 – 33%mol TiB2),
according to the reaction: 6Ti + B4C + 1.8C → 4TiC0.7 + 2TiB2.
In this work, different amounts of sodium borate (borax) were used in order to determine the
optimum amount of additive to produce nanostructured TiC0.7–TiB2 composites. The morphological
evolution of the powders after thermal treatment yielding re–crystallized structures demonstrates
the metastability of the SHS–quench products. Therefore, the metastability process based on SHS–
quench represents an extremely attractive route suitable for the achievement of nanocomposites.
Room-Temperature Deformation Behavior in the Localized Regions W-80vol%Cu Composite
Authors: Hanado H. , Hiraoka Yutaka
Published: March 2009

Room-temperature deformation behavior in the localized regions of W-80vol%Cu
composite was investigated in this study. Plastic strain of about 10 % was added to the specimen at
room temperature using a three-point bend testing machine. Then deformation behavior in a
localized region was investigated using a high-magnification SEM photograph before and after
deformation.
Results are summarized as follow. (1) In a localized region near a large pore, heterogeneous
deformation had occurred as expected. (2) In a region apart from a pore, mostly homogeneous
deformation occurred but occasionally heterogeneous deformation occurred.
Fabrication and Microanalysis of Nano-Structured CuOX-CeO2 Catalysts for CO Oxidation Reaction
Authors: Šmíd Bretislav , Mori Toshiyuki , Takahashi M. , Ou Ding Rong , Matolín V. , Matolínova Iva
Published: March 2009

Carbon monoxide (CO) is a significant air pollutant produced in incomplete oxidation of
carbon in combustion. From the viewpoint of environmental protection, it is important that the
concentration of CO gas is lowered in air. Catalysis is proving to be an effective route for removing
this pollutant. Therefore, a design of nano-structured catalysts with high efficiency is required. In the
present work, we focus on a development of nano-size CuOx-CeO2 catalysts for CO oxidation
reaction. To prepare nano-structured Cu loaded CeO2 catalysts, a combined method of the
conventional impregnation and ammonium carbonate co-precipitation was examined. Morphology,
crystal phase and surface structure of prepared catalysts were characterized using High-Resolution
Transmission Electron Microscopy (HRTEM), Scanning Electron Microscopy (SEM) and Powder
X-ray Diffraction (XRD). Catalytic properties of CuOx-CeO2 for CO oxidation were investigated in
gas flow reactor system under atmospheric pressure and compared with copper oxide loaded zinc
oxide. We expected that nano-structured CuOx-CeO2 catalysts could be used for removing CO
produced in a wet reforming reaction of fuel cell applications.
Hydrogen Detection by a GaAs-Based Transistor with a Palladium (Pd) Thin Film Gate Structure
Authors: Hung C.W. , Cheng S.Y. , Lin Kun Wei , Tsai Y.Y. , Lai P.H. , Fu S.I. , Liu W.C.
Published: March 2009

By combining the advantages of a catalytic palladium (Pd thin film) with a
high-performance GaAs-based transistor, an interesting hydrogen sensor is fabricated and
demonstrated. For the studied device, a 50 Å undoped GaAs cap layer is grown to prevent the
Al0.24Ga0.76As Schottky layer from oxidizing and to suppress the Fermi level pinning effect. The
sensing mechanism can be described as the dissociation of hydrogen molecules and the polarization
of hydrogen atoms. The drain-source variation ΔIDS is caused by the polarization of a dipolar layer
resulting in the modulation of the gate potential and carrier density level. Experimentally, a high
hydrogen detection sensitivity SJ value of 275.8 mA/mm-ppm H2/air can be obtained under the
14ppm H2/air gas. Even under a very low hydrogen concentration (≤4.3 ppm H2/air) at 303K, the
considerable current variation can be observed. Moreover, the fast hydrogen response is found.
Therefore, the studied device reveals the promise for high-performance hydrogen sensor
applications.