bluuebunny/crossref_metadata_2025 huggingface dataset:
The Influence of PtFe and Nano Aluminium Particles on the Anticorrosive Performance of Waterborne Coating
Authors: Xue Li Li , Xu Li Kun , Li Qing Fen
Published: March 2009

In this paper, the anticorrosive performances of fastener coatings containing PTFE and/or
nano aluminum particles were investigated by using electrochemical impedance spectroscopy,
scanning electron microscope. The impedance spectroscopy was interpreted by means of analysis
equivalent electrical circuits. The coating capacitance of the films was monitored with the
immersion time to establish the water and ions permeability of these paint films. By comparison
with clear coating, PTFE and PTFE- nano aluminum pigmented coatings, the results indicated that
PTFE lowers the protective properties of the waterborne epoxy film although it can provide
lubricating effect. The nano aluminum powder presented the best beneficial effect and resulted in a
significant increase in corrosion resistance of the PTFE- nano aluminum composite coatings. The
corrosion-resistant mechanism of the effect of PTFE and nano aluminum particles in the coating is
discussed.
An Overview of Cold Spray Technique
Authors: Bala Niraj , Singh Harpreet , Prakash S.
Published: March 2009

The Cold spray or cold gas dynamic spraying is the new progressive step in the direction
of development of high kinetic energy coating processes. The cold spray is a method for coating
substrates under atmospheric conditions. In this process micron sized solid particles are accelerated
and transported to substrates by means of supersonic free jets. Upon impacting the substrates,
particles stick to the surface and form coatings which possess very low porosity. The paper outlines
the principles involved in cold spray method and the equipment used for the technique. The cold
spray method is related to classical thermal spray methods but it has some interesting additional
features, which has been discussed in the paper. A fundamental feature of cold spray method i.e.
concept of critical velocity along with the plausible mechanism theory responsible for the
deposition of coating has been discussed briefly. Successful applications of cold spray process and
its environment friendly aspect has been elaborated. It is reported that well founded cold spray
technology will be able to compete for a good market share of VPS/PVD coatings in various fields
like power, electronic/electrical, biotechnology, turbines and other industries. The cold spray
process is still primarily in the research and development stage and only now becoming
commercially available, and has been accepted as a new and novel thermal spray technique mainly
in developed countries. The technology has great potential for future research especially with
reference to its application to real industrial solution.
Effect of Surface on Recrystallization
Authors: Inoko F. , Kashihara Keizo , Okada Tatsuya , Tagami M.
Published: March 2009

It is shown using aluminum single crystals with kink bands like a plate through the depth
that the nucleation and growth of recrystallized grains (RGs) on/in the surface precede those in the
interior.
Surface Characteristics and Corrosion Behavior of Ti-4Al-2V Alloy Implanted with Al and Nb
Authors: Liu Y.Z. , Zu X.T. , Qiu S.Y. , Huang X.Q.
Published: March 2009

A Ti-Al-V alloy was implanted with Al and Nb to flounces ranging from 1 × 1017 to 1 ×
1018 ions cm-2. Glancing Angle XRD measurement revealed α-Ti on Al-implanted samples and
(α+β)-Ti on Nb-implanted samples. The (α+β)-phase samples exhibit better corrosion resistance. In
the aerated solution with pH = 10, all the implanted surfaces are passive. Enhanced reoxidation was
confirmed on implanted surfaces by Auger electron spectroscopy and X-ray photoelectron
spectroscopy analysis. The corrosion in the solution with pH = 10 was governed predominantly by a
TiO2 surface film.
Research on Solution and Aging Treatment of Mg-7Zn-3Al Alloy
Authors: Zhang Jing , Pan Fu Sheng , Zuo Ru Lin
Published: March 2009

Effect of solution and aging treatment on the microstructure of Mg-7Zn-3Al alloy is
studied by using optical microscopy, scanning electron microscopy, X-ray diffraction, transmission
electron microscopy and quantitative image analysis. The results show that the as-aged microstructure
is composed of α-Mg matrix, grain boundary τ (Mg32(Al,Zn)49 ) phase, and fine dispersed τ particles
inside the grain. The solution degree has significant effects on the formation, morphology, and size of
the grain boundary τ phase. The volume fraction and the size of the undissolved eutectic τ phase
decrease with the increase of solution time treated at 325°C. Through sufficient solution treatment,
discontinuous eutectic τ phase retains fine strip morphology after aging, in contrast to the
microstructure in sample undergone insufficient solution which manifests as-cast feature, while at the
same time nano-sized particles precipitate out from the matrix. The precipitates display paralleled
short bar, having certain orientation relationship with the matrix.
Surface Layer Hardness of Austenitic Stainless Steel via Low Temperature Plasma Carburizing and/or Nitriding
Authors: Tsujikawa Masato , Noguchi S. , Yamauchi N. , Ueda N. , Sone T. , Nakata Kazuhiro
Published: March 2009

Surface layer hardness and concentration profiles of austenitic stainless steels after
plasma carburizing and /or nitriding at 673 K were investigated. Carbon and nitrogen concentration
were measured by glow discharge optical emission spectrometry (GDOES) and carbides or nitrides
were detected by x-ray diffraction analysis (XRD) and TEM. The state of carbon at the treated
surface was investigated by Raman spectroscopy. Separation of carburized layer and nitrided layer
was observed in a simultaneous carburizing and nitriding plasma treatment.
Interfacial Microstructure of Titanium Nitride – Titanium Diboride Composite Synthesized by Hot Shock Compaction
Authors: Ii Seiichiro , Nishitani Teruko , Tomoshige Ryuichi
Published: March 2009

Interfacial microstructure of TiN-TiB2 composite, which was synthesized by hot shock
compaction combined explosively shock condolidation and self-propagating high-temperature
synthesis, was investigated by transmission electron microscopy (TEM). In the TiN-TiB2 composite
included 60mol% TiN, an experimentally measured average grain size of the both TiN and TiB2 was
approximately 500nm, and it decreased rather than those of the raw powders. By the conventional
TEM observations, we clarified that there was a specific orientation relationship between cubic TiN
and hexagonal TiB2. The high resolution electron microscopy (HREM) observations revealed that the
TiN/TiB2 interphase boudnaries were atomically flat. We also observed grain boundaries of the
composite and found that no secondary phases such as amorphous phase and precipitates were
observed at the grain boundaries in the composite.
The Recrystallization Behaviour of Nb Microalloyed Steels
Authors: Beladi Hossein , Hodgson Peter
Published: March 2009

The deformation and recrystallization behaviour of a range of Nb microalloyed steels has
been studied using hot torsion. This work focuses on the change from strain dependent to strain
independent recrystallization behaviour as a function of the alloy content, initial microstructure and
deformation conditions. It is found that there is a complex interaction between deformation,
recrystallization and strain induced precipitation, which has significant implications for controlled
rolling in hot strip and plate mills. The data also revealed that the pre-existing precipitates did not
influence the behaviour of post deformation softening.
HRTEM Observation of Precipitates at Early Stage of Aging in Mg-Gd-Zr Alloy
Authors: Kawabata Tokimasa , Matsuno Toshiyuki , Matsuda Kenji , Kamado Shigeharu , Kojima Yo , Ikeno Susumu
Published: March 2009

High resolution transmission electron microscopy（HRTEM）observation was performed
to clarify morphology of precipitates at early stage of aging in Mg-Gd-Zr alloy. In the specimen
aged at 423K, monolayer was observed on {1100}Mg planes. With increasing aging time, the
monolayer and β” phase grew along the <1120>Mg directions. Arrangement of bright dots
corresponding to {020}β’ except for the monolayer and β” phase was observed before peak aging
stage. β’ phases formed at the same aging stage. Thus, these precipitates co-existed before peak
aging stage. The monolayer, β” phase and β’ phase still co-existed in the peak aged specimen.
The β’ phase was dominated in the peak hardness. It is revealed that the monolayer lying on
{1100}Mg act as precursor of β” phase and β’ phase.
Effects of Various Thermal and Environmental Exposure on the Mechanical Properties of Aluminum Alloys
Authors: Lee E.W. , Es-Said O.S.
Published: March 2009

Aluminum alloys 6061-T6, 7075-T6 and 7249-T76 were subjected to several combinations of
solution treatments, quenching media, and age hardening treatments to correlate their mechanical
tensile properties to hardness and conductivity measurements. Additionally, the 6061-T6 and 7075-
T6 alloys were thermally exposed to several temperatures to simulate heat damage effects. The
thermal exposure was correlated to the tensile properties and hardness and conductivity
measurements.
Solute Content and the Tensile Behavior of High Pressure Die Cast Mg-Al Alloys
Authors: Nagasekhar A.V. , Cáceres Carlos H.
Published: March 2009

Binary Mg-Al alloys with varying content of aluminium from 0.5 to 12mass% have been
studied. The proof stress increase in two steps whereas the ductility exhibits two correlated stepwise
drops, as the aluminium content increases. The first increase in strength, and attendant drop in
ductility, is observed between 4 and 5 mass% Al. The second stepwise change is observed between
10 and 12 mass% Al. These effects are connected with well defined changes in the microstructure:
at 4 mass% a dispersion of β-phase intermetallic particles appears in the core region and a closed
cell structure develops near the surface; at 12 mass% Al, the increased volume fraction of the β-
phase intermetallics extends the interconnected network of intermetallics to include the core region
as well. The micromechanics of the strengthening and decreased ductility are discussed.
Electromagnetic Stirring Processing and its Influence on Mechanical Properties of ZL102(or Al-Si) Alloy
Authors: Zhang Xue Feng , Du Yong Sheng , Qi Li Ying , Liu Guan Yuan
Published: March 2009

Al-Si alloy was melted by using vacuum induction melting furnace heated with
medium-frequency induction and stirred simultaneously under Lorentz force. The experimental
results were discussed with respect to the theoretical analysis of the Lorentz force on the molten alloy.
It was found that Si phase tends to homogenize and aggregate along the direction of axis in the alloy
under the effect of Lorentz force. With increasing stirring duration, Rod-shaped Si phase has a
tendency to break and passivate on the edge. Vickers hardness measurement indicated that the
microhardness of Al-Si alloy was improved after electromagnetic stirring. This result can be mainly
attributed to the improvement in spheroidization of Si phase and aluminum phase.
Resistance of Thin Al Foam Panels to Deep Indentation
Authors: Idris Maizlinda I. , Vodenitcharova Tania , Hoffman Mark
Published: March 2009

In recent years there has been a considerable amount of research into the deformation
behaviour of metallic foams. The majority of this research has only addressed size-independent bulk
material properties, obtained through uniaxial compression and indentation tests of thick blocks.
There is little information in the literature on the indentation response of thin panels, which has
motivated the current study. Thin panels of ALPORAS closed-cell foam of ~ 0.25 g/cm3 density
were tested in uniaxial compression, and were indented with long flat-plate punches and long
cylindrical punches. Cross-sectioning of the samples following interrupted testing revealed the
plastic strain evolution process. The deformation was attributed to the progressive crushing of the
cell bands, and the combined action of shearing and tearing resistance. Based on energy formalism,
a model was developed to estimate the crushing force. By fitting the experimental loaddisplacement
curves, the foam ligament tearing energy was deduced for all types of indentation. The
absorbed energy was also calculated for the uniaxial compression and indentation experiments.
Preparation of Ti-Al Intermetallics by Aluminum Melt Infiltration-Diffusion Annealing Technique
Authors: Chen Li Qing , Wang Ji Jie , Chen Lin
Published: March 2009

A novel process, of melt infiltration combined with diffusion annealing technique, was
developed to prepare Ti-Al intermetallics at temperature lower than ingot melting point. In this
process, a porous Ti preform was firstly fabricated and the Al melt was reheated to temperature
slightly higher than Al melting point to infiltrate the porous Ti preform by capillary force
spontaneously. After long-time high-temperature diffusion annealing, Ti-Al intermetallic compound
can be finally synthesized from the bulk Tip+melt Al via diffusion. As example, Ti-46Al
intermetallics has been fabricated, and the microstructures and the phases of the as-synthesized
intermetallics were characterized by XRD and SEM. The compressive behavior of the as-synthesized
Ti-Al at elevated temperatures has been studied and the reaction mechanism involved in the process
finally analyzed.
Strengthening and Ductilization of D03-Type Fe3Al Intermetallic Alloys by Dispersion of Laves Phases Fe2Zr and Fe2Nb
Authors: Matsumoto N. , Kaneno Yasuyuki , Takasugi Takayuki
Published: March 2009

Zr and/or Nb added Fe3Al based intermetallic alloys (i.e., Fe3Al-Zr, Fe3Al-Nb and
Fe3Al-Zr-Nb) were arc-melted, homogenized, hot-rolled and then annealed to evaluate microstructure
and tensile property at room temperature as well as at a high temperature (873K). After annealing,
the rolled alloys exhibited a recrystallized microstructure containing coarse second phase particles,
except for the Nb-added alloy with a minor content of Nb. Relatively high tensile elongation as
well as high tensile strength was observed at room temperature in the Zr-added alloys with a minor
amount of Zr. Also, these alloys showed relatively high tensile strength and elongation at high temperature
(873K). The results suggest that tensile ductility as well as strength of Fe3Al-based alloys
can be improved by introduction of the second phase dispersions.
Phase Equilibria between γ-Fe (A1) and Fe2Ti Laves (C14) Phases and Microstructure in Fe-Ti-Ni Ternary System at Elevated Temperatures
Authors: Sugiura Tomoaki , Ishikawa Shigehiro , Matsuo Takashi , Takeyama Masao
Published: March 2009

The phase equilibria among α-Fe, γ-Fe and Fe2Ti phases in Fe-Ti-Ni ternary system at
1473 K and 1373 K with Ni (γ former element) addition were examined, by paying attention to the
γ+Fe2Ti two-phase region. The Fe2Ti single-phase region extends toward the equal-titanium
concentration direction up to about 30 at% Ni, and the Laves phase becomes in equilibrium with
γ-Fe by 12 at% Ni addition, but the γ+Fe2Ti two-phase region is limited because of the formation of
liquid phase by further Ni addition at 1473 K. With decreasing temperature, a ternary eutectic
reaction (L→γ-Fe+Fe2Ti+Ni3Ti) occurs, making the two-phase region wider just below the
invariant reaction at 1373 K, and the region becomes narrower again by the enlargement of the
three-phases region toward Fe-rich side.
Study of the Preparation Technology and Properties of BaBi4Ti4O15 Ceramics
Authors: Huang Jin Liang , Li Li Hua , Zhang Ke , Yin Biao
Published: March 2009

BaBi4Ti4O15 ceramics was prepared by molten salt synthesis method (MSS) and
conventional solid phase process (CS). The phase of reaction products and the microstructure were
detected by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results show that
the evident anisotropic flake structure of BaBi4Ti4O15 powder prepared by MSS was obtained at
850°C and the level of anisotropy of BaBi4Ti4O15 powder decreased with increasing temperature.
After calcined at 950°C, sintering in the range of 1100~1170°C, the sintering temperature and the
maximum permittivity of BaBi4Ti4O15 ceramics prepared by MSS at same frequency was lower than
those prepared by CS. Additionally, the apparent degree of orientation was obtained and the lotgering
factor (f) calculated according to the XRD results showed a value of 0.63.
Edge Effects in Sliding Wear Behavior of ZrO2-WC Composites and WC-Co Cemented Carbides
Authors: Bonny Koenraad , de Baets Patrick , Van der Biest Omer , Vleugels Jef , Lauwers Bert
Published: March 2009

A trend in the development of WC based cemented carbides and zirconia based ceramic
composites is grain size refinement and more narrow grain size distributions of the starting powder,
in order to accomplish higher hardness and abrasive wear resistance. The current work reports the
results of dry sliding wear experiments on laboratory-made electrically conductive ZrO2-WC
composites and commercially available WC-Co based cemented carbides, which have been
manufactured and finished by rough cutting wire EDM with consecutive execution of gradually
finer EDM regimes. Tribological data are obtained using a small-scale pin-on-plate test rig. Wear
tracks are analyzed by surface scanning topography and scanning electron microscopy, revealing
that the outer extensions of the wear tracks exhibit some differences in wear behavior compared to
the central parts.
Fabrication of Alumina and Silicon Carbide Fibers from Carbon Fibers
Authors: Lin Yung Jen , Shen Shin Yi
Published: March 2009

Carbon fibers of ~9 μ m in diameter were used as templates to fabricate alumina and
silicon carbide fibers. The carbon fibers were placed in a vacuum furnace with aluminum and heated
at 1100°C for 8 h to form aluminum carbide. Then, the aluminum carbide fibers were oxidized in air
at 1500°C. The resulted fibers were hollow and the alumina layer was porous in the interior. To
fabricate silicon carbide fiber, carbon fibers were reacted with Si at 1300°C -1500°C in Ar. The
thickness of silicon carbide layers increased with reaction temperature and reaction time. Solid fibers
could be obtained after reaction at 1400°C for 4 h. In contrast to porous alumina layer, the silicon
carbide layer/fibers were dense. The porous alumina hollow fibers were fragile while the solid silicon
carbide fibers were flexible. BET surface area measurements revealed that the porous alumina had
surface area as high as ~100 m2/g.
Surface Nano-Deformation Behavior in Particle-Reinforced Al Composite
Authors: Tanaka Yoshihisa , Liu Yu Fu , Kagawa Yutaka
Published: March 2009

The surface nano-deformation behavior in metal matrix composite during tensile loading
was investigated by in-situ atomic force microscope (AFM) observation. The composite material
used was aluminum matrix reinforced with 10 and 20 percent volume fraction of SiC particles. The
average size of the reinforcement was 3 μm. Tensile test and in-situ observations were conducted
using a loading device equipped with an AFM. Surface morphologies of the composite specimens
were acquired before the loading and at various stages of the loading. The microstructural damage
and the evolution of surface roughness were studied. The effect of volume fraction of the reinforcement
on the nano-deformation behavior and damage evolution process of the composite based
on nanoscale in-situ AFM observation will be discussed.
Effect of Boron on the WC Morphology in Sub Micron Tungsten Carbide-Aluminide Composites
Authors: Ahmadian M. , Chandra Tara , Wexler David , Calka Andrzej
Published: March 2009

The effect of boron on the WC morphology and on the grain size of binders in sub micron WC
composites containing Fe60Al40 and Ni3Al binders was investigated using scanning electron
microscopy (SEM) and transmission electron microscopy (TEM). The composites were prepared
under uniaxial hot pressing of milled powder samples at 1500 °C in inert argon atmosphere. Doped
aluminides with boron levels ranging from 0 to 0.1 wt% were used as the binders. It was found that
the microstructural characteristics of boron doped aluminide WC composites were similar to those
of hot pressed WC-Co and commercial grade WC-10wt%Co (H10F) hardmetals. The contiguity of
WC particles (WC/WC contact) and the grain sizes of aluminides decreased and the extent of
faceting of tungsten carbide increased in the aluminide tungsten carbide composites in
presence of boron.
Synthesis of 1, 2-Aceanthrylenedione Catalyzed by Anhydrous AlCl3
Authors: Zhang Chun Yan , Chen Min , Zhang Yan , Yuan Xin Hua , Liu Hua
Published: March 2009

1,2-aceanthrylenedione was synthesized through the acylation reaction of anthracene and
oxalyl chloride catalyzed by anhydrous AlCl3. The effects of various reaction conditions on the yield
and selectivity of 1, 2-aceanthrylenedione were studied by GC analysis. The results show that the
optimum synthesis conditions of the acylation reaction are as follows : the molar ratio of oxalyl
chloride to anthracene being 1:2, the molar ratio of anhydrous AlCl3 to anthracene being 4:1, the
reaction time being 5 h, the reaction temperature being 303k and the solvent of the reaction system
being CS2. Under those conditions, the yield and selectivity of 1, 2-aceanthrylenedione is 83.8 % and
92.3% respectively. Pure 1, 2-aceanthrylenedione was prepared by extraction and recrystallation. The
structure of 1, 2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and
1HNMR analyses.
Synthesis and Mechanical Properties of Advanced Polyimide/Silicon Dioxide Nanocomposites
Authors: Zhang Qing Xin , Naito Kimiyoshi , Kagawa Yutaka
Published: March 2009

Hybrid inorganic-organic materials based on a polyimide (PI) and silicon dioxide (SiO2)
were prepared previously only via sol-gel approach. However, sol-gel processes have some critical
limitations. The primary drawback is that the resultant gel is extremely fragile and sol-gel process is
complicated and costly. In this study, using SiO2 nanoparticles polyimide/SiO2 nanocomposites
were synthesized from 4,4'-diaminodiphenyl ether (ODA) and 3,3',4,4'-benzophenonetetracarboxylic
dianhydride (BTDA). A coupling agent, 3-glycidyloxyporpl trimethoxysilane
(GTMOS), was used to functionalize the SiO2 nanoparticles which enhanced the compatibility
between polyimide and SiO2 nanoparticles. The microstructures of polyimide/SiO2 nanocomposites
were characterized by Fourier transform infrared spectroscopy (FT-IR) and wide angle X-ray
diffraction (WAXD). All the polyimides show typical noncrystalline X-ray diffraction. The frequent
occurrence of particular interatomic distances (R) denoted by the noncrystalline WAXD maxima
were determined. All the modulus, strength and fracture strain of polyimide were improved with 5
wt% SiO2 modified with the coupling agent.
Electrical Conductivity of VGCF/ Aluminum Composites Fabricated by Electro Spark Sintering
Authors: Sasaki Gen , Kondo Fumiaki , Matsugi Kazuhiro , Yanagisawa Osamu
Published: March 2009

Vapor grown carbon fiber (VGCF) was sleaved in acetone with ultrasonic vibration. Then
pure aluminum powders with 3 μm in average diameter was poured into VGCF containing acetone
and mixed with ultrasonic vibration. The composites were fabricated by electro spark sintering. The
strength, rigidity, electrical conductivity and microstructure of the composites was investigated.
VGCF was distributed uniformly and no pores was observed in composite. As increasing the
volume fraction of VGCF in composites, the strength of composites increased gradually but the
elongation decreased. The electrical resistivity of the composites increased as increasing VGCF
content, constantly. The theoretical resistivity of composites without residual stress is lower than
that of experimental results. It seems that is caused by the high dislocation density and strain
introduced by big difference of thermal expansion between VGCF and pure aluminum.
Mechanical Properties of Nano-Laminar Glass/Metal Composite
Authors: Kakisawa Hideki , Sumitomo Taro , Owaki Yusuke , Kagawa Yutaka
Published: March 2009

A nano-laminar glass/metal composite was fabricated. Glass flake powder coated with
silver was used as the raw material, and was sintered by hotpressing. Samples fabricated in the
optimum condition had a dense, laminar microstructure originating from the aligned flake powder.
The result of a three-point bending test for the samples suggested that the alignment of the powder
was essential for fracture behavior: When the powder was aligned in advance during the green sample
fabrication, the sample fractured stably after the maximum load, while the samples fabricated by
simple hotpressing of the powder without pre-alignment fractured unstably. Work of fracture of the
sample in which the powder was well aligned was measured with chevron notched specimens; a
significantly high value of about 300J/mm2 was obtained.
Study on Toughening Mechanism of Nano-Composite Ceramics Prepared by Mixed Coagulative Method
Authors: Zhao Bo , Gao Guo Fu , Wu Yan
Published: March 2009

In this work the toughening mechanism and the microstructure of SPS-sintered Al2O3-ZrO2
nano-composite ceramics whose powder was prepared by mixed coagulative method, was studied.
The study showed that the grain shape of Al2O3 was changed due to the additive ZrO2 and its density
was improved in the Al2O3- ZrO2 ceramics. Meanwhile its grain was refined. The microstructure was
the typical nano-composite ceramics mixed with intracrystalline and intercrystalline structure. The
irregular aggregation of ZrO2 mostly existed on the grain boundary, where many grains of Al2O3
intersected. Some thin and dispersal globular nano grains (70nm-200nm) of ZrO2 were distributed in
the Al2O3 crystal grains. That enhanced the mechanical performance of the matrix because of the
refined grain and the intracrystalline nanometer structure. The study also showed that the changes of
the mechanical performance of Al2O3-ZrO2(n) ceramic resulted from toughening mechanism
introduced by nanometer grains, toughening mechanism introduced by ZrO2 phase transition and the
intracrystalline structure.
Fabrication of Structural Composite Accompanied with a Function of Thermoelectric Conversion
Authors: Takayama Yoshimasa , Abe T. , Yashiro T. , Watanabe Hideo , Kato Hajime
Published: March 2009

The composite accompanied with a function of thermoelectric conversion has been
fabricated. It was a fiber metal laminate (FML) consisting of two aluminum alloy sheets of 0.5mm
thickness and a central layer of glass fiber reinforced plastic (GFRP). The central layer with a
thickness of 1mm included thermoelectric elements of Bi-Te based alloys between glass fibers. The
mechanical properties of FML with and without the thermoelectric elements were evaluated by tensile
and bending test. The thermomechanical properties were measured by a potentiometer for a module
with heated and cooled sides, and plotted a potential as a function of difference in temperature
between both sides.
Microstructure and Mechanical Properties of the Spray-Deposited Al-10.8Zn-2.8Mg-1.9Cu Alloy at Various Aging Conditions
Authors: Wang Feng , Xiong Bai Qing , Zhang Yong An , Zhu Bao Hong , Liu Hong Wei , Mi Xu Jun , He Xiao Qing
Published: March 2009

In this paper, Al-10.8Zn-2.8Mg-1.9Cu alloy was synthesized by the spray atomization and
deposition technique. The microstructure and mechanical properties of the spray deposited alloy at
various aging conditions (T6, T73 and RRA treatment) were studied using high-resolution electron
microscopy, selected area diffraction, and tensile tests. The results indicate that the two types of GP
zones, GPI and GPII zones are major precipitates for the alloy under peak-aged condition. The peak
UTS and YS values achieved at an ageing temperature of 120 °C was 818 MPa and 793 MPa. Under
two-step aging condition, the GP zones and η’ are major precipitates for the alloy, the discontinuous
grain boundary precipitates are favorable to SCC resistance in over-aged condition, which reduces its
strength 58 MPa(about 7%) comparing to the peak-aged condition. RRA treatment decreased ultimate
tensile strength 25 MPa (about 3%) in values compared with the alloy at T6 condition.
Microstructures and Phase Transformations of Ti-50.9at%Ni Alloy Processed by Equal Channel Angular Extrusion at Medium Temperature
Authors: Xie Chao Ying , Fan Zhi Guo
Published: March 2009

Submicron-grained Ti-50.9at%Ni alloy was prepared by Equal Channel Angular Extrusion
(ECAE) at medium temperature(500°C). Microstructure evolution and phase transformations of
Ti-50.9at%Ni alloy after ECAE processes at medium temperature have been investigated by optical
microscope, TEM and DSC tests. It is found that the initial coarse grains of Ti-50.9at%Ni alloy were
refined into submicron grains, smaller than 0.5 um in size, after eight passes ECAE at 500°C.
Martensitic transformation temperatures decreased remarkably after one pass ECAE and more gently
with increasing the pass number of ECAE. R phase transformation was stimulated after ECAE
processes and underwent within a larger temperature range with an ambiguous thermal peak. The
reverse R phase and reverse martensitic transformations, during heating, were separated eventually
after eight passes ECAE.
Mapping of the Granular Flow during the Irreversible Deformation Processes in Spatially Extended Polycrystalline Systems
Authors: Muñoz-Andrade Juan Daniel
Published: March 2009

The objective of this work is to obtain the mapping of the granular flow during the
irreversible deformation processes in spatially extended polycrystalline systems (SEPCS) in order
to describe and analyse the phenomenology and mechanics of the granular flow. In general, it was
established for commercial alloys that, the granular flow is linked with the hyperbolic motion due
to dislocation dynamics and self accommodation of grains. Also, the recession velocity of grains in
the stain field on the surface of SEPCS increased with the distance along the tension axis from the
origin of the coordinate system of reference. This behaviour is very similar to the Hubble flow
associated with the expansion process of the universe, where the recession velocity of the galaxies
increased in a linear relationship with their distance. In this physical framework the main results are
analysed in the context of the unified interpretation of the Hubble flow, plastic flow and super
plastic flow [1-6].
Fine-Grained Structure in Extruded Magnesium Alloy with Long-Period Stacking Order Phase
Authors: Morikawa Tatsuya , Kinoshita Daisuke , Kawamura Yoshihito , Higashida Kenji
Published: March 2009

Microstructures developed by warm extrusion for Mg97Zn1Y2 alloy including long-period
stacking order (LPSO) phase have been investigated using SEM and TEM. The extruded magnesium
alloy with LPSO phase exhibits high strength and sufficient ductility. Such superior mechanical
properties appear by warm extrusion around the temperature of 623K. The microstructure of the
extruded alloy consists of matrix of fine-grained hcp phase and elongated grains with fine-lamellae
including LPSO phase. The grain size of hcp matrix was about 1μm, indicating that remarkable
grain refinement was occurred by extrusion since the grain size of as-cast alloy was about 500μm.
Special attention has been paid on the enrichment of solutes at stacking faults and grain boundaries
in the fine-grained matrix, which would contribute not only to the strengthening but also to the stability
of fine-grained structure because of its role of an inhibiter against grain coarsening.
An Investigation on the Microstructure and Mechanical Properties of Mg-3Al-1Zn Alloy via Spray Forming
Authors: Li Yong Bing , Cui Hua , Huang Jin Feng , Cai Yuan Hua , Wang Zi Han , Zhang Ji Shan
Published: March 2009

In this study, cylindrical billets of Mg-3Al-1Zn (AZ31) alloy have been synthesized by
spray forming technique. The alloy billets were hot-extruded into rods with proper processing
parameters. The microstructures and mechanical properties of alloys were investigated. The results
indicated that spray formed AZ31 alloys have a homogeneous and equiaxial grains with average grain
size of 20μm. The further grain refinement with an average grain size of 5μm was attributed to the
continuous dynamic recrystallization during the extrusion processing. The room temperature
mechanical properties of the extruded rods are remarkably higher than those of as-cast AZ31 alloy.
The average tensile ultimate and yield strength of the alloy are 321MPa and 237MPa, respectively,
with an elongation of 15.2%.
Relationship between Saturation Curve and Peening Parameters for Aerospace Shot Peening Process
Authors: Huang Chi Kong , Torng Chau Chen , Chang Hsien Ming
Published: March 2009

The shot peening process can improve the fatigue strength of machine parts of aero
structures. Due to the strength requirement of aircraft, the shot peening is widely used in the
manufacturing process. Most of shot peening parts peened after penetrate inspection to ensure no
defect and crack on the surface, and then peen the shots on the surface of machine parts to increase the
fatigue life. During the first article verification period, the saturation curve has to be created. The
peening parameters of mass production would base on the peening parameters of saturation point of
the saturation curve. By using statistical methodology to analysis saturation curve of shot peening
process, this study tries to find the relationship between saturation curve and relative peening
parameters, such as peening time, air pressure. The results of this analysis can provide an efficient and
economical approach for the process engineer and technician to develop the new shot peening
process.
Experimental Study of Grain Growth in Aluminium Melts under the Influence of Ultrasonic Melt Treatment
Authors: Atamanenko T.V. , Eskin Dmitry G. , Katgerman Laurens
Published: March 2009

It was shown on laboratory and industrial scale that ultrasonic melt treatment (UST)
significantly refines structure of aluminium alloys and improves the quality of castings. However,
despite considerable efforts which have been made over decades in the field of ultrasonic processing
of aluminium melts, quite a few problems remain unclear. One of them is addressed in this project.
The aim of the project is to understand which mechanism is responsible for cavitation-aided grain
refinement. It is expected that the knowledge gained as a result of this work can be used in directchill,
shape and die casting. The paper describes an experimental setup and first results on the
correlation between parameters of UST, solidification conditions and degree of structure refinement.
In separate experiments, a model Al-Cu alloy with different amount of solidification sites is
solidified with and without UST. The final microstructure is analyzed.
Microstructural Characterization of Oxide Scale Formed by Early Stage of Oxidation of 17%Cr-Mn-Ni Austenitic Stainless Steel
Authors: Oshima Takayuki , Yamaguchi Yutaka , Kuroda Kotaro
Published: March 2009

The microstructure of oxide scale formed in the early stage of oxidation of cold-rolled sheets of
17%Cr-Mn-Ni austenitic stainless steel was examined using SEM and TEM. Samples were oxidized at 973
to1373K for 1 to 15min. Nodules were observed on the surfaces of specimens oxidized at 1173K. The nodules
were composed of two layers, which comprised Fe oxides and Cr-rich Fe-Cr-Mn oxides, respectively. The
other scale was composed of two layers of Fe-Cr-Mn oxides with different compositions. Nodules were not
observed on the surfaces of the specimens oxidized at 973 and 1373K. After oxidation at 1373K for 1min, the
scale was composed of three layers. The first layer consisted of Fe-Mn oxides with a spinel structure, the
second consisted mainly of Cr oxides, and the third consisted of Cr-Mn oxides containing a small amount of
Fe.
Detonation Velocity and Pressure of Ammonium Nitrate and Activated Carbon Mixtures
Authors: Miyake Atsumi , Echigoya Hiroshi , Kobayashi Hidefumi , Katoh Katsumi , Kubota Shiro , Wada Yuji , Ogata Yuji , Ogawa Terushige
Published: March 2009

To obtain a better understanding of detonation properties of ammonium nitrate (AN) and
activated carbon (AC) mixtures, steel tube test was carried out for stoichiometric composition of
powdered AN and AC mixtures and the detonation velocity and the pressure profile were measured.
Based on the results obtained the relation between the detonation velocity and the peak pressure was
discussed with the theoretically predicted values which were obtained by the thermohydrodynamic
CHEETAH code with the BKWC equation of state. The measured detonation velocity and peak
pressure were far below the theoretically predicted values and the non-ideal detonation behaviour was
confirmed.
Novelties in Physics of Explosive Welding and Powder Compaction
Authors: Plaksin I. , Campos J. , Ribeiro J. , Mendes R. , Direito J. , Braga D. , Prümmer Rolf
Published: March 2009

Widely known technologies of explosive (X) welding and explosive (X) powder
compaction are based on applications of porous composite solid or liquid explosives. Recent results
on dynamics of X-welding and X-powder compaction are presented and discussed in this paper in
the conceptual context of an orderly oscillating detonation wave (DW), a synergetic phenomena
observed in detonation of all classes of composite energetic materials, that was discovered in
LEDAP in last eight years. Regular instabilities that are induced by oscillating DW, are transmitted
through the interface of the impacted materials, causing the local instability and fluctuations in both
processes, formation of the interfacial waves (X-welding mechanism) and in an initial phase of
powder compaction. Application of high resolution optical probes (spatial resolution 250 *m,
temporal resolution 1 ns, 96 independent channels) allowed the simultaneous registration of the
oscillating DW in the X-charge and transmission of oscillations, trough the flyer plate, up to the
welding zone. Similar measurements have been made in experiments with X-compaction of
tungsten powder providing the continuous registration of shock wave velocity inside the compacted
powder, its geometrical shape, their instabilities and irregularities.
Study of Phase Transformations in Heat Treatment of HVOF Thermally Sprayed WC–17Co Coating
Authors: Khameneh Asl Shahin , Sohi M. Heydarzadeh , Hokamoto Kazuyuki , Matsuda Mitsuhiro , Tomoshige Ryuichi , Nishida Minoru
Published: March 2009

In this work, WC-17Co powder was thermally sprayed onto mild steel using HVOF spray technique. The coated specimen was heat treated at 1100°C in a vacuum chamber and was then studied by using transmission electron microscopy (TEM). Post heat treatment resulted in recrystallization of the amorphous phase, formed during thermal spraying, into low carbon eta phase like Co6W6C. TEM results of the heat treated specimens showed that these new nucleated eta phases had very clear crystallographic structure without any crystalline defects. Heat treatment could also transform high carbon carbides like WC and W2C in the as sprayed samples to high carbon eta phases like Co3W3C. High density of dislocations and staking faults noticed in TEM of these phases might be an indication of possible shear mechanism in formation of these carbides.
New Impact Testing Methods for Sheet Metals Based on SHPB Technique
Authors: Hasebe Tadashi , Imaida Yutaka
Published: March 2009

This paper proposes new impact testing methods applicable to sheet metals both under
tension and compression based on widely used split Hopkinson pressure bar (SHPB) technique.
Explicit dynamic finite element simulations by using LS-DYNA 3D are systematically conducted
for several specimen clamping conditions to seek the appropriate methodologies to realize the two
tests. For the tensile test, a method which can reduce stress oscillations that usually appear in the
measured stress-strain curves is proposed and is devised to be used with SHPB technique. For the
compression test, a candidate which can restrict buckling of the specimen is proposed. The method
uses a special die-set sandwiching the sheet metal specimen which is simultaneously compressed
without disturbing the planar stress wave to be propagated.
Nondestructive Evaluation of Rayleigh Pitch-Catch Contact Ultrasound Waves on Impacted-Damaged Composites
Authors: Park Je Woong , Yang In Young , Im Kwang Hee , Hsu David K. , Song Sung Jin , Kim Hak Joon , Cho Young Tae
Published: March 2009

In particular, CFRP (carbon fiber reinforced plastics) composite materials have found
wide applicability because of their inherent design flexibility and improved material properties.
CFRP composites were manufactured from uni-direction prepreg sheet in this paper. However,
impacted composite structures have 50-75% less strength than undamaged structures. It is desirable
to perform nondestructive evaluation to assess material properties and part defect in order to ensure
product quality and structural integrity of CFRP. In this work, a CFRP composite material was
nondestructively characterized and a pitch-catch technique was developed to measure impacteddamaged
area using an automated-data acquisition system. Also one-sided mode was performed to
scan defect both manual contact measurement and an immersion tank. It is found a pitch-catch
signal was found to be more sensitive than normal incidence backwall echo of longitudinal wave to
subtle flaw conditions in the composite, including fiber orientation, low level porosity, ply waviness,
and cracks. The paper describes the depth of the sampling volume with the head-to-head miniature
Rayleigh probes and also ultrasonic C-scan images are acquired experimentally using one-sided
measurement and a conventional scanner.
Multi-Physics Modeling Based on Combustion of Energetic Materials
Authors: Kim Ki Hong , Yoh Jai Ick
Published: March 2009

We present an innovative method of multi-physics application involving energetic
materials. Energetic materials are related to reacting flows in extreme environments such as fires
and explosions. They typically involve high pressure, high temperature, strong non-linear shock
waves, and high strain rate deformation of metals. We use an Eulerian methodology to address
these problems. Our approach is naturally free from large deformation of materials that makes it
suitable for high strain-rate multi-material interaction problems. Furthermore we eliminate the
possible interface smearing by using the level sets. We have devised a new level set based tracking
framework that can elegantly handle large gradients typically found in reacting gases and metals.
We show several work-in-progress applications of our algorithm including the Taylor impact test,
explosive venting and additional confined explosion problems of modern interest.
The Character of the Solidification Structure of Massive Ductile Cast-Iron Castings and its Prediction
Authors: Stránský Karel , Dobrovská Jana , Kavička František , Stetina Josef , Sekanina Bohumil , Franek Zdenek
Published: March 2009

An original three-dimensional (3D) model of solidification is used to describe the process
of solidification and cooling of massive 500x1000x500 mm cast-iron castings in sand moulds. The
calculated model of the kinetics of the temperature field of the casting is verified during casting
with temperature measurements in selected points. The following dependences are later determined
according to the experimental and calculated data: the average size of the graphite spheroids rg,
graphite cells Rb and the average distances among the particles of graphite Lg – always as a function
of the local solidification time θ [xi, yi, zi]. Furthermore, it has been found that the given basic
characteristics of the structure of the cast-iron (rg, Rb and Lg) are a linear function of the logarithm
of the local solidification time θ. The original spatial model of solidification can therefore be used
in its first approximation for the assessment of the pouring structure of massive cast-iron castings.
Influence of Crystalline Elasticity on the Stress Distribution at the Free Surface of an Austenitic Stainless Steel Polycrystal. Comparison with Experiments
Authors: Sauzay Maxime , Man Jiří
Published: March 2009

This numerical study focuses on the recent observations of Man et al. [4] showing welloriented
grains presenting no Persistent Slip Marking even if PSMs are observed in 86% of the
surface grains in 316L austenitic stainless steel cycled at room temperature up to 60% of fatigue
life. Scanning Electron Microscopy (SEM) permits us to build Finite Element (FE) meshes of the
observed aggregates and to assign to the modelled grains the crystallographic orientations measured
by Electron Back Scattering Diffraction (EBSD). Then, 3D FE computations using crystalline
elasticity allow the evaluation of mean grain stress tensors and resolved shear stresses. The results
could explain qualitatively the anomalous behaviour of the studied well-oriented grains which is
partly due to the particular orientations and shapes of the neighbour grains. This study highlights the
influence of crystalline elasticity and neighbour grains in microplasticity and crack nucleation.
Heterogeneous Pattern Formation at Aluminum Surface — Fourier, Morphology and Fractal Analysis
Authors: Gordienko Yuri , Zasimchuk Elena , Gontareva Rimma
Published: March 2009

Surface analysis of the aluminum thin plates plastically deformed under constrained
cyclic deformation was performed by Fourier, morphology and fractal techniques. The plates are
used for estimation of deformation damage and fracture in places with a priori known homogeneous
and heterogeneous strain distribution. Advantages and disadvantages of Fourier, morphology and
fractal techniques for characterization of the intersections and projections are discussed in the
context of its applicability to investigation of plastic deformation and fracture (persistent strain
planes and directions, strain localization angles and places, etc.).
Contributions to Internal Stress from Free Dislocations and from Substructure Boundaries in Dislocation Structure Formed in High Temperature Creep
Authors: Orlová Alena , Dobeš Ferdinand
Published: March 2009

The relation of the internal stress and the parameters of the heterogeneous dislocation
structure was suggested in the form of the classical Taylor formula relating the internal stress to the
total dislocation density stored in the subgrain interior and in the subgrain boundaries. The other
formula combines linearly the stress contribution generated by network dislocations and the stress
contribution of the subgrain structure semiempirically related to the subgrain size. The formulas can
evaluate the ratio of internal stress components due to sub-boundaries and free dislocations.
Hard Nano-Crystalline Coatings for Cutting Tools
Authors: Piska Miroslav
Published: March 2009

Modern trends in metal cutting, high speed/feed machining, dry cutting and hard cutting set
more demanding characteristics for cutting tool materials. The exposed parts of the cutting edges
must be protected against the severe loading conditions and wear. The most significant coatings
methods for cutting tools are PVD and CVD/MTCVD today. The choice of the right substrate or
the right protective coating in the specific machining operation can have serious impact on
machining productivity and economy. In many cases the deposition of the cutting tool with a hard
coating increases considerably its cutting performance and tool life. The coating protects the tool
against abrasion, adhesion, diffusion, formation of comb cracks and other wear phenomena.