bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Deformation Temperature on the Hot Ductility of Non-Oriented Electrical Steels
Authors: García  S. Edgar , Treviño L. E. , Salinas-Rodríguez Armando
Published: March 2009

The hot tensile ductility of solution treated Si-Al electrical steels was investigated at
temperatures between 850 and 1150 °C. Samples for mechanical testing were obtained from
continuous cast thin slabs and hot rolled strips. A continuous decrease in ductility was observed up
to about 1000 °C. After that, the ductility was recovered in strip samples while in slab samples the
ductility remained constant at RA<10%. This behavior was associated with the presence of large
quantities of undissolved AlN particles formed during slow cooling of the slab. In the case of strip
specimens, where the starting slab is not cooled to room temperature, the 1000 °C ductility
minimum was attributed to strain localization at grain boundary nucleated ferrite grains. Rapid
nucleation and growth of microvoids at AlN particles formed during cooling to test temperatures in
the vicinity of Ae3 resulted in intergranular tensile failure by microvoid coalescence.
Effect of Plastic Deformation on the Isothermal FCC/HCP Phase Transformation during Aging of Co-27Cr-5Mo-0.05C Alloy
Authors: Mani-Medrano A. , Salinas-Rodríguez Armando
Published: March 2009

The effects of tensile deformation on the amount of hcp phase formed during a 3 hour isothermal aging at 800 °C is studied using in-situ X-ray diffraction and scanning electron microscopy. It is shown that the start of the isothermal martensitic transformation during aging of this material is delayed by prior plastic deformation. Nevertheless, the total amount of hcp phase present in the microstructure at the beginning of aging increases at a continuously decreasing rate due to stress-assisted transformation. This behavior is attributed to the relieving of internal stresses produced by plastic deformation prior to aging. Finally, during the last stage of aging, the amount of hcp phase in the microstructure increases as a result of isothermal martensitic transformation. It is suggested that the presence of mechanically-induced hcp phase during aging inhibits the thermally activated nucleation process that leads to the isothermal martensitic transformation.
Self-Affine Quasi-Static Fracture of Soda-Lime Glass
Authors: Guerra-Amaro Claus , Hinojosa M. , Reyes-Melo E. , González V.
Published: March 2009

In the present work we discuss the self-affine properties of the fracture surfaces of sodalime glass obtained under quasi-static conditions. The fracture surfaces are generated using a threepoint bending system in normal room conditions and under high humidity conditions. The surfaces were recorded both by Scanning Electron Microscopy and Atomic Force Microscopy, and their selfaffine properties are characterized using the Variable Bandwidth method. For both conditions it is observed that the major part of the fracture surface is occupied by the mirror zone. On the other hand, the self-affine analysis reveals that for both conditions the roughness exponent has values centred at around 0.58 with moderate dispersion, in agreement with previous results. Our findings support the hypothesis of the existence of a characteristic roughness exponent for quasi-static fracture with a value that is significantly lower than the value of 0.8 reported for rapid fracture conditions.
Thermal Analysis and Microstructure Comparison Between A356 Aluminum Alloy and A356/15%vol. SiCP Cast Composite Modified with Strontium
Authors: Trejo E. E. , García-Hinojosa J.A. , Surappa M.K. , Rodríguez E.
Published: March 2009

A study of the effect of strontium on some solidification parameters, such as eutectic
nucleation temperature, eutectic growth temperature, eutectic undercooling temperature and eutectic
undercooling time, has been carried out using thermal analysis for a composite reinforced with 15
vol. % SiCP and, for comparison, for an A356 aluminum alloy. The composite is prepared by the
melt stirring technique with a SiC particle size of 38 μm. Thermal analysis results show that the
presence of SiCP in the unmodified A356 aluminum alloy increases the eutectic growth temperature
(TE) and the eutectic nucleation temperature (TNucl); on the contrary, SiCP decreases the eutectic
undercooling temperature (θ) and the eutectic undercooling time (tE). These phenomena suggest
that SiC particles give favorable conditions for the growth of eutectic silicon. On the other hand, the
modification with strontium of the composite material, although showing basically the same effect
on the eutectic parameters as the one described for the A356 aluminum alloy, brings about certain
differences due to the presence of the SiC particles. Microstructural analysis shows that the eutectic
structures in the composite are coarser than those of the matrix alloy and they do not have the
classic fibrous eutectic shape obtained in the matrix alloy. For the matrix alloy, when the Sr
concentration increases beyond the quantity required to obtain a well-modified structure, the
eutectic structure suffers a gradual coarsening or a reversion from fine fibrous silicon to coarser
silicon; subsequently, when the Sr concentration is higher than 0.068%, Al2Si2Sr particles are
produced. In the composite material there is also a gradual coarsening of the eutectic structure,
although the appearance of Al2Si2Sr particles is just seen when the Sr concentration reaches
0.106%.
WC / Stainless Steel Joints Produced by Direct Diffusion Bonding Using a Ni-Foil Interlayer
Authors: Lemus-Ruiz José , Ávila-Castillo J.J. , García-Estrada R.
Published: March 2009

Cemented tungsten carbides are industrially one of the most used composite materials as
cutting tools, wear parts and replacements of standard materials for tools, dies and machine
components. This work focuses on various aspects of diffusion bonding of tungsten carbide to AISI
304 stainless steel using a Ni-foil interlayer. WC/Ni/AISI 304 combinations were diffusion bonded
at 1000°C using different holding times under argon atmosphere. The microstructure
characterization of the resulting interfaces was carried out by SEM and EPMA. The results show
that successful joining between WC and AISI 304 steel is achieved by the formation of a diffusion
zone at both ends of the Ni foil. All WC/Ni/AISI 304 samples have been joined with no severe
interfacial cracking or porosity at the interface. The joint strength is determined by four-point
bending testing, a maximum of 210 MPa for samples joined at 1000 °C for 60 minutes has been
achieved. These results indicate that there is a strong relationship between the thickness of the
diffusion interface and the mechanical strength of the joints.
Austenite-Ferrite Transformation in Non-Oriented Electrical Steels
Authors: Díaz Barriga-Castro Enrique , Salinas-Rodríguez Armando , Nava-Vázquez Enrique
Published: March 2009

The aim of the present work is to determine the austenite to ferrite transformation
temperatures in a Si-Al non-oriented electrical steel. Critical transformation temperatures on
heating and cooling are determined using an in-situ X-ray diffraction technique where the specimen
is heated or cooled in a stepwise manner. The transformation temperatures are estimated from
changes in the intensities of the (110)α and (111)γ peaks as a function of temperature. The time
evolution of the microstructure resulting from isothermal heat treatments at temperatures between
800 and 1000 °C applied after cooling from 1050 °C is followed by quantitative metallography on
samples quenched into water. The results show that, on cooling, formation of ferrite starts at about
950 °C and ends at 790 °C, indicating a strong effect of Si and Al on the austenite to ferrite and
eutectoid transformations. These results suggest that the low tensile ductility exhibited by this
material at temperatures near 1000 °C can be attributed to strain localization in strain-induced
ferrite formed at temperatures as high as 1025 °C.
Self-Affine Analysis of Fractures Surfaces of an Aluminum Alloy Using Fractographic Techniques
Authors: Hinojosa M. , Morales Edgar I. , Mohamed N.
Published: March 2009

We report the self-affine analysis on fracture surfaces of an A319-type aluminum alloy with different modification and refinement treatments, broken both in Charpy impact and cyclic impulse tests. The in-plane and out-of-plane Hurst exponent as well as the correlation length are obtained using quantitative fractographic techniques. It is found that the Hurst exponent, ζ, has a value of about 0.8 and is not influenced neither by the crack propagation modes nor by the microstructural condition. The self-affine correlation length is found to be related to the grain size resulting from the refining and modifying treatments applied to the alloy.
Underground Space Construction by Explosive Loading in a Borehole
Authors: Tateyama Kazuyoshi , Itoh Shigeru , Maehara Hironori
Published: March 2009

In cases where a borehole has been dug in the ground and subjected to an explosive
load, the soil around the borehole wall will be abruptly compressed and a cavity will then be created
in the portion of the ground that is surrounded by the compressed soil wall. When this procedure
is applied to the construction of tunnels or foundations, underground spaces can be created with
minimum mucking and a thinner lining. The authors carried out some laboratory experiments in
which small boreholes were expanded by blasting. The results of the experiments increase our
knowledge and elevate the possibility of applying this procedure to underground space construction.
Research on Sessile Organism Removal from Metal Using the Underwater Shock Wave
Authors: Takemoto Ayumi , Watanabe Toshiaki , Iyama Hirofumi , Itoh Shigeru
Published: March 2009

The sessile organism of the oyster and the barnacle, etc. causes friction between the surface
of the ship and the water. Friction causes the deterioration of fuel cost. In addition, dry dock operation
with putting the ship on the land or the diving operation, are needed for the removal of the sessile
organism. These works require a very high cost. Various techniques for reducing friction resistance
have been proposed. On the other hand, the method for the practical use is not popular still now.
Authors tried to perform an experiment to remove the sessile organism on surface of the metal by
using the underwater shock wave.
The Study about “Cullet” Generation Technique and Application for Recycling System by Using Underwater Shockwaves
Authors: Kawabe S. , Sakamoto Hidetoshi , Himeno Masahiro , Ono T. , Itoh Shigeru
Published: March 2009

The high-speed fracture mechanism of glass bottles by using underwater shockwave and
the recycling process by crushing the glass bottles were discussed. The proposed crushing process
of the glass bottles can decrease the recycle cost by generating small fragments called "Cullet" and
by executing the washing process at the same time as the crushing process. In this study, the
relations between the "Cullet" sizes and various explosive conditions, that is, the distance from
explosive, the amount, the velocity and the shapes of explosive, were clarified by using beer bottles,
and the influence of the serial and concentric arrangements of two or more bottles on "cullet" sizes
were examined. Moreover the behaviors of the underwater shockwave were observed by framing
photograph method, shadowgraph method, illumination photography method and the FEM
simulation was executed in order to make clear the high speed fracture mechanism.
Basic Study for Crushing of Ice by Underwater Shock Wave
Authors: Watanabe Toshiaki , Maehara Hironori , Itoh Shigeru
Published: March 2009

The aim of this study is to confirm a new technique that can crush ice by underwater shock wave
generated by underwater explosion of explosive. Damage caused by ice occurs in the cold regions at
different circumstances. For example, the problems such as accretion of ice on the drainage of snow
melting system, on the ship and on farm lands. The solution for such problems is to use a method of
heating. As the necessary quantity of heat is enormous and the problem of global warming exists, the
dynamic way of solving is desirable. At first, we carried out experiments using detonating cord and ice block.
The process of propagation of shock wave in ice was observed by using the high-speed camera.
Micro Structural Studies On Explosively Clad Cu/Ss, Br/Ss and Al/Ss Plates
Authors: Tamilchelvan P. , Raghukandan Krishnamorthy , Meikandan N. , Sivakumar K.
Published: March 2009

The paper deals with detailed studies on the bond zone morphology of Cu / Ss, Br / Ss, Al / Ss weld combinations of explosive welds. The study becomes significant in view of the importance and wide applicability of these materials in bimetal industry. Explosive welding is a high-energy rate fabrication technique and is increasingly employed to provide sound metallurgical bonding between similar and dissimilar metals with widely varied properties. In this study for the same explosive loading conditions, the different types of bonds obtainable at the interface for three combinations of materials have been investigated. The bond zones showed characteristic features, typical of the explosive welding process. Complex patterns of plastic flow and formation of solidified melt areas were revealed at the interface.
Dynamic Response of a Steel Pipe to Internal Blast Loading
Authors: Simangunsong Ganda M. , Kubota Shiro , Saburi Tei , Katoh Katsumi , Yoshino S. , Wada Yuji , Ogata Yuji
Published: March 2009

To design a cylindrically-shape explosion container, the experiment of a high explosive
charge detonating in a steel pipe has been performed. The charges, composition C4, were positioned
at the geometrical centre of the steel pipe. Two kinds of measurements were performed on the steel
pipe: circumferential strain and outside diameter. The strain-time history shows that the pipe structure
vibrates and the vibration is decaying. It has been reported that this type of response is explained as
the mechanism of strain growth, and this problem is taken up to verify computer simulation in this
study. This simulation code could be strong tool to estimate the geometries of the explosion container.
The relationship among the pipe parameter, explosive charge and pipe’s final deformation is proposed
as practical guidance for predicting radius and thickness of the pipe correspond to the level of internal
blast loading.
Utilization of Technology of Explosive Welding at Development of Multilayer Ballistic Resistant Materials
Authors: Nesvadba Peter , Rolc Stanislav
Published: March 2009

The technology of explosive welding (EXW) was used for development of metallic
multilayer ballistic resistant materials. Explosive cladded two or multilayer materials serve as final
product or as semi-finished product for further processing, e.g. rolling. The objective is to create
material with sufficient ballistic resistance at relatively small thickness of the resulting multilayer
structure. Under retaining the weight of armoured vehicle its ballistic resistance can be increased or,
under retaining its existing ballistic resistance the weight can be reduced. Resulting material should
be producible of commercially available metallic materials using common technologies, especially
the technology of roll welding (ROW). For the primary tests it is possible to model the resulting
structure by means of EXW and some its properties can be verified in the initial stage of research of
the multilayer structure (e.g. tests of heat processing, verification of diffusion processes, behaviour
under various types of load, verification of ballistic resistance and other technological tests).
Subsequently, production can start of large semi-finished products by means of ROW technology.
Effective preparation is possible of the samples of multilayer materials by means of EXW
technology in various material combinations - armour steel, tool steel and interlayer based on nickel,
nickel alloys etc.
Investigation of Jet Formation with Overdriven Detonation in High Density Explosive
Authors: Kato Hisaatsu , Murata Kenji , Itoh Shigeru , Kato Yukio
Published: March 2009

To increase largely the performance of shaped charge, it is required to generate detonation velocity
much higher than CJ velocity or detonation pressure much higher than CJ pressure of existing high
explosives. One solution is the application of overdriven detonation phenomena. In this study, the
effects of overdriven detonation in tungsten loaded high density explosive on the performance of
shaped charge were demonstrated by experiments and numerical simulation. Sample shaped charge
was composed of the inner layer tungsten loaded high density PBX and outer layer high velocity
PBX. Concentration of tungsten powder in high density PBX was varied from 20 to 60% in mass.
The pressure of overdriven detonation in inner layer PBX was measured by PMMA gauge, and was
shown to be higher than 50GPa. The experimental results showed that the initial jet velocity and jet
penetration velocity in target plates were largely increased by the effects of the overdriven detonation
in tungsten loaded high density PBX.
Vacuum Breakdown Behavior of CuWCr Composites
Authors: Xiao Peng , Fan Zhi Kang
Published: March 2009

The Cu20W70Cr10 composites were fabricated by two methods which are the conventional powder metallurgy, and mechanical alloying to prepare WCr compound powders, followed by sintering and infiltration. The erosion behavior of CuWCr composites under breakdown was investigated. The surfaces of the composites before and after erosion and the mechanism of arc erosion were studied by scanning electron microscopy. The results show that the CuWCr composites prepared by mechanical alloying have superfine microstructure, uniform composition and high density, thus result in good characteristics of diffusing arcs and arc eroding endurance. Arc erosion zones are dispersive and uniform on the surfaces with some flat eroding pits. The Cu20W70Cr10 composites have excellent electrical properties such as high breakdown voltage, low chopping current and long arc life.
Deposition of ISZO Films on Polymer Substrate Using Two Cathodes
Authors: Lee Jung Rak , Lee Dong Yeop , Kim Do Geun , Lee Gun Hwan , Song Pung Keun
Published: March 2009

The electrical, optical and mechanical properties were investigated for the In-Sn-Zn-O
films deposited using ITO and ZnO targets, without substrate heating. Three types of ITO target,
which are 90wt.% In2O3 : 10wt.% SnO2, 93wt.% In2O3 : 7wt.% SnO2, and 95wt.% In2O3 : 5wt.%
SnO2, were used. The power of DC cathode equipped ITO target was fixed at 70W and the power of
RF cathode equipped ZnO target was changed from 20W to 60W. The lowest resistivity (2.95x10-4
2cm) was obtained for the In-Sn-Zn-O films deposited under DC power of 70W of ITO (93wt.%
In2O3 : SnO2 7wt.%) and RF power of 40W of ZnO target. It is confirmed that surface uniformity,
electrical property, and mechanical durability were improved by introduction of Zn atom for all the
ITO targets.
A Study on the SiC/Al Composites Fabricated by Pressureless Infiltration
Authors: Sang Ke Zheng , Wan Chun Feng
Published: March 2009

SiC/Al composites with high volume fraction of SiC were prepared at 1150°C by pressureless infiltration. The volume fraction of SiC was increased by decreasing the amount of starch in the green body. Both the microstructure and the strength of the composites were investigated. The results showed that the strength decreased with the increasing of the particle size and volume fraction of SiC. It was suggested that the interface between the SiC particles, which were not sintered, make of the defects in the composites. The defects led to the decreasing of the strength with increasing of the volume fraction of SiC.
Photocatalytic Cr(VI) Reduction by Anodized TiO2
Authors: Yoon Jae Kyung , Shim Eun Jung , Ha Jin Wook , Joo Hyun Ku
Published: March 2009

In this study, immobilized nanotubular TiO2 is used to reduce toxic Cr(VI) to non toxic
Cr(III) in aqueous solution under UV irradiation. To overcome the limitation of powder TiO2, a novel
technique of immobilization based on anodization was applied and investigated under various
experimental conditions. Among the samples tested under same anodizing condition, the nanotubular
TiO2 annealed at 450 oC and 550 oC showed higher reduction efficiencies of Cr(VI). In addition, the
surface characterizations (zeta potential, XRD and SEM) of these samples proved that the Cr(VI)
reduction efficiency was higher under acidic conditions and at a lower annealing temperature.
Through this study, it was concluded that anodized TiO2 has the potential to be useful technology for
environmental remediation as well as hydrogen production in water.
Oil Removal Using Diethyl Ether Extracted and Ground Kenaf Core
Authors: Lee Beom Goo , Lee Hyun Jong , Shin Dae Yong , Jeong Yeon Ho , Jin Cheng Wu , Cho Dong Ha , Lee Kang Yol , Kim Dong Eun , Kang Wie Soo , Goh Young Gyun , Hwang Byung Ho
Published: March 2009

Kenaf core was tested for its ability to sorb diesel oil from the pure diesel oil bath and the diesel oil containing water bath after extracting with diethyl ether to remove wax from fiber surface, grinding to disrupt lumen structure and presoaking in water. Oil sorption capacity was the highest as 8.0 g/g in diethyl ether extracted fiber in oil bath, and the lowest as 1.3 g/g in water soaked kenaf core in water bath. Diesel oil sorption capacity was much higher in oil bath than in water bath. In diethyl ether extraction the diesel oil sorption capacity was not changed much in kenaf core, compared to that of control. Also, even after grinding and passing through 20 mesh screen (0.86mm) the diesel oil sorption capacity was almost same. When kenaf core was presoaked in water the oil sorption capacity was decreased to about half of control as 1.3g/g in water bath. Grinding, extracting and water presoaking all contributed to the changes in oil sorption capacity. The results show that if in lignocelluloscic fiber like kenaf core the fiber structure is not disrupted during processing and the intact lumen structure can be kept, the oil sorption capacity may not be affected much by physical and chemical changes.
Fabrication of Porous β-Tricalcium Phosphate with Collagen Composite Materials
Authors: Igarashi Yuki , Matsushita Junichi
Published: March 2009

Biomaterials have been developed and used for bone grafting. Here, we study a fabrication
of composite for bone tissue engineering by combining tricalcium phosphate and collagen. This
tricalcium phosphate and collagen composite material may be applicable for use as a bone substitute.
The β-tricalcium phosphate (β-TCP) is the one of the most investigated biomaterials due to its
biocompatibility and good bioactivity. The β-TCP is used in a filling purpose to the bone defect
region such as bone fractures. It is known that β-TCP substitutes it for a self bone in the body. The
ingredient of the real bone is made of hydroxyapatite and collagen. In this study, the purpose was at
giving the mechanical property and biological property which were near to a bone with β-TCP and
collagen this time. We evaluate what kind of action collagen addition.
Absorption and Preservation of Bentonite Containing Smectite
Authors: Matsushita Junichi , Yang Seong Ho , Hwang Geum Chan
Published: March 2009

The Na-bentonite with contained smectite was fabricated in order to observe their
absorption and preservation about water. Absorption of fabricated specimens in the water and
preservation of absorbed samples in the drying machine at 323 K was measured. It was obtained that
absorption had been decreasing with increasing smectite. Absorption of As-received Na-bentonite
was higher than absorption of As-received smectite. The preservation has been also decreased with
increasing smectite was obtained. Na-bentonite with contained smectite were investigated the good
absorption and preservation when the Na-bentonite containing smectite 5 mass %.
Effect of Different Chemical and Physical Characteristic Having Lignocellulosic Fibers on Heavy Metal Ion Removal from Auqueous Solution
Authors: Lee Hyun Jong , Lee Beom Goo , Shin Dae Yong , Park Heon
Published: March 2009

In this study lignocellulosic fibers, such as kenaf bast, kenaf core, sugar cane bagasse,
cotton, coconut coir, and spruce, which are environment friendly natural materials, were tested for
their ability to remove copper, nickel and zinc ions from aqueous solutions. The fibers were analyzed
for Klason lignin content, water sorption capacity and dry volume. The fiber with the highest level of
heavy metal removal in the separate and mixed solution was kenaf bast.. In the mixed solution kenaf
bast, sugar cane bagasse and cotton removed more copper and nickel ion than in the separate solution,
and the amounts of removed heavy metal ions were changed in some lignocellulosic fibers, compared
to those of the separate solution. In the mixed solution heavy metal ions may compete with one
another for sorption sites on the surface of lignocellusic fiber. In kenaf bast to remove heavy metal
ions most, Klason lignin content was the second lowest, and water sorption and dry volume were the
lowest in all tested lignocellulosic fibers. It showed that removal of heavy metal ions does not
correlate with any chemical and physical factors, but may be affected by the cell wall structure of
lignocellulosic fibers and how many free phenolic groups in lignin, which are considered as the heavy
metal ion binding site, are exposed on the surface of fibers. Cotton, with about 1% Klason lignin, was
very low in heavy metal ion removal, while all other fibers containing greater than about 10% lignin
did remove heavy metal ions. It showed that even the lignin content of lignocellulosic fibers does not
correlate with heavy metal ion removal but lignin does play a role in heavy metal ion removal.
An Experimental Study of the Characteristics of Environment-Friendly Construction Materials by Recycling Sewage Sludge Ash
Authors: Lee Jae Ik , Jo Byung Wan , Yoo Yeong Seok , Cheon Kyeong Ho
Published: March 2009

As a basic stage for developing new construction material utilizing sewage
sludge ash, this study is identified by specific material characteristics through XRD, SEM,
uniaxial compressive strength, porosity, and the drying shrinkage by manufacturing mortar
with sewage sludge ash. The average drying shrinkage of sewage sludge ash mortar aged 7
days showed 88% of the strain of the one aged 28 days. The porosity of sewage sludge ash
mortar was about 7~10%. The more quick lime and blast furnace slag were added, the less
porosity appeared.
Effect of Impurities on Formation of Pores in Porous Alumina during Unidirectional Solidification
Authors: Ueno Shunkichi , Lin Li Ming , Nakajima Hideo
Published: March 2009

A porous alumina with cylindrical pores was fabricated by unidirectional solidification
under hydrogen gas flow (0.1 MPa) using alumina feed rods doped with silica, calcia or sodium oxide.
The additives in the feed rods strongly affect the formation of porous structure during the
solidification. The porosity increases with increasing silica content. The increase of porosity is
enhanced by further addition of sodium oxide. The addition of calcia to the feed rod is effective on the
homogenization of pore distribution. The porous alumina with 1mol%CaO and 20mol%SiO2
additives showed 50% porosity and homogeneous pores distribution.
Zeolite Synthesis Using Sewage Sludge by Molten-Salt Method
Authors: Yoo Yeong Seok , Cheon Kyeong Ho , Lee Jae Ik , Kim Beom Suk , Shin Woo Seob , Seo Gyu Tae
Published: March 2009

This study was conducted to synthesize zeolitic materials using sewage sludge by molten-salt method the effective method was investigate to reduce the thermal treatment time by adding zeolite seed and excessive sodium hydroxide. To synthesis zeolitic materials, sewage sludge was used as Si and Al sources, also Na2SO4 and NaOH were added as stabilizer and mineralizer respectively. Sewage sludge was prepared by calcination at 550°C/3hr to remove organic materials. As a result of thermal treatment at 950°C for 6~24hrs, more than 18 hours was required to synthesize zeolitic materials without adding zeolite seed. On the other hand, it is observed that hydroxyl-sodalite was synthesized in 9 hours thermal treatment and Na-P1 also in 12 hours when zeolite seed was added, but no other differences were observed when excessive sodium hydroxide was added. Consequently, the overall reaction time required could be reduced by adding zeolite seed and changing thermal treatment temperature. However, addition of NaOH does not show significant effect on the reduction of zeolite synthesis time.
Treatment Performance of Photocatalysis/H2O2/Metal Membrane Process for Organics Removal
Authors: Jung Jong Tae , Kim Jong Oh , Choi Won Youl
Published: March 2009

The objective of this study is to evaluate the performance of photocatalysis/hydrogen
peroxide/metal membrane system. Metal membrane for the separation of TiO2 particles was used in
an experiment and nominal pore size is 0.5 μm. Hydrogen peroxide was tested as oxidants. The
removal efficiency of CODCr and color for initial hydrogen peroxide concentration increases rapidly
with an increase in the hydrogen peroxide concentration up to 50 mg/L. The removal efficiency of
of CODCr and color for 50 mg/L of initial hydrogen peroxide concentration was about 95 % and
98 %, respectively. However, the addition of hydrogen peroxide over 50 mg/L inhibits the system
efficiency. The addition of hydrogen peroxide in UV/TiO2 system enhanced removal efficiency of
CODCr and color compared to no addition of hydrogen peroxide. This may be ascribed to capture
the electrons ejected from TiO2 and to produce OH radicals. The application of metal membrane in
UV/ TiO2/H2O2 system enhanced removal efficiency of CODCr and color due to the adsorption of
metal membrane surface as well as the production of OH radical. In application of metal membrane
with nominal pore size 0.5 μm, TiO2 particles were effectively separated from the treated water by
metal membrane rejection. Photocatalytic metal membrane was much smaller resistance than these
of humic acid, TiO2 and humic acid/ TiO2 due to humic acid degradation of photocatalytic reaction.
Structural and Electrical Properties of Vanadium Tungsten Oxide Thin Films Grown on Pt/TiO2/SiO2/Si Substrates
Authors: Nam Sung Pill , Lee Sung Gap , Lee Young Hie
Published: March 2009

The V1.9W0.1O5 thin films deposited on Pt/Ti/SiO2/Si substrates by RF sputtering method
exhibited fairly good TCR and dielectric properties. It was found that film crystallinity, dielectric
properties, and TCR properties were strongly dependent upon the annealing temperature. The
dielectric constants of the V1.9W0.1O5 thin films annealed at 300°C were 37.7, with a dielectric loss of
2.535, respectively. Also, the TCR values of the V1.9W0.1O5 thin films annealed at 300°C were about
-3.7%/K.
Synthesis of Nickel Coated Gadolinia Doped Ceria Nanopowder by Microwave Radiation
Authors: Lim Jong Min , Kim Sang Woo
Published: March 2009

Nickel coated gadolinium doped ceria (GDC) powder was synthesized by microwave
radiation and combustion. For the synthesis, the precipitates of gadolinium cerium oxycarbonate
hydrate (GdxCe2-xO(CO3)2·H2O) were formed by a microwave radiated reaction between cerium
nitrate (Ce(NO3)3.6H2O) and gadolinium nitrate (Gd(NO3)3.6H2O) and urea (CO(NH2)2), then nickel
coatings on the gadolinium cerium oxycarbonate hydrate were performed by further microwave
reaction between nickel chloride and urea. The shape and size of the gadolinium cerium oxycarbonate
hydrate particles were critically dependent on aging time during microwave radiation. The irregular
particles were transformed to rod shape particles with well-crystallized with increasing aging time to
40 min at 70 - 80°C because of the gradual decomposition of urea during microwave radiation. Small
nickel precursor particles were homogeneously coated on the gadolinium cerium oxycarbonate
hydrate particles with rod shape with aid of microwave radiation at 80 °C for 40 min. As a result, the
nickel coated GDC nanopowders were sucessfully produced by the microwave radiation synthesis
and further microwave combusted at 450°C for 20 min.
Analysis of Cell Toxic Experiments in New Synthetic Compounds from Nano-Scaled Collagen
Authors: Kim Jong Hae , Choi Won Chul
Published: March 2009

In this paper, we consider the analysis of grinding collagen and mathematical function
from the cell toxic experiments using interpolation method in new synthetic organic compounds. The
extracted collagens and functional cosmetics such as mask, whitening, and serum from collagen are
measured with a SEM (Scanning Electron Microscope) and a light-microscope. Also, interpolation
method is used for analysis of cell toxic experiments in new synthetic compounds from collagens.
The obtained mathematical function can help to provide analytic approach on various toxic
substances at different densities. The results can be used as basic data on development for synthesis of
new marine functional materials and their derivatives.
Preparation and Chracterization of Nanocomposites of Polyamide 6/Brazilian Clay with Different Organic Modifiers
Authors: Souza Michelle A. , Larocca Nelson M. , Araújo Edcleide Maria , Pessan Luiz Antonio
Published: March 2009

Nanocomposites of PA6 / organoclay at different concentration were prepared via melt intercalation method using a corotating twin screw extruder. The composites were prepared with Brazilian clay that was treated with different modifiers based on quaternary ammonium salts to obtain three types of organoclays. After extrusion the mixtures were injection molded into specimens that were tested to obtain the properties of tensile strength, notched izod impact and heat deflection temperature. The structure and morphology of the nanocomposites were characterized by x-rays diffraction (XRD) and transmission electron microscopy (TEM). The results showed that the modifier “dodigen” which promoted the intermediate expansion of the bentonite clay within the three salts used for the modification of the clay affects more significantly the mechanical properties, HDT and morphology of the polyamide 6 due to the higher level of exfoliation observed in these systems compared to the others modifiers. The improvement of the properties was correlated to the level of exfoliation/intercalation obtained which depends on the process technique used, surface treatment of the Brazilian clays with organic salts and interaction between polymer and clay.
Investigation of the Stress Fields Around a Fatigue Crack in Aluminium Alloy 5091
Authors: Rahman M. , Fitzpatrick Michael E. , Edwards Lyndon , Pratihar S. , Peel Matthew J. , Steuwer Axel , Buslaps Thomas
Published: March 2009

There have been many theoretical studies to predict the stress fields around the tip of a
growing fatigue crack. However, until recently the highly-localized, small scale nature of the
stresses has meant that direct measurement has not been possible. With the current generation of
synchrotron X-ray sources, sub-millimetre sampling dimensions are now possible, and it has
become possible to evaluate directly the stresses at the tip of a fatigue crack and to see how the
stresses evolve as the result of an overload, for example.
In this paper we present results of synchrotron X-ray diffraction analysis of the stress fields
around a fatigue crack in aluminium alloy 5091 (Al-Mg-Li-C-O); this is a dispersion-strengthened
alloy with a fine grain size, which makes it ideal for such experiments. Compact tension (CT)
specimens were prepared with constant amplitude fatigue loading. The energy dispersive X-ray
diffraction (EDXRD) technique was used for measuring strains around the crack tip along the mid
thickness of the specimen under in-situ loading. The measurement was carried out at the ESRF
(European Synchrotron Radiation Facility), Grenoble, France on the ID15A beam line. The
experimental crack tip stresses have been compared with the analytical fracture mechanics solution.
Stored Energy of Plastic and Elastic Origin and Recrystallization
Authors: Wierzbanowski Krzysztof , Baczmanski Andrzej , Tarasiuk Jacek , Lipiński Paul , Lodini Alain
Published: March 2009

Stored energy is generally considered as a main driving force of recrystallization process.
After plastic deformation a high dislocation density and residual stress field remain in a material.
Both quantities are at the origin of the stored energy and we call them as the “plastic” and “elastic”
parts of this energy. Their orientation distributions can be determined using diffraction and
deformation models. Both components of the stored energy are studied in the present work. Their
distributions and characteristics are studied for f.c.c. and b.c.c. materials.
Influence of the Welding Sequence on Residual Stresses in Laser Welded T-Joints of an Airframe Aluminium Alloy
Authors: Machold Winulf , Staron Peter , Bayraktar Funda S. , Riekehr Stefan , Koçak Mustafa , Schreyer Andreas
Published: March 2009

The effect of different welding sequences between a 4.5 mm thick AA 6156 T6 base
plate and a 2 mm thick AA 6013 T6 clip – resembling a skin-clip joint of an airframe – using a
3.3 kW Nd:YAG laser is investigated. Under cyclic loading the breakdown of such T-joints happens
at one end of the clip, which is due to local residual stress concentrations. Recent measurements
indicated that tensile stresses could be lower at the run-in than at the run-out locations. For a deeper
investigation of this effect sheets with different welding sequences were produced. One welding
sequence was made with two starting points in the centre, and a second with starting points at the
clip ends. Temperature measurements were made using thermocouples to verify the heat conditions
for a finite element simulation of the welding process, which is used for predictions of the residual
stress distribution. Actual values of the residual stress fields were determined by neutron
diffraction. The influences of the welding sequence on the measured temperatures and the residual
stresses are discussed.
SXRD Measurements of Residual Stresses in Sintered Diamond–Cobalt Composites
Authors: Crostack H.A. , Selvadurai-Lassl Ursula , Fischer Gottfried , Rothkirch André
Published: March 2009

Diamond-cobalt composites are used for cutting tools. Residual stress after manufacture
can reduce the lifetime of such composite cutting tools and, hence, the stress state needs to be well
understood. Within this study, stress measurements on a cobalt diamond composite were made by
SXRD to deduce stress states in the cobalt matrix using the (222) reflection. The application of
different apertures allowed the investigation of stress in small areas of cobalt surrounding a
diamond and in areas at different distances to a diamond. In the areas adjacent to the diamond
increased residual stresses were found in the cobalt matrix. Furthermore, approximations for radial
and tangential residual stresses have been derived which show to be different.
Position Resolved Residual Stress Determination in Alumina-Zirconia Multilayered Ceramics
Authors: Maier Guenther A. , Keckes Jozef , Brechbuehl Jens , Guerault Hugues , Bermejo Raúl
Published: March 2009

Alumina-zirconia multilayered ceramics have been proposed as an alternative for the
design of structural ceramics with improved fracture toughness and strength reliability. During the
processing of these laminates, significant residual stresses may arise due to the thermal expansion
mismatch between adjacent layers. The correct evaluation of such stress distribution in the laminate
may determine its range of application. In this work, the residual stress state in a layered material
designed with five thick alumina layers of approximately 650 microns alternated with four thin
alumina-zirconia layers of approximately 140 microns was estimated using different methods. A
finite element analysis (FEM) was performed for stress evaluation in the bulk and an indentation
method and X-Ray diffraction to account for stresses at the surface. Experimental findings show a
constant stress distribution within the bulk for each layer, while at the surface stress position
dependence is observed in the alumina layers, being the maximum tensile stresses near the layer
interface. The accuracy of the results provided by each technique is discussed.
A New Optimization Algorithm for Inverse Analysis to Material Parameters
Authors: Lu Ying Hui , Wang Shui Lin , Jiang Hao
Published: March 2009

the inverse analysis to material parameters is often translated into an optimization for an
objective function, based on the correlation between the material parameters and the foregone
information. But mostly because of the non-linear correlation, a good optimization algorithm with
the capabilities to avoid being trapped by local optima is required during the process of
optimization. So the present paper proposes a new global optimization algorithm, which couples the
dynamic canonical descent algorithm and the improved Powell’s algorithm. The high efficiency of
the new algorithm is shown on four known problems classically for testing optimization algorithms
and finally, in the non-linear inverse analysis, the new algorithm is used for optimizing an objective
function to get material parameters rightly.
The Effect of Nonequilibrium Structure State on the Creep and Superplastic Behaviour of Materials
Authors: Myshlyaev M.M.
Published: March 2009

Mechanical behaviour at creep and superplasticity of coarse grain and monocrystalline
aluminum under torsion, of coarse grain molybdenum, of fine grain zinc alloy and amorphous
cobalt alloy under tension are discussed from unified positions. It is shown that realization of their
superplasticity requires fulfillment of structure-kinetic principle.
Research on the Accurate Control of Initial and Finishing Cooling Temperatures for X70 Pipeline Steels
Authors: Niu Tao , Yu Hao , Kang Yong Lin , Long Ming Jian
Published: March 2009

Different cooling parameters, including the initial cooling temperature, finishing cooling
temperature and cooling rate, have a significant effect on the final microstructures and properties for
pipeline steels. In present work, Gleeble-1500 thermal-mechanical simulator was used to investigate
the microstructural evolution of X70 pipeline steels under different cooling conditions, and the
microstructures obtained were analyzed using optical microscope and transmission electron
microscope. The experimental results showed that when the initial and finishing cooling temperatures
are controlled in the range of 740~760°C and 500~520°C respectively, the microstructure of X70
pipeline steels reveals a proper content (about 12%) of pre-eutectoid ferrite besides acicular ferrite
and M/A (Martensite/Austenite) island, which can guarantee an optimum combination of strength and
ductility. In contrast to the conventional way using CCT curve, this methodology shows a higher
accuracy and operability, and used in industrial production to achieve good effect.
Residual Stresses of Fiber-Reinforced Functionally Graded Composites
Authors: Ou Zhi Ying , Lei Dong Xia , Ma Lian Sheng
Published: March 2009

The residual stresses induced in fiber-reinforced functionally graded composites cooling
down from the processing temperature are determined with concentric cylinder model and
analytical solutions of inhomogeneous governing equations for displacement components, which
include particular solution and general solution of the corresponding homogeneous equations. The
analytical solutions presented here are general for power-law variations of the elastic moduli of the
functionally graded matrix. With a power exponent, analytical expressions for the residual stresses
of fiber-reinforced functionally graded composites can be obtained. By changing the power
exponent and the coefficient of the power terms, the solutions obtained here could be applied to
fiber-reinforced functionally graded composites with different properties. The results show that the
large difference exists between functionally graded composites and common-used composites
consisting of two phases of homogenous materials. The variation of matrix modulus and fiber
percentage have a great deal of effects on the residual stresses in functionally graded composites.
Research on Creep Constitutive Model of TC11 Titanium Alloy Based on RBFNN
Authors: Peng Xiang Hua , Luo Ying She , Zhou Jing Ye , Yu Min , Luo Tao
Published: March 2009

The paper is aimed to exploit a creep constitutive mode of TC11 titanium alloy based on
RBF neural network. Creep testing data of TC11 titanium alloy obtained under the same temperature
and different stress are considered as knowledge base and the characteristics of rheological forming
of materials and radial basis function neural network (RBFNN) are also combined when exploiting
the model. A part of data extracted from knowledge base is divided into two groups: one is learning
sample and the other testing sample, which are being performed training, learning and simulating.
Then predicting value is compared with the creep testing value and the theoretical value deduced by
primary model, which validates that the RBFNN model has higher precision and generalizing ability.
Effect of Zinc Content on the Ageing Behavior of Al-Zn-Mg-Cu-Li Alloys
Authors: Zhao Zhong Kui , Sun Qing Zhou , Zhang Pu Qing , Li Chang Long , Wang Xue Jiu , Chen Chang Qi
Published: March 2009

In this paper, Al-5.6Zn-2.8Mg-1.6Cu-0.24Cr-1.1Li, Al-8.0Zn-2.4Mg-2.4Cu-1.1Li-0.18Zr
and Al-11.8Zn-2.9Mg-2.8Cu-1.1Li-0.24Zr (in wt%) alloys were artificially aged at 80,100,120,140
and 160°C for different time, respectively. The ageing process, microstructure and hardness of
different alloys are investigated by Vickers hardness and transmission electron microscopy (TEM).
With the increment of zinc content, addition of Li to Al-Zn-Mg-Cu alloy containing high alloying
elements has little effect on the nucleation of precipitates, but the growth of precipitates has been
inhibited. Very fine precipitates with high density are formed during ageing due to the existence of
high alloying elements, which result in highly strengthening alloy. As the alloying content is too
high to exceed the solution saturation of matrix, coarse second phases are formed in grain boundary.
Simulation of the Processes of Aluminum Alloys Preforms and Semifinished Products Manufacture under Influence of Technological Heredity and Phase Transitions
Authors: Lisunets N.L. , Smirnov Oleg M. , Tsepin M.A.
Published: March 2009

In the present work, there are presented the results of experimental studies on the basis of
regression analysis and FEM-based modeling of the processes of aluminum alloys preforms and
semi-finished products manufacture including such widely known processes as cutting rolled
products by shear and thixotropic stamping (stamping of metal during crystallization). It is
investigated the influence of technological heredity created by variation of cant angles of end
surfaces and mono- and poly-directional pulling-down by shear in cutting rolled blanks on stability
of the process of subsequent longitudinal upsetting while producing preforms for bulk stamping. As
a result of studying the ways of eliminating such negative consequences of technological heredity
and increasing high-strength aluminum alloys technological plasticity, there is revealed the
possibility of using phase transitions (from solid to liquid state and back) while manufacturing
semifinished products in thixotropic conditions close to superplastic deformation.