bluuebunny/crossref_metadata_2025 huggingface dataset:
The Electrical Properties of PLZT Thin Films on ITO Coated Glass with Various Post-Annealing Temperature
Authors: Cha Won Hyo , Yoon Ji Eon , Hwang Dong Hyun , Lee Chul Su , Lee In Seok , Son Young Gook
Published: March 2009

Lanthanum modified lead zirconate titanate (Pb1.1La0.08Zr0.65Ti0.35O3) thin films were
fabricated on indium-doped tin oxide (ITO)-coated glass substrate by r.f magnetron sputtering
method. The thin films were deposited at 500°C and annealed at various temperature (550~600°C) by
rapid thermal processing. The structure and morphology of the films were characterized with X-ray
diffraction and atomic force microscopy. The hysteresis loops and fatigue properties of thin films
were measured by precision material analyzer. As the annealing temperature increased, the remnant
polarization value increased from 10.58 DC/cm2 to 31.35 DC/cm2, coercive field was reduced from
79.906 kV/cm to 60.937 kV/cm. For the switching polarization endurance analysis, the remnant
polarization of PLZT thin films annealed at 700°C was decreased 15% after 109 switching cycles
using 1MHz square wave form at 5V.
Nanocrystalline TiO2 Coated-Fabric for UV Shielding and Anti-Bacterial Functions
Authors: Nimittrakoolchai O. , Supothina Sitthisuntorn
Published: March 2009

Due to excellent photocatalytic and optical properties of titanium dioxide (TiO2), it has
been applied in several products such as food packaging plastics, materials for vehicles or for
buildings and sunscreen-protecting cosmetics. In this present work, the synthesized as well as
commercial TiO2 was coated onto a household curtain fabric for anti-microbial and ultraviolet (UV)
shielding functions. The coating was performed by inducing the deposition of TiO2 layer from the
Ti precursor onto the fabric surface pre-treated with silane adhesive agent so as to improve the
adhesion. Ag nanoparticles were also incorporated in some samples to further improve the antibacterial
function. Anti-bacterial activities of the coated fabric were evaluated by standard
qualitative test (the Kirby-Bauer test (AATCC 147)). Efficiency for UV shielding was evaluated by
measuring a UV-Vis reflection of the coated fabrics both before and after subjecting to several
washing cycles. The result showed that the TiO2-coated fabrics developed had potential as antibacterial
and UV shielding for the curtain industry.
Synthesis of Metal Hydrides by Cold Rolling
Authors: Pedneault Sylvain , Roué L. , Huot Jacques
Published: March 2009

In the development of metal hydrides for commercial applications, a special attention
should be devoted to the ways of production. For commercial success, the raw elements of the
hydrogen storage materials should be of low cost, the synthesis process should be inexpensive and
easily scalable. Therefore, it is important to put some effort on the elaboration of new and more
efficient means of producing metal hydrides. In this perspective, cold rolling was investigated as a
new means of producing nanocrystalline materials. This technique is well-known in the industry and
easily scalable. Cold rolling was performed on Mg-Ni system. The evolution of morphology, crystal
structure, crystallite size, deformation, and preferred orientation was studied as a function of
number of rolling passes. Cold rolling followed by a heat treatment produced the intermetallic
Mg2Ni. Without heat treatment and for a large number of rolling, an amorphous phase was
synthesized.
Synthesis of MgH2 and Mg2FeH6 by Reactive Milling of Mg-Based Mixtures Containing Fluorine and Iron
Authors: Vaichere Antoine , Leiva Daniel Rodrigo , Ishikawa Tomaz Toshimi , Botta Filho Walter José
Published: March 2009

A good method to store hydrogen is in it atomic form in crystalline structure of metals at
low pressure. Thanks to magnesium’s high hydrogen storage capacity, its low weight and its high
natural abundance, it is an attractive material to develop hydrogen solid state storage. The
production of Mg-based nanocomposites can enhance the kinetics of H-sorption of magnesium and
the temperature of release of hydrogen. Transition metals as iron, which have important catalytic
activity in hydrogen reactions with Mg, and the surface protective compound MgF2, are interesting
additions for magnesium mixtures for hydrogen storage. In this work, Mg-based nanocomposites
containing Fe and MgF2 were produced by reactive milling under hydrogen using the addition of
FeF3, or directly MgF2 and Fe. The efficiency of centrifugal and planetary mill in MgH2 synthesis
was compared. The phase evolution during different milling times (from 1 to 96 h) using the
planetary was investigated. The different H-desorption behavior of selected milled mixtures was
studied and associated with the different present phases in each case.
Hot Extrusion of Nanostructured Al Alloy Powder: Extrusion Ratio and Temperature Effect on the Microstructure and Mechanical Properties
Authors: Peres M.M. , Fogagnolo J.B. , Audebert Fernando , Saporiti F. , Jorge Alberto Moreira , Kiminami Claudio Shyinti , Botta Filho Walter José , Bolfarini Claudemiro
Published: March 2009

A nanostructured aluminium alloy powder, prepared by rapid solidification via gas atomization, was consolidated into bulk material under various processing conditions via hot extrusion. The microstructure modifications and mechanical properties of the consolidated alloys as a function of the extrusion conditions were investigated. The increase in the extrusion-load with the increase of extrusion-rate and decrease of temperature are shown and discussed in association with the modification in the microstructures. The differences in mechanical properties measured by compressive tests are also discussed in association with the extrusion parameters. Furthermore, suggestions are given for rationalising the extrusion ratio and temperature conditions for the consolidation of nanostructured aluminium alloy powders via hot extrusion.
Neutron Diffraction Measurement and Finite Element Modelling of Residual Strains Due to Bath and Spray Quenching of AISI 316L Stainless Steel Cylinders
Authors: Vorster Willem J.J. , van der Watt M.W. , Venter A.M. , Oliver E.C. , Korsunsky Alexander M.
Published: March 2009

This paper describes the thermo-elasto-plastic analysis of bath and spray quenched AISI
316L cylinders. A suitably detailed continuum deformation analysis approach presented here is
implemented within the framework of commercial Finite Element (FE) package ABAQUS. The results
of the numerical analysis are compared with the residual elastic strains measured experimentally using
neutron diffraction. The good agreement between measured and modelled residual elastic strains
provides a basis for careful analysis of the residual elastic strain development resulting from two
different quench methods. The conclusions drawn from the analysis provides a better understanding of
quench processsing, so that the effects of different heat removal efficiencies of such processing
technique can be taken advantage of to generate favourable residual elastic stress and deformation and
microstructural distributions with quench processed components.
Use of Stored Energy Distribution in Stochastic Vertex Model
Authors: Piękoś Krystian , Tarasiuk Jacek , Wierzbanowski Krzysztof , Bacroix Brigitte
Published: March 2009

The stored energy distribution versus crystal orientation in polycrystalline copper was
determined using synchrotron radiation. This distribution is an important input data for
recrystallization models. The stochastic vertex model of recrystallization was used in the present
work. It is a mixture of the classical vertex model and the Monte Carlo algorithm. Both grain
boundary energy and stored energy are taken into account in the calculations. In each elementary
step, a reasonably small, random modification of a given vertex position is generated and a
corresponding total energy change of a system is calculated. A new vertex position is retained with
a probability proportional to the Boltzmann factor. In such a way one avoids solving a complex
system of equations. This approach is also closer to the stochastic nature of recrystallization
process. The inclusion of the stored energy distribution in the above model enables a good
explanation of the recrystallization process. The recrystallization textures for polycrystalline copper
rolled to low and high reductions were predicted in agreement with experimental results.
Application of Synchrotron Radiation to Residual Stress Analysis by IP/cosα Method
Authors: Sasaki Toshihiko , Miyazawa Yohei , Takahashi Shunichi , Matsuyama Ryohei , Sasaki Katsunari , Hiratsuka Koichi
Published: March 2009

The X-ray stress measurement with synchrotron radiation (SR) and an image plate (IP)
was conducted using the facility of the Photon Factory (PF) of the High Energy Accelerator
Research Organization (KEK). The influence of 2θ on stress measurement with the cosα method
was investigated. The experiments were conducted under the conditions of 2θ=170 deg, 156.4 deg
and 127 deg respectively. It was found that the hypothesis on the relation between the accuracy and
the diffraction angle in the X-ray method is not valid in case of the cosα method.
X-Ray Powder Diffraction Characterization of Residual Stresses and Strains in Y3Al5O12:Nd3+ Nanoceramics
Authors: Fedyk Robert , Hölsä Jorma , Hreniak Dariusz , Lastusaari Mika , Lehto Vesa Pekka , Łojkowski Witold , Stręk Wiesław , Tenho Mikko
Published: March 2009

Y3Al5O12:Nd3+ nanoceramics were obtained by sintering nanocrystalline Y3Al5O12:Nd3+
powders at 450 oC under different pressures between 2 and 8 GPa. The structural purity, residual
stress, strain, texture, and crystallite size of the products were analysed with X-ray powder
diffraction. The results indicate that the average crystallite size remains unchanged at about 30 nm
in spite of the heating and the pressure applied. No texture was observed. On the other hand, the
microstrains increase with increasing pressure, while the residual stresses are at their maximum in
the green body and the sample processed at 8 GPa. Increasing strains were observed to increase the
width of the luminescence lines and to decrease the luminescence decay times.
Neutron Diffraction Studies of Residual Stresses in Functionally Graded Alumina/Zirconia Ceramics
Authors: Lukáš Petr , Vrána Miroslav , Vleugels Jef , Anné Guy , Van der Biest Omer
Published: March 2009

Graded Al2O3/Y-ZrO2 ceramics are developed to receive a construction material
combining favourable properties of both constituent components, alumina (low wear rate, high
hardness) and zirconia (high strength and toughness). The high performance of this material can be
reached by optimising the internal residual stress distribution resulting mainly from phase specific
stresses after cooling from the sintering temperature. For this purpose, non-destructive neutron
diffraction mapping of residual stresses has been employed. However, the application of the
conventional method does not provide straightforward results on macroscopic residual stresses. This
experimental technique uses the crystal lattice plane as a built in microscopic strain gauge and the
measured quantities are then lattice strains detected in each constituent phase separately. Based on
these experimental resources, the paper proposes a procedure of separation of the residual
macroscopic stress from phase specific stresses. The application of the presented method is
demonstrated on functionally graded materials (FGM) prepared by electrophoretic deposition
(EPD).
Residual Stress and Microstructural Variations in Thick Aluminium Alloy Forgings
Authors: Robinson Jeremy S. , Truman Christopher E. , Hossain M.S. , Wimpory Robert C.
Published: March 2009

The most critical stage in the heat treatment of high strength aluminium alloys is the
rapid cooling necessary to form a supersaturated solid solution. During cold water quenching of
thick sections, the thermal gradients are sufficient to cause inhomogeneous plastic deformation
which in turn leads to the development of large residual stresses. Two 215 mm thick rectilinear
forgings made from 7075 and 7010 were heat treated, and the through thickness residual stresses
measured by neutron diffraction and deep hole drilling. The distribution of residual stresses was
found to be similar for both alloys varying from highly triaxial and tensile in the core to a state of
biaxial compression in the surface. The 7010 forging exhibited significantly larger tensile stresses
in the core. 7075 is a much more quench sensitive alloy when compared to 7010. This results in loss
of supersaturation by second phase precipitation during quenching in the core of the 7075 forging.
Instrumented Indentation Testing on Uniaxially Prestressed Steel Samples
Authors: Gibmeier Jens , Scholtes Berthold
Published: March 2009

Instrumented indentation testing has been carried out on steel samples subjected to
uniaxial loading. It is distinguished between purely elastic as well as elasto-plastic loading up to
plastic strains of 3%. The experimental approach allows the combination of local in-situ residual
stress analyses by means of X-ray diffraction and the subsequent realisation of instrumented
indentation testing for the same material volumes beforehand irradiated by the X-rays. The aim of
the investigations was to explore a potential correlation between the imposed macroscopic
stresses and the characteristic values of instrumented indentation testing evaluated from the
measured force-indentation depth curves according to the standard ISO EN 14577. The studies
illustrate that results of depth sensing indentation testing have to be handled with care for
prestressed material states. The effect of mechanical stresses on the results of instrumented
indentation testing is not stringently limited on the hardness measures alone. Other indentation
parameters like e.g. the indentation modulus EIT or the elastic part of the indentation work η
IT are
likewise affected by the prestresses, whereas the impact is in the order of magnitude that it has to
be taken into account during interpretation of indentation readings.
Evaluation of the Residual Stresses and Determination of the Proportion of Residual Austenite in an Austempered Ductile Iron Having Undergone Thermo Mechanical Treatments
Authors: Labbe Eric , Serban Florin , Nicoară Mircea , Lodini Alain
Published: March 2009

The constant reduction of production costs and the development of materials during recent years are
favoured the development of Austempered Ductile Iron (ADI) because of favourable combination
of technological and structural properties. The process of forging on ADI makes it possible to
obtain final parts with good dimensions. Moreover, Austempered Ductile Iron has a remarkable
workability.
ADI has many advantages, including the possibility of modifying and of improving the
mechanical characteristics by thermo mechanical treatments while preserving a relatively low
production cost, thus competing with many categories of steels.
The study presented relates to the influence of the parameters of the thermo mechanical
treatments on the proportion of residual austenite allowing modification of the mechanical
characteristics of the material and on the evaluation of the residual stresses.
Hot Ductility of Fe-18Cr-12Mn-0.55N High Nitrogen Austenitic Stainless Steel
Authors: Shi F. , Wang Li Jun , Cui Wen Fang , Li Z.B. , Xu M.Z. , Liu Chun Ming
Published: March 2009

The hot ductility of Fe-18Cr-12Mn-0.55N high nitrogen austenitic stainless steel was
investigated in Gleeble-2000 thermomechanical simulator. The experimental results show that the
hot ductility curve of test steel is comprised of high-temperature brittlement region at the test
temperatures higher than 1150°C, high-temperature ductility region at the test temperatures from
850°C to 1150°C and middle-temperature half brittlement region at the test temperatures lower than
850°C. High-temperature brittlement and middle-temperature half brittlement are caused by the
appearances of δ ferrite and the precipitation of Cr2N phase at austenitic grain boundaries,
respectively, and the excellent hot ductility at test temperatures between the two brittlement
temperature regions results from the stable single phase austenitic microstructure.
Simulation of Intercritical Austenization of a C-Mn Cold Rolled Dual Phase Steel
Authors: Kuang Shuang , Kang Yong Lin , Yu Hao , Liu Ren Dong
Published: March 2009

Formation of austenite strongly influences the microstructures and mechanical properties
of dual phase steels. In present work, austenization process during intercritical annealing was studied
in a Fe-C-Mn steel using Gleeble-1500 thermal simulator and quantitative microscopy. The
experimental results show that austenite formation is separated into three different stages: (i) growth
of high carbon austenite into pearlite rapidly until pearlite dissolution is completed; (ii) slower
growth of austenite into ferrite; (iii) very slow equilibration between ferrite and austenite. The
thermodynamic and kinetic analyses show that growth of austenite into ferrite is controlled by carbon
diffusion in austenite in the primary stage and manganese diffusion in ferrite in the subsequent stage
because diffusion coefficient of Mn in ferrite is several orders of magnitude smaller than that of C in
austenite. The slow final equilibration between ferrite and austenite is obtained by manganese
diffusion through the austenite. Based on the analysis, one dimensional diffusion model of
intercritical austenization was developed and solved using finite volume method on the assumption
that solute flux was local balance at interface, and the kinetics calculated was compared with
experimental results. Simulated results indicate that growth of austenite reaches paraequilibrium in
about one second, but remains thousands of seconds to reach final equilibrium. Simulated
concentration profiles show that manganese atoms transferred from ferrite congregate in austenite
near phase interface, which is consistent with the experimental phenomenon.
Study on High Temperature Mechanical Properties of Bearing Steel GCr15
Authors: Zhu Li Guang , Lu Wen Gang , Han Yi Hua
Published: March 2009

Using Gleeble-3500 thermal simulation testing machine, the high-temperature
mechanical properties of GCr15 Bearing steel was tested. The zero plastic temperature (ZPT) and
zero strength temperature (ZST) were measured, so the optimum plastic temperature range and
brittle temperature range were fond. The appearances of fracture at different temperature were
analyzed by using scanning electronic microscope, and the fracture mechanism at different
temperature area of the steel was discussed. which was thought as the theoretical basis for
establishing the secondary cooling zone system of continuous casting.
Analysis of Worm Cutting Characteristics in Whirling Process
Authors: Lee Young Moon , Choi Won Sik , Son Jae Hwan , Oh Kyung Jun , Kim Sun Il , Park Geon Woo , Jung Hee Chul
Published: March 2009

The improved geometrical accuracy and better surface finish of worms are required,
especially in automobile industry. To meet this requirement, whirling process has been used in the
manufacture of worm. Whirling process is a cutting process in which a series of cutting edges on the
whirling ring remove material by turning over the rotating workpiece. In this study, cutting
characteristics of the worm in whirling process has been analyzed. The undeformed chip models of
front and side cutting edges were established. Using the undeformed chip models and DEFORM
software, cutting force analyses are carried out. The calculated cutting force imposed on the tool is
nearly the same as the sum of the forces calculated which are separately imposed on the front and side
cutting edges.
Finite Element Analysis on Microstructure Evolution of Hot Ring Rolling Process
Authors: Sun Zhi Chao , Yang He , Ou Xin Zhe
Published: March 2009

Hot ring rolling (HRR) is a 3D unsteady-state and coupled thermo-mechanical process, the
metal undergoes complicated unequal deformation and microstructure evolution. In this paper a 3D
rigid-plastic and coupled thermo-mechanical FEM model for hot ring rolling was developed based on
DEFORM3D platform, taking dynamic recrystallization (DRX) volume fraction, DRX grain size,
recystallization volume fraction and average grain size as objects, the mechanism of material
microstructure evolution and distributions in HRR process are thoroughly studied. The results show
that: with the HRR progressing, the DRX volume fraction, volume fraction, DRX grain size and
average grain size have the similar distributing characteristic, and the distribution zones expand from
a small local area into the whole ring strip, then diffuse to the mid-layer of ring with small
deformation, their distributions become more uniform. Meanwhile with increase of deformation, the
values of the DRX volume fraction and recrystallization volume fraction augment, i.e. the degree of
recystallization increases. The DRX grain size also augments due to local high temperature, while the
average grain size decreases. In general during HRR process the distributions of DRX volume
fraction, recrystallization volume fraction, DRX grain size, and average grain size are ununiform due
to unequal deforming in HRR process.
Finite Element Analysis of the Rolling Contact Fatigue Life of Railcar Wheels
Authors: Goo Byeong Choon , Seo Jung Won
Published: March 2009

Railcar wheels and axles belong to the most critical components in railway vehicles. The
service conditions of railway vehicles have been more severe in recent years due to speed-up.
Therefore, a more precise evaluation of railcar wheel life and safety has been requested. Wheel/rail
contact fatigue and thermal cracks due to braking are two major mechanisms of the railcar wheel
failure. One of the main sources influencing on the contact zone failure is residual stress. The
residual stress in wheels formed during heat treatment in manufacturing changes in the process of
braking. Thus the fatigue life of railcar wheels should be estimated by considering both thermal
stress and rolling contact. Also, the effect of residual stress variation due to manufacturing process
and braking process should be included in simulating contact fatigue behavior. In this paper, an
evaluation procedure for the contact fatigue life of railcar wheels considering the effects of residual
stresses due to heat treatment, braking and repeated contact load is proposed. And the cyclic stressstrain
history for fatigue analysis is simulated by finite element analysis for the moving contact
load.
Study on One Kind of Antenna Radomes Materials Numerical Algorithm Simulation Based on DBEM
Authors: Fang Ying Wu , Wang Yi
Published: March 2009

An approach of numerical modeling and simulation algorithm is presented to predict
dynamic behaviors of one kind of antenna radomes materials efficiently. Considering the dynamic
behaviors in the lateral and interior of the antenna radomes materials, the dynamic simulation
equations of the antenna radomes materials is established based on a dynamic boundary element
method (DBEM) by using the domain reducing to decrease computational scale and costs of the
equations greatly, and the dynamic behaviors of the antenna radomes materials can be gotten
effectively. Numerical simulation calculating and experiments show that the presented method not
only saves computational efforts, raises analytical efficiency and simulation accuracy but also can
provide the theoretical bases for avoiding the weak pose of the antenna radomes materials. It has very
important reference value for improving theoretical calculation and design level of the antenna
radomes materials.
Numerical Simulation and Structure Optimization of the Main-Control Reversing Valve of Electrical-Hydraulic Hammer
Authors: Du Shi Wen , Li Yong Tang
Published: March 2009

Based on viscosity hydrodynamics and hydro-finite element theory, flow field of the
main-control reversing valve of electrical-hydraulic hammer was simulated. The N-S equations
were discretized by the finite volume method. Hydraulic valve’s pressure and velocity distribution
were analyzed in the working process. Relationship between the structure of the flow field
(velocity, pressure, flow separation and reattachment, appearing and disappearing of vortices) and
the energy loss and component performance was proposed. The design of the hydraulic valve
structure was optimized which turns out to be high-efficiency and energy-saving
Finite Element Analysis of Slab Steel in the Process of Induction Heating
Authors: Mei R.B. , Li Chang Sheng , Han B. , Liu Xiang Hua
Published: March 2009

The induction heating process of slab steel had been discussed by finite element method.
The results obtained were in good agreement to the measured value. In addition, the low-frequency
induction heating process of slab steel was investigated and analyzed in detail according to the
practice requirements of a steel mill. During the heating process of slab steel by low-frequency
induction, the temperature increasing speed of surface is faster than that of center in initial time. With
the increment of heating time, the temperature increasing speed of surface becomes lower because of
the heat loss of boundary. A 90 percent of the slab steel temperature had risen from 1100°C to 1400°C
with 110Hz and 6.2×106A/m2 after 30min, which could be satisfied with heating requirements.
Mechanics Analysis and Numerical Simulation on the Precise Forming Process of Spline Cold Rolling
Authors: Li Yong Tang , Song Jian Li , Zhang Da Wei , Zheng Quan Gang
Published: March 2009

The forming process of spline cold rolling was analyzed. The unit average pressure,
contact area and rolling force in the cold rolling precision forming process were analyzed and
solved. The mechanical and mathematical model has been set up on the basis of the analysis. The
numerical simulation of spline cold rolling process was carried out. The results obtained by
comparison of theoretical analysis, numerical simulation and experiment provide a theoretical basis
for the study and application of spline cold rolling process.
Simulation of Gas-Solid Two-Phase Flow to Process of Filling the Foam Mould
Authors: Jiang Jun Xia , Wu Zhi Chao , Chen Li Liang
Published: March 2009

In lost foam casting (LFC), the foam pattern is the key qualification, and the filling
process is one of the crucial processes to ensure the high quality of the foam pattern. Filling without
uniformity and denseness will cause various defects and affect the quality of the surface. The
influential factors of filling process are analyzed .And optimizing filling process, enhancing
efficiency, decreasing waster are obtained by the numerical simulation of filling process using
computer.
The governing equations of the dense compressible gas-solid two-phase flow are established,
and the physical signification of each one in the equations is discussed. The filling process is solved
by Euler- Euler model. In the simulation, the volume of foam bead in every governing unit at
different time is calculated, and the trend of foam bead flow is obtained.
The filling process of various different conditions is simulated, considering different shooting
methods and the position of baffles, and recorded by digital vidicon. The characteristics and the
rules of the process are summarized. By contrasting the result of the numerical simulation with the
one of examination, it is found that the fluid trend of foam bead in the numerical simulation is
accordant to the actual process. So the numerical simulation of filling process by applying this
model is an effective method.
Fast Prediction of Springback at Product Design Stage for Sheet Metal Forming
Authors: Zhang Zhi Bing , Liu Yu Qi , Du Ting , Li Zhi Gang
Published: March 2009

A novel hybrid method is proposed in the paper, which is an assistant tool for product
designers to estimate springback in sheet metal forming process at the preliminary design stage. In the
hybrid method, the forming results are obtained firstly by an inverse finite element approach (IA) with
a membrance element. The thickness strain and stress can be calculated according to the approximate
curvature radius of the discrete meshes. Then, a rotation-free shell element is employed, with only
three displacements at the corner nodes of the element, to calculate the springback. To verify the
accuracy and efficiency of the hybrid method, the numerical results of the hybrid method on two
benchmark tests are compared with experimental results.
The Application of Welding Heat Cycle Computer Software
Authors: Feng Ying Ying , Luo Zong An , Zhang Dian Hua , Wei Jin , Wang Li Jun
Published: March 2009

Welding heat cycle computer software is developed successfully, bases on experiential
and practical mathematic model, uses LabVIEW7.1 to program, it can draw single or multi-process
welding heat cycle curve conveniently and quickly. This paper puts emphasize on explaining the
realization of multi-process heat cycle curve which is drawn by the same or different mathematic
model, and the research of heat cycle curve’ change which is caused by the change of parameters. It
introduces the comparison between practical curve which is obtained from experiment and settled
curve after this software is embedded in MMS-200 thermo-mechanical simulator. The development
of this software has important value on the research of welding process, fills up the blank of
domestic thermo-mechanical simulator at the aspect of welding thermo-simulation, consummates
the function of thermo-mechanical simulator, and broadens its applying field further.
Optimization Design for the Interface Modulus of Csf/Al Composite
Authors: Tang Guo Xing , Zhang G.A. , Wu H.B. , Tian Wen Tong , Guo Hun
Published: March 2009

Short fiber reinforced Al-base composite can be manufactured various parts by plastic
working. Elastic modulus has a large influence on the parts among the composite system. In the
paper, model of finite-element analysis has been established. The influences of interface modulus on
the law of stress-strain distribution, the strength and the modulus for the composite materials have
been simulated by ANSYS in the condition of strong-bond, medium-bond and weak-bond interface.
The results show that the stress-strain distribution is non-uniform, moreover the force on the fiber is
greatly higher than that of the matrix within the composite materials; the strength of the composite
materials is improved with the increasing of the interface modulus, but the increasing will be limited
by the strength of fiber. Therefore the relation of ideal interface modulus with the fiber strength has
been proposed. 70GPa of the interface modulus is thought to be better for M40 short fiber.
High Temperature Mechanical Behavior of 16Mnq under Constant Constraint Conditions
Authors: Gao Yi , Pan Zeng
Published: March 2009

Welding is a main processing way in the manufacture of steel bridges. Welding
deformation is one of the main influencing factors on the quality of steel bridges, which relates to the
effect of material mechanical behavior and welding techniques. The welding distortion is considered
to be a result from the inherent strain after welding, which dependent on the highest temperature
reached and the constraint at each point. 16Mnq is a common structural steel used in railway steel
bridges. Thus, the paper addresses the high-temperature mechanical behavior of 16Mnq through a
series of experiments under various peak temperatures and constant constraint conditions.
Relationships between temperature, constraint and strain at high temperatures were discussed. The
yielding phenomenon based on high temperature occurs under a certain condition of both constraint
and temperature, and this phenomenon had significant influence on the inherent strain. The results are
significant to understand thermal-mechanical behavior of material and to predict the inherent strain
under constant constraint conditions during heat circulates of welding.
Phase Formation and Structure of Mullite-Alumina-Zirconia and Spinel-Enstatite Ceramics Developed from Synthetic and Mineral Raw Materials
Authors: Sedmale Gaida M. , Sperberga I. , Hmelov A. , Sedmalis U. , Actins A.
Published: March 2009

New dense and porous ceramics are developed using two formulation approaches. These
are ceramics with remarkable content of mullite, corundum and ZrO2 - tetragonal and monoclinic in
crystalline phase and porous (average size of pores up to 150-350μm) spinel-enstatite/forsterite
ceramics. To promote the phase development by high-temperature synthesis of these ceramics the
mineral raw materials – illite clay and illite clay together with dolomite are used.
Bulk density for mullite (corundum) – zirconia ceramics is increased by equal addition of illite clay
(8.2 wt.%) as well as ZrO2 and especially ZrO2 +Y2O3 to starting mullite mixtures. Contrary the
addition of different kind and amount of illite clay together with dolomite trends to formation of
spinel – enstatite (forsterite) ceramics and decrease the bulk density to the value up to 0.35 g/cm3.
The XRD results indicate that ZrO2 monoclinic/tetragonal incorporation in mullite (corundum)
structure realizes through the liquid phase. Development of the spinel MgAl2O4 and enstatite
MgSiO3 crystalline phases along with the sufficient amount of glassy phase in microstructure and
even distributed pores are proper for spinel-enstatite (forsterite) ceramic samples.
Microstructure and Mechanical Properties of Nanostructured Metals Produced by High Strain Deformation
Authors: Kamikawa Naoya , Zhang Hong Wang , Huang X. , Hansen Niels
Published: March 2009

Deformation structures produced by high pressure torsion (HPT) and accumulative
roll-bonding (ARB) were characterized by transmission electron microscopy and electron backscatter
diffraction, and the mechanical properties of the ARB samples were determined by uniaxial tensile
testing. The structural evolution during HPT in high purity nickel has been examined and an extended
lamellar boundary structure was observed at high strains. For ARB samples deformed to high strains,
an almost similar structural morphology has been observed in both interstitial free steel and in
commercial purity aluminum, whereas a relatively equiaxed structural morphology was observed in
high purity aluminum samples. In all samples, both deformed by HPT and ARB, the deformation
structures were composed of a large fraction of high-angle boundaries, together with low-angle
boundaries and isolated dislocations between the boundaries. Common characteristics have been
identified in the mechanical behavior of the ARB samples, namely a very high strength, a small
uniform elongation and a relatively large post-uniform elongation after necking. For HPT and ARB
the structural morphology and structural parameters are compared, and for the ARB samples
structure-property relationships are also discussed.
Mechanical Properties of Nanocrystalline Materials Produced by In Situ Consolidation Ball Milling
Authors: Koch Carl C. , Youssef Khaled M. , Scattergood Ron O.
Published: March 2009

This paper reviews a method, “in situ consolidation ball milling” that provides artifactfree
bulk nanocrystalline samples for several ductile metals such as Zn, Al and Al alloys, and Cu
and Cu alloys. The preparation method is described in this paper and examples of the mechanical
behavior of nanocrystalline materials made by this technique are given. It is found that in such
artifact-free metals, combinations of both high strength and good ductility are possible.
Surface Nanocrystallization by Surface Mechanical Attrition Treatment
Authors: Tao N.R. , Lu Jian , Lu K.
Published: March 2009

Based on strain-induced grain refinement, a novel surface mechanical attrition treatment
(SMAT) technique has been developed to synthesize a nanostructured surface layer on metallic
materials in order to upgrade their overall properties and performance without changing their
chemical compositions. In recent several years, the microstructures and properties of surface layer
were systematically investigated in various SMAT metals and alloys, including b.c.c., f.c.c. and h.c.p.
crystal structures. Different grain refinement approaches and nanocrystalline formation mechanisms
were identified in these deformed materials, involving dislocation activities, mechanical twinning and
interaction of dislocations with mechanical twins. The properties of the surface layer were measured
by means of hardness, tensile, fatigue and wear tests. The enhanced properties of the surface layer are
mainly attributed to the strain-induced grain refinement. In this work, we reviewed the
microstructures and properties of surface layer in the SMAT materials.
Analysis on Thermal Strain of AC7A Aluminum Alloy Casting Mold for Automobile Tire by Finite Element Method
Authors: Choi Je Se , Oh Yool Kwon
Published: March 2009

In the present study, AC7A aluminum alloy casting mold which consist of 8 pieces is
introduced as an analysis model. Also, numerical work using a finite element method was applied to
investigate the thermal strain that included the temperature distribution, stress and strain during the
cooling process in AC7A casting mold. In addition, the numerical work was carried out that analysis
results of the AC7A casting mold were compared with those of mild steel casting mold to prove the
improvement and good quality. The numerical results such as temperature distributions, stress and
strain are presented to help to make the effective and the best tire mold. In addition, the introduced
technique of numerical work using a finite element method is very useful and especially needs to
improve the precision of tire mold such as sectional type or puzzle type.
Study on Induction Spontaneous Heating Reflow
Authors: Xu Hong Bo , Li Ming Yu , Kim Jong Myung , Kim Hong Bae , Kim Dae Won
Published: March 2009

The focus of this study was on discussing the novel reflow method ISHR (Induction
spontaneous heat reflow) used for high-density area array packaging and assembly. Multi-layer
under bump metallization (UBM) and Sn3.5Ag lead-free solder ball were laid in the high frequency
electromagnetic field. Because of the induction heating, solder balls melted and spread onto the
UBM to form solder bumps. The solder bumps could be formed within 2 seconds through this
method; meanwhile, the infrared temperature measurement results showed that the rosin substrate
temperature was lower. The shear test indicated that the solder bumps made by ISHR can satisfy the
mechanical requirement. Finally, the feasibility experiment was performed to demonstrate the
application feasibility of this ISHR technology. Through all these experiments, conclusion can be
made that the ISHR as a novel reflow method can be applied in microelectronics packaging.
Reproducing the Shilla Dynasty’s Direct-Bonding Granulation Process
Authors: Song Oh Sung , Kim Jong Ryul , Kim Myung Ro
Published: March 2009

Granulation is a precious metal craft process method that decorates a metal surface using tiny
metal granules. It was imported into Korea during the Shilla Dynasty around 1500 years ago, and
many granulation ornaments have been found with the process’s unique bonding features. The
granules show a direct bonded interface with a neck. The key technology of making granules and
bonding the granules is not well known. Thus, it is a technology of the Lost World. Although the
exact bonding method is unidentifiable, it is known that the traditional method of preparing gold
granules was time consuming and costly. Therefore, we proposed a process to reproduce the Shilla’s
granulation ornament using a modern method. First, we employed atomization to produce 22K gold
granules. Direct bonding was accomplished using a spot welder and vacuum jig instead of using the
traditional method of graphite bed melting and direct annealing. 0.8 mm granules were successfully
fabricated and bonded directly to the substrate with a necking and 35% bonding ratio, which is very
similar to Shilla’s granule bonding. Moreover, to estimate the bond strength, K factors (fracture
toughness index) at different bonding ratios were evaluated using a finite element method
simulation. Our proposed direct bonded granule process and design were expected to have enough
bond strength to be used as a key element for fine modern jewelry.
High Dissolution Rate of Solid Materials in Molten Lead-Free Solders
Authors: Takemoto Tadashi
Published: March 2009

Sn-based lead-free solders have some characteristics that are different from the
conventionally used Sn-Pb eutectic. One is the high dissolution rate of metals and alloys into
molten lead-free solder. Several problems due to this high dissolution rate were reviewed. The
prominent materials that suffered from this high dissolution rate are copper and iron based. High
dissolution rate of Cu resulted in thick Cu-Sn intermetallic compound formation during soldering
and Cu enrichment in wave soldering bath. The iron-based materials used for soldering
equipments are damaged by erosion. Suppression of the dissolution rate is important to secure
quality of micro-soldered joints, to prevent contamination of solder bath and to prolong the life of
soldering equipments. The method of suppressing dissolution in practical soldering operation and
some examples of erosion damage are introduced.
Characteristic of Electrochemical Migration on Flexible Printed Circuit Board
Authors: Noh Bo In , Lee Jong Bum , Lee Bo Young , Jung Seung Boo
Published: March 2009

The electrochemical migration (ECM) with flexible printed circuit board (PCB) was
affected by factors such as distance between the electrodes and bias voltage using water drop (WD)
test. The rate of migration was increased by decreasing the distance between electrodes of the
opposite polarity and increasing the bias voltage.
Computer Simulation of Wetting and Flowing Behaviors of Filler Metal during Laser Brazing Process
Authors: Saida Kazuyoshi , Song Woo Hyun , Nishimoto Kazutoshi
Published: March 2009

The wetting and flowing behaviors of the filler metal during laser brazing
process were analyzed by the computer simulation. Two situations of the wetting and
flowing during laser brazing were modelled, i.e., the metled Au-18%Ni and Ag-10%Pd filler
metals on the butt joint of Inconel 600, and the melted Cu-8%Sn filler metal on the
dissimilar butt joint of type 304 stainless steel to Cu. The filler metal droplet wetted and
spread on the base metals and simultaneously infiltrated into the joint gap with the lapse of
time. The Au-Ni and Ag-Pd filler metal infiltrated into the 0.3mm wide joint gap at the
completion of brazing even in the single beam brazing. The Au-Ni filler metal did not infiltrate
into the joint gap completely at the brazing clearances of 0.1-0.2mm in the single
beam brazing, however, it could be filled up in the joint gap in the tandem beam brazing.
The Cu-Sn filler metal wetted on the both base metals of stainless steel and Cu and filled
up the 0.3mm wide joint gap when the location of preheating beam deviated in 0.5mm to
Cu substrate, however, it did not infiltrate into the joint gap completely at the deviation
distance of preheating beam to Cu substrate being 1.0mm. It followed that the wetting
and flowing behaviors of the filler metal during laser brazing process could be predicted by
the computer simulation.
Finite Element Analysis of Hybrid Rotary Friction Welding and Investigating the Effects of Pressure on Variations of Temperature and Strain Values
Authors: Habibi-Parsa Mohammad , Davari H. , Hadian A.M. , Nili-Ahmadabadi Mahmoud
Published: March 2009

Hybrid Rotary Friction Welding is a modified type of common rotary friction welding processes. In
this welding method, parameters such as pressure, angular velocity and time of welding control
temperature, stress, strain and their variations which play an important rule in defining optimum
process parameter combinations in order to improve the design and manufacturing of welding
machines and quality of welded parts. Thermo-mechanical simulation of friction welding has been
carried out. It has been shown that simulation is an important tool for prediction of generated heat
and strain at the weld interface and can be used for prediction of microstructure and evaluation of
quality of welds. For simulation of Hybrid Rotary Friction Welding a commercial finite element
program has been used and the effects of pressure on temperature and strain variations have been
investigated.
Experimental and Numerical Studies of the Effects of Process Parameters in the Continuous Friction Welding Process
Authors: Mousavi Seiyed Ali Asghar Akbari , Kelishami A. Rahbar
Published: March 2009

All of the experiments performed on friction welding combinations of 304SS and mild
steel are modeled using the ABAQUS code and the Johnson-cook equation is used to define
coupled thermo-mechanical properties of materials. The variations of temperature, von-Mises
stress, plastic strain, and strain rate during continuous welding are systematically investigated and
analyzed. The calculated results of temperature distribution are in good agreement with the infrared
detected ones. The numerically calculated results for the shape of the welded joint also show an
excellent fit with experimental observations. The von-Misses stress and equivalent strain
distributions are more influenced by the initial pressure than the final pressure. The
metallographical examinations, hardness and tensile tests of the samples are carried out. In all the
tension tests carried out the samples were broken from their base metals and not the welds.
An Evaluation Approach for Prediction of Process Parameters with Genetic Algorithm
Authors: Thao D.T. , Kim Il Soo
Published: March 2009

Gas Metal Arc (GMA) welding process has widely been employed due to the wide range
of applications, cheap consumables and easy handling. A suitable mathematical model to achieve a
high level of welding performance and quality should be required to study the characteristics for the
effects of process parameters on the bead geometry in the GMA welding process.
The objective of this paper is to present development of three empirical models (linear,
curvilinear and intelligent model) based on full factorial design with two replications to estimate
process parameters on top-bead width in robotic GMA welding process. Regression analysis was
employed for optimization of the coefficients of linear and curvilinear models, but Genetic
Algorithm (GA) was utilized to estimate the coefficients of intelligent model. ANOVA analysis
using experimental data were carried out representation of main and interaction effects between
process parameters on top-bead width. Resulting solutions and graphical representation showed that
the developed intelligent model can be used for prediction on top-bead width in robotic GMA
welding process
Computer Simulation of Residual Stresses in Welding Process Using Finite Element Method
Authors: Li Shou Ju , Liu Ying Xi , Cao Li Juan , Shangguan Zi Chang
Published: March 2009

The prediction procedures of the residual stresses in welding process were presented by
using finite element techniques. Owing to localized heating by the welding process and subsequent
rapid cooling, the residual stresses can arise in the weld itself and in the base metals. The bilinear
elastic-plastic material model based on Von Mises yield criterion was developed. The material nonlinearity
of weldment and welding fluid was dealt with using an incremental technique. Inside each
step, the Newton-Raphson iteration method was utilized. A fully coupled thermo-mechanical twodimensional
analysis was performed with finite element method. The model applied in this study
adopts the technique of element birth and death to simulate the weld filler variation with time in
multi-pass welded joints. The effects of welding speed on residual stresses are discussed.