bluuebunny/crossref_metadata_2025 huggingface dataset:
Neutron Strain Investigations of Laser Bent Samples
Authors: Venter A.M. , van der Watt M.W. , Wimpory Robert C. , Schneider Rainer , McGrath P.J. , Topic M.
Published: March 2009

Bending of metal plates with high-energy laser beams presents a flexible materials
forming technique where bending results from the establishment of a steep temperature gradient
through the material thickness. This inevitably leads to non-uniform thermal expansion/contraction
and subsequently residual stresses. Non destructive residual strain mapping with neutron
diffraction through the 8mm thickness of a series WA 300 grade structural steel plate samples,
focused on the region straddling the centerline of the heating bead location, shows the presence of
large residual stress fields. Directly below the laser track the longitudinal strains are tensile and
dominant, normal strains compressive and transverse strains slightly tensile. The magnitudes of the
strains decrease outside the width of the laser beam footprint. The first laser pass induces throughthickness
strains close to yield, whereafter their magnitudes decrease with increased number of laser
beam passes. A comprehensive mapping of the longitudinal stresses as function of the number of
laser passes is given.
Advanced Gate Dielectric Development for VLSI Technology
Authors: Ma Yi
Published: March 2009

In this paper, gate dielectric scaling with nitrogen incorporation technologies is reviewed.
In key technologies such as thermal nitridation, oxide/nitride stacked dielectric structure and
nitrogen implant/plasma played fundamental role in advance of semiconductor industry. Besides the
technologies, primary integration schemes and their impacts on device performance and reliability
are also covered.
Investigation of Ultra Thin Thermal Nitrided Gate Dielectrics in Comparison to Plasma Nitrided Gate Dielectrics for High-Performance Logic Application for 65nm
Authors: Trentzsch Martin , Golz Christian , Wieczorek Karsten , Stephan Rolf , Mantei Tilo , Bayha Boris , Ohsiek Susanne , Raab Michael , Nényei Zsolt , Lerch Wilfried , Niess Jürgen , Dietl Waltraud , Kirchner Christoph , Roters Georg
Published: March 2009

In this work we present a comprehensive comparison of ultra thin thermally nitrided
(TN) to plasma nitrided (PN) gate dielectrics (GD). We will show that thermal nitridation is a
promising technique to increase the nitrogen concentration up to 25%. Furthermore, we will
demonstrate that ultra thin thermally nitrided GD have the potential to be an alternative solution
compared to plasma nitrided GD. This work includes the analysis of physical and electrical
parameters as well as reliability results from reliability characterization. Additionally, we
investigated the impact of Deuterium on electrical parameters and reliability behavior.
Evolution of Commercial RTP Modules
Authors: Peuse Bruce
Published: March 2009

Rapid Thermal Processing (RTP) has been a key technology for semiconductor
manufacturing. The ability to rapidly change wafer-processing temperature in a well-controlled way
is a distinguishing characteristic of RTP. Today’s state of the art single wafer RTP equipment is
used for a wide range of thermal processes for the manufacturing of advanced semiconductor
devices. Two different designs of halogen lamp based RTP equipment dominate the applications.
The two equipment designs can be traced back to the early development of the semiconductor
industry before there was wide acceptance of RTP. Two junctures in the evolutions of these designs
resulted in the growth of RTP. The first juncture occurred when the conventional batch diffusion
furnace could not satisfy some of the thermal budget and ambient control process requirements for
semiconductor devices. A second juncture occurred with breakthrough developments in RTP
equipment that enabled better control and repeatability of the process temperature. Developments of
alternatives to tungsten halogen lamp based RTP will likely be seen in the future.
Modeling and Simulation of Advanced Annealing Processes
Authors: Martinez-Limia Alberto , Pichler Peter , Steen Christian , Paul Silke , Lerch Wilfried
Published: March 2009

In this contribution we illustrate some important features of the development of models
for the simulation of advanced annealing processes. Taking arsenic as example we discuss the challenges
that the last technology trends represent for process modeling. Issues like shallow implants,
high doses, low total thermal budgets, and steep temperature profiles are discussed, highlighting the
physical phenomena to take into account, and how to design models that reproduce them. We also
discuss with examples how important are the critical evaluation of known parameters and established
approaches, and the extraction of parameters from experiments. Finally we show some applications
of our model for spike and flash annealing of arsenic implants.
Ultra-Rapid Thermal Process for ULSIs
Authors: Suguro Kyoichi
Published: March 2009

This paper reports on the ultra-rapid thermal annealing of next generation MOSFETs. In
ultra-rapid thermal annealing, the most important issue is to achieve a good balance between
electrical activation and impurity diffusion. Another issue of annealing implantation damages is
also discussed: Optimized annealing combined with millisecond annealing and conventional
halogen lamp annealing is necessary for annealing out defects at end-of range region. Application
possibilities of millisecond annealing for deep junction activation and oxidation are also discussed.
Model Based Measurement in Advanced Rapid Thermal Processing
Authors: Merkl Christoph , Bremensdorfer Rolf
Published: March 2009

Temperature measurement by means of a pyrometer is affected by changes in the
background illumination. Physical modeling is a very effective method to discern the origin of
radiation contributions and separate the thermal radiation emitted by the object of interest from
parasitic radiation. An observer algorithm making use of physical models was successfully applied
to infrared pyrometry for rapid thermal processing. Rapid thermal processing is characterized by fast
temperature changes in the range of several hundred degree per second. The heating source typically
emits light within a broad wavelength band ranging from visible to infrared. Especially in rapid
thermal processors that apply heat to both sides of a silicon wafer, this light is partially picked up by
the pyrometer sensor. As a consequence these types of systems require methods to handle the fast
changing radiation contribution of the heating source to the pyrometer signal.
Short Time Thermal Processing: From Electronics via Photonics to Pipe Organs of the 17th Century
Authors: Skorupa Wolfgang
Published: March 2009

There is a clear and increasing interest in short time thermal processing far below one
second, i.e. the lower limit of RTP (Rapid Thermal Processing) called spike annealing. It is the
world of processing in the millisecond or nanosecond range. This was driven by the need of
suppressing the so-called Transient Enhanced Diffusion in advanced boron-implanted shallow pnjunctions
in the front-end silicon chip technology. Meanwhile the interest in flash lamp annealing
(FLA) in the millisecond range spread out into other fields related to silicon technology and beyond.
This paper reports shortly about the restart in flash lamp annealing of the Rossendorf group in
collaboration with the Mattson group and further on recent experiments regarding shallow junction
engineering in germanium, annealing of ITO (indium tin oxide) layers on glass and plastic foil to
form an conductive layer as well as investigations which we did during the last years in the field of
wide band gap semiconductor materials (SiC, ZnO). Moreover recent achievements in the field of
silicon-based light emission basing on Metal-Oxide-Semiconductor Light Emitting Devices will be
reported. Finally it will be demonstrated that the basic principle of short time thermal processing,
i.e. surface heating on a colder bulk, features also advantages regarding the casting of lead sheets to
produce organ pipes in the spirit of the 17th century.
Effects of Gas Multicomponent Thermochemical Treatment Process on Structure and Properties of Steel 20
Authors: Zhou Hai , Chen Fei , Yang Ying Ge , Wan Han Cheng , Chen Jia Qing , Yao Bin , Xi Ming
Published: March 2009

By low temperature gas multi-component thermochemical treatment, C, N, and O three elements are
simultaneously infiltrated into the surface of steel 20, forming a dense, homogeneous, 50μm
penetrating layer and about 150μm transition layer. X ray diffractometer and sweep electron
microscope are used to measure the phase components and surface morphology. The results show that
the penetrating layer is mainly composed of oxides and nitrides. After gas multi-component
thermochemical treatment, the hardness on the surface penetrating layer of steel 20 may reach up to
over 800HV, 3 times more than that of the original material; the hardness of transition layer is about
300HV, also higher than that of the original material. Within the temperature range of the test, the
surface hardness increases with the rise of heating temperature, and the thickness of penetrating layer
also increases with the rise of temperature. The tribological experiment shows that after
multi-component thermochemical treatment, the lowest friction factor of steel 20 is 0.25, while the
friction factor of the original material is 0.5; the wear resistance was improved.
Achieving the Dual Phase Structure in Low Alloyed Steel with Slow Cooling Rate
Authors: Jäppinen Tarja , Kivivuori Seppo
Published: March 2009

In steel wire processing it is difficult to reach a homogenous structure throughout the cross-section
of the wire particularly in greater diameters. One alternative for producing a homogenous
structure is to find a cooling path with a wide transformation temperature range. Fully austenite
steel wire rolled at high temperatures can be decomposed into ferritic-martensitic dual phase
structure using relatively slow cooling rates. Test materials were low alloyed low carbon steels
with variations in alloying elements. Gleeble-1500 thermomechanical simulator was utilised to
study the effect of cooling rate on decomposition of austenite after deformation. The
microstructures were studied with an optical microscope.
In certain low alloyed steels slow cooling rates eliminate the bainite transformation and
instead martensite is formed. The final microstructure depends mainly on the carbon content but
also on the amount of other alloying elements and their effects on the austenite phase.
Research on the Mechanisms of Laser Forming for the Micro-Structural Element
Authors: Jin Ying , Wu Jian Hua , Shi Yong Jun , Shen Hong , Yao Zheng Qiang
Published: March 2009

Laser forming of a micro-structural element involves a complex thermoplastic process.
Numerous efforts had been made on the mechanisms of laser forming for macro-size elements, such
as temperature gradient mechanism, buckling mechanism and upsetting mechanism, etc. It is found
that the three mechanisms cannot depict fully the process of deformation in the macro-size element
forming, let alone meet the needs of the micro-size one. Considering the laser inducing thermal
stresses with size factors differing from the conventional analysis, it is essential to reveal the
mechanisms dominating the forming process to accurately control the bending angle of a tiny plate.
By studying the thermal transfer and elastic-plastic deformation of micro-structural element laser
forming, the forming mechanism is explained within the micro size. The finite element model for
laser bending is constructed for simulation. The stimulation results are agreement with the
experimental data.
Study on Healthful Function of Superheated Water Extractives of Phyllostachys Heterocycla by GC/MS
Authors: Ma Qing Zhi , Peng Wan Xi , Zhang Dang Quan , Liu Qi Mei , Wu Yi Qiang
Published: March 2009

The chemical components from superheated water extractive of fresh Phyllostachys
heterocycla shavings were separated and identified by GC/MS after enriched. Relative content of
each component was determined by area normalization. 31 compounds representing 99.99% of the
extractives were identified. The main and abundant constituents were as: heptacosane (35.37%),
2,2,4-trimethyl-3- (3,8,12,16-tetramethyl-heptadeca-3,7,11,15-tetraenyl)-cyclohexanol (16.25%),
isochiapin B (12.24%), tetradecane, 2,6,10-trimethyl- (cas) (7.59%), dibutyl phthalate (5.66%),
etratriacontane (cas) (4.89%), 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester (cas) (3.74%),
phosphoric acid, tributyl ester (cas) (2.92%), silicone polymer (2.47%), silicate anion tetramer
(2.43%), 2,3-dihydro-benzofuran (2.01%), quercetin 7,3',4'-trimethoxy (1.04%), 1-heptatriacotanol
(0.98%) and so on. Most components of superheated water extractives of fresh Phyllostachys
heterocycla are abundant and healthy to human, indicating that there are natural health elements in
Phyllostachys heterocycla.
Calculation on Temperature Rise of CMP Process: Roughness Effects Considered
Authors: Ye Wei , Zhang Chao Hui
Published: March 2009

Chemical mechanical polishing (CMP) has been widely accepted in modern integrated
circuit (IC) industries and hard disk manufacturing processes, to insure wafer surface with high level
of global and local planarity required. In CMP process, temperature rise has two-edged influences:
temperature-rise accelerates the chemical activity and the motion of nano-particles contained in the
slurry through which material removal ratio (MRR) is enhanced; the other side of the same coin is,
however, that it will soften the pad surface and subsequently reduce the MRR. Furthermore, it is
found that temperature-rise would cause agglomeration of nano-particles, which would cause the
wafer surface defect. The net effects of temperature thus should be under investigation with scrutiny.
In an attempt to study the temperature variation and influencing rule, in this paper we firstly establish
the flow equation considering pad roughness, coupling the energy equation on the basis of
thermodynamics. Then, by taking numerical simulation which is carried out to give out the
temperature distribution of conventional CMP process. The results show that temperature-rise in the
CMP process is very minor. The research will surely shed some lights on the mechanism of CMP and
lay a feasible foundation for possible future utilization.
Research on Hydrogen Induced Cracking of 08Cr2AlMo Steel Based on the Empirical Electron Theory
Authors: Gu Bo Qin , Zhang Yao Feng , Ding Yi
Published: March 2009

Hydrogen induced cracking (HIC) is one of main type of damage to metallic materials in
H2S solution. 08Cr2AlMo steel is a type of material developed especially for heat exchanger pipe
bundle used under H2S condition in recent years. Calculation models of the construction units in
08Cr2AlMo steel with or without hydrogen were established based on the empirical electronic
theory in solid (EET) and valence electron structure of the construction units in this steel was
calculated. The results show that hydrogen bond is formed between the hydrogen solved in the steel
and other atoms in the steel. The cleavage energy of crystal plane with hydrogen bond is increased
and that without hydrogen bond is decreased. Hydrogen results in the remarkable difference of the
cleavage energy of different crystal planes and changes the bond distribution in the structure units.
The mechanical property of the units has directional properties. In these units, the microcracks
propagate along the cleavage plane with small binding energy and so the brittle fracture of the
crystal occurs. The elements of Cr, Al, Mo are able to strengthen the basal body without carbon,
and have little effect on the plastic nature. In the structure unit with carbon, carbon increases the
anisotropy of mechanical property and alloying agents decrease the plastics of the steel further. The
alloying agents of Cr and Mo decrease plastic nature loss of the steel due to decrement of the
anisotropy of mechanical property in the unit with hydrogen. The alloying agent of Al has little
effect on the loss of plastic nature.
Development and Application of Experimental Facilities for Steel Forming
Authors: Luo Zong An , Wang Guo Dong , Liu Xiang Hua , Li Jian Ping , Wang Li Jun , Hua Fu An
Published: March 2009

In order to meet the demand of steelmakers, series of experimental facilities such as
thermo-mechanical simulator, pilot hot rolling mills, controlled cooling system, pilot cold rolling
mills, simulator for continuous annealing of strips, and hot-dip galvanizing simulator have been
developed and applied by the RAL. These instruments can be used to simulate different processing
technologies of steel forming which include continuous casting, hot rolling, controlled cooling, cold
rolling, annealing and surface treatment(such as coating), etc. They provide unique research means
for the R&D activities of China’s iron and steel industries. The characteristics, experimental
functions, performance parameters and application of these facilities are introduced in the paper.
Numerical Simulation of Solidified Structure Formation of Al-Si Alloy Casting Using Cellular Automaton Method
Authors: Ohsasa Kenichi , Matsuura Kiyotaka , Kurokawa Kazuya , Watanabe Seiichi
Published: March 2009

For the purpose of the prediction of casting structures, heterogeneous nucleation rate in the
undercooled melt of solififying Al-Si alloys were evaluated by comparing experimentally observed
macrostructures of solidified ingots with numerically simulated ones. Molten alloys were
unidirectionally solidified in an adiabatic mold from a steel chill block located at the bottom of the
mold. In the experiment, columnar to equiaxed transition (CET) was observed. A numerical
simulation for grain structure formation of the sample ingots was carried out using a cellular
automaton (CA) method, and heterogeneous nucleation rate in the solidifying alloys were evaluated
by producing the similar structures to experimental ones. An attempt was made to predict the grain
structure of conventionally cast ingots using the evaluated heterogeneous nucleation rate. However,
the simulation could not predict the structure of ingot with low superheat due to crystal
multiplication near the mold wall. The crystal multiplication mechanism, so-called "Big Bang
mechanism", was introduced into the simulation and the simulation could predict the grain
macrostructure composed of columnar and equiaxed crystals that were similar to experimentally
observed one.
The Computer Solidification Simulation of Oceangoing Freighter Rudder Horn
Authors: Xie Jing Pei , Wang Ai Qin , Wang Wen Yan , Li Ji Wen , Zhang Hui Min , Hou Jin Ling
Published: March 2009

The numerical solidification simulation for oceangoing freighter rudder horn steel casting
has been made and the location and reasons forming casting defects have been predicted by
HUAZHU CAE software. Simulating result shows that the casting perfects can be realized by means
of the technological optimization and rationally assembling gating system, risers and iron chill. After
magnetic particle detection and ultrasonic inspection, the properties and microstructure of the
oceangoing freighter rudder horn steel casting are in accord with the standard of USA, Germany and
Japan.
The Application on Initial Design of Auto Panel Based on One-Step FEM
Authors: Deng Zhao Hu , Huang Yu Ping , Zhang Yan Qin , Ruan Feng
Published: March 2009

At the early stage of product design, the information about mould, blank and boundary
condition are not definite. It is difficult to calculate with incremental method. For solving this
problem, one-step finite element method(FEM) was put forward in recent years. It starts from
product shape, takes it as the middle plane of formed part, disperses it and determines the location
of nodes in initial blank at certain boundary conditions with finite element method. Then the
corresponding blank shape can be obtained by one-step FEM. In this paper it is discussed that the
basic theory of one-step FEM and the research of the key technology. And it is simulated the
pressing of auto panel with one-step FEM. It is put forward that the final part should consider the
effect of the technology. Through comparing one-step FEM with incremental method, it is showed
that one-step FEM could calculate rapidly and had some credibility. It was suitable to evaluate the
formability at the early stage of product design.
Study on Flow Stress Model of a Microalloyed High Strength Steel in CSP Hot Rolling
Authors: Xu Guang , Wan Lun , Zhang Xin Qiang , Xue Zheng Liang
Published: March 2009

Hot simulation tests at different deformation technology parameters were carried out for a
microalloyed high strength steel produced by CSP hot rolling and the stress-strain curves during
deformation were measured. Based on the experimental results and the discussions of present flow
stress models, a new flow stress model incorporating interactional effect of deformation temperature,
strain and strain rate on flow stress was developed in the paper. Excellent agreement between
measured and predicted flow stress values is obtained for new flow stress model of a microalloyed
high strength steel rolled by CSP. In addition, the comparisons of flow stress prediction errors
between several models and one given in the paper reveal that the prediction accuracy of new flow
stress model presented in the paper is higher than other models.
Simulation of Molding Flow of Sheet Molding Compound in Complicated Dies
Authors: Mei Qi Lin , Yan Shi Lin , Huang Zhi Xiong , Guo Jian Juan
Published: March 2009

Based on generalized Hele-Shaw(GHS) model, numerical simulation of
compression-molding flow of sheet molding compound (SMC) in complicated dies is realized by
control volume/finite element method (CV/FEM). Finite element computing and post analysis
programs have been written. The flow fronts of SMC charge during compression molding are
tracked, and the time needed of mold filling in complicated dies is predicted. The results of
simulation are helpful for the placement of SMC charge, the design of mold and the optimization of
technological parameters.
Finite Element and Experimental Analysis of Three-Dimensional Flow State of Plastic Melt in Slit Die Section
Authors: Qin Sheng Xue , Zhao Guo Qun , Mu Yue , Xu Xing Ming
Published: March 2009

In this paper, penalty finite element method is applied to the simulation of
three-dimensional incompressible viscous steady flow, and the program is coded for analysis of
three-dimensional flow process of plastic melt in extrusion die. Slit die is typical in polymer
extrusion process, and the relevant part is used widely. Because the flow law is different for various
polymers with different rheological character even in the same die, the polymer flow in slit die is
simulated for Newtonian fluid and power-law fluid by the program and ANSYS, respectively. Flow
laws of two kinds of fluid are compared, and the result shows that the non-uniform velocity
distribution in outlet is caused by the non-Newtonian effect of material. The penalty factor is
important for the penalty finite element model, which decides the precision and efficiency to a great
extent. The proper penalty value is decided by some factors, for example, the character of the whole
equations and geometric model. Numerical solution with change of penalty value and viscosity is
analyzed, and the result shows that the penalty value should be suited with viscosity in special range
for penalty finite element model. The experiment has been developed, and the velocity distribution
in outlet of slit die is measured. The result of finite element analysis is consistent with experimental
result basically, and the reason of result divergence of the two ways is analyzed. The results show
that the given model is suited for the polymer extrusion process, and the advice of the selection of
penalty value is instructional for penalty element model.
Shrinkage Optimization of Flat Receptacle Using the Finite Element Method
Authors: Xu Zhen Ying , Wang Yun , Dong Pei Long , Xiao Kai
Published: March 2009

Flat receptacle, which is used in extruding the large aluminum profiles, is in harsh work
conditions. Due to the irregularity of inner hole of flat receptacle, inconsistent resistance of shrinking
fitting affects the inner hole within which nonuniform deformation occurs. If the nonuniformity
exceeds the specified dimension accuracy, tiresome work including mould repairing and structure
optimization has to be done. ANSYS is used to simulate the flat receptacle. It is shown that the
maximum stress appears in the arc area of inner hole. Therefore, we present one new method using the
preloaded layer with changeable shrinkage to replace the preloaded layer with uniform shrinkage.
Considering the processing and assembling factors, we adopt the elliptical outer layer and circular
inner layer as the new structure. Then the optimizations of flat receptacle with uniform and
changeable shrinkage are implemented using the optimizing module, receptively. The optimized
results show the maximum equivalent stress in the corner of inner-hole decreases about 5.47% if
adopting the changeable shrinkage. The numerical simulation results show that the feasibility of
changeable shrinkage and elliptical preloaded layer.
Numerical Simulation of Wire-Rod Hot Continuous Rolling Process with Multi-Field Coupling
Authors: Yang Li Cheng , Hu Jin Xiang , Ning Li Wei , Liu Ying Chun
Published: March 2009

High speed wire-rod rolling is a typical large deformation process which includes
geometry, material and boundary condition non-linearity, thus it belongs to a highly nonlinear
problem. The finite element models of the billet and the rollers in the intermediate rolling region had
been established based on actual sizes by using 3-D thermo-mechanical coupling FEM and advanced
contact analysis technology. The deformation field, stress, strain, temperature field and rolling force
of the billet were calculated and analyzed in the rolling passes precisely. The distribution and change
characteristics of temperature had been discussed especially. The results of the simulation are reliable
and precise, which are useful for practical manufacture and the optimization of process-parameters.
Elasto-Plastic Dynamic Explicit Analysis of Cold Ring Rolling Process
Authors: Zhang Xue Bin , Li Zhi Gang , Liu Yu Qi , Wu Ming Hua
Published: March 2009

A special elasto-plastic dynamic finite element code named RingForm has been developed
to analyze cold ring rolling process. Central difference method was introduced to solve the dynamic
explicit finite element equations. Strain state was estimated by the value of yield function of the last
and the present time step. To reduce the accumulative error caused by elasto-plastic constitutive
relations, the radial return algorithm was employed. In comparison with the experimental results, the
cold ring rolling process of a ring with rectangular section has been simulated to verify the accuracy
and stability of the system solver.
Gate Location Optimization in Injection Molding Based on Empirical Search Method
Authors: Huang Xiao Yan , Li De Qun , Xu Qiang
Published: March 2009

In injection mold, design of gate location is among the most critical factors in
achieving dimensionally accurate parts and high productivity of the molding process, since it
influences the manner in which the plastic flows into the mold cavity. To automatically predict the
optimal gate location of injection molds based on injection-molding simulation, a new and practical
method: empirical search method according to the analysis of common optimization methods has
been presented in this article. In this method, the gate location scope is initiated by the practical
experience of mold designer so that the core for the gate location optimization is construction of
empirical library. In order to build the empirical library, in terms of shape and function characteristic
of injection-molding part, all the parts are classified six kinds: shell, container, plate, structural part,
ornamental part and transparent part, and the corresponding design rules are kept in the empirical
library. In addition, this article combines the empirical search method and numerical simulation
technique, builds the mathematics model for the gate location optimization of plate part in empirical
library and obtains the gate location optimization scheme for this kind of part through one concrete
numerical example. The analysis and verification by adopting the software Moldflow testify the
optimization mathematics model is effective.
Numerical Simulation on Pharmaceutical Powder Compaction
Authors: Han Liang Hao , Elliott James , Best Serena , Cameron Ruth , Bentham A.C. , Mills A. , Amidon G.E. , Hancock B.C.
Published: March 2009

In this paper, we present a modified density-dependent Drucker-Prager Cap (DPC) model
with a nonlinear elasticity law developed to describe the compaction behavior of pharmaceutical
powders. The model is implemented in ABAQUS with a user subroutine. Using microcrystalline
cellulose (MCC) Avicel PH101 as an example, the modified DPC model is calibrated and used for
finite element simulations of uniaxial single-ended compaction in a cylindrical die. To validate the
proposed model, finite element simulation results of powder compaction are compared with
experimental results. It was found that finite element analyses gave a good prediction of both the
loading-unloading curves during powder compaction and the compaction force required for making
a tablet with a specified density. Further, the failure mechanisms of chipping, lamination and
capping during tabletting are investigated by analysing the stress and density distributions of
powders during the three different phases of the tabletting processes, i.e. compression,
decompression and ejection. The results indicate that the model has excellent potential to describe
the compaction process for generic pharmaceutical powders.
Numerical Simulation on Laser Peen Forming of Sheet Metal
Authors: Zhou Jian Zhong , Fan Yu Jie , Huang Shu , Jiang Su Qing , Du Jian Jun
Published: March 2009

In order to understand and control the process of laser peen forming (LPF) of sheet
metal, a developed FEM model was established and the process of LPF was simulated by FEM
code ABAQUS. Special emphasis was posed on the part of the model devoted to the analysis of
3D residual stress distribution under laser shock wave loading. With the aid of simulation method,
the influence of laser parameters, number of shots, peening tracks and the characteristics of sheet
bending were investigated. The results indicate that the bending deformation of metal sheet is
relative to laser peening numbers, peening coverage and the plate’s thickness, both upper and back
layers of the deformed sheet exists residual compressive stresses.
Deformation Pattern of the Large Generator’s Retaining Rings during Hydraulic Bulging Strengthening
Authors: He Wen Wu , Liu Jian Sheng , Guo Hui Guang , Chen Jin Ke
Published: March 2009

In accordance with hydraulic bulging strengthening technology for large generator
retaining rings (Mn18Cr18N), the bulging deformation process of retaining rings is simulated by
MARC software. The key factors such as the punch taper angle and contact pressure are analyzed
which influence on the deformation. It has been proofed for carbon steels with small ratio mould .It
is observed that adjusting the punch taper angle and controlling the contact pressure theoretically
can make the rings deforming uniformly during the hydraulic bulging strengthening processes, and
these results provided the credible theoretical bases of technology application.
Simulation of Internal Stress in Injection Molded Parts
Authors: Wu Hai Hong , Zhao Zhen Feng , Shen Chang Yu
Published: March 2009

The development of internal stress in injection molded parts is analyzed. Different
from other researches, this study uses a new modified Maxwell model to calculate the internal stress.
On the basis of the creep experiments of injection molded parts, a non-linear constitutive equation is
proposed. Non-linear finite element equation to calculate the internal stress is derived. By means of
this model, the internal stress of an injection molded polystyrene plate is simulated. The effects of
mold wall temperature, cooling time and packing pressure on the development of internal stress are
investigated. The predicting results are in good agreement with experimental data.
Investigation on the Simulation System of GTAW Operation Based on Virtual Reality Technology
Authors: Liang Zhen Xin , Zhang Jian Xun , Pei Yi
Published: March 2009

Gas shield Tungsten Arc Welding (GTAW) is an important process method in material
processing. Welding quality is vital for the product quality. It is an important way to improve the
quality of product by raising the personal capability and handling technique of the welder. In this
investigation, because of the deficiency in classic welding training scheme, some new technology
were introduced into classic welding training field to improve the efficiency of welding training and
reduce training cost. A computer simulation system that can be used to train primary welders was
developed combined with three-dimensional stereoscopic vision and API interface of OpenGL,
virtual reality is the kernel technology. In this system, welders were trained not in the real operating
environment but in the virtual environment where has experience personally effect that simulated
by computer. There is unnecessary with welding material and welding energy in virtual
environment simulated by computer. It has highly automatic and intelligent and lower required to
welding teachers. It is healthy to welder because that intensive arc and harmful dust are disappeared
in virtual environment. It is a lower cost and high efficiency method by use of virtual training
system to training new welder.
Evaluation of Corrosion Property for Repair Welding Zone of Exhaust Valve
Authors: Moon Kyung Man , Cho Hwang Rae , Lee Myeong Hoon , Kim Yun Hae
Published: March 2009

The diesel engine in the merchant ship is being operated in severe environment more and
more because temperature of exhaust gas of combustion chamber is getting higher and higher with
increasing of using the heavy oil of low quality as the oil price is significantly being jumped for recent
some years. As a result, the degree of wear and corrosion in between spindle and seat ring of exhaust
valve are more particularly serious compared to the other parts of the engine. Thus the repair weld to
the spindle and the seat ring is a unique method to prolong the life of the exhaust valve in an
economical point of view. In this study, corrosion property of both weld metal and base metal was
investigated with some electrochemical methods in natural sea water solution, in case of being welded
with some welding methods and welding materials to the exhaust valve specimen as the base metal. In
all cases, corrosion resistance of the weld metal was considerably superior to the base metal. In
particular the weld metal of A2F(AC Shielded Metal Arc Welding with two pass by foreign electrode)
showed a relatively good corrosion resistance compared to the other weld metals Furthermore pitting
was somewhat observed at the corroded surface of the base metal while there was no its phenomenon
on the surface of the weld metal.
Numerical Simulation of Pulsed Arc Welding by Melting Electrode
Authors: Shpigunova O.I. , Glazunov A.A.
Published: March 2009

In this paper the processes of melting and transfer of an electrode metal to the molten
pool, hydrodynamics of molten pool in controlled pulsed arc welding in carbon dioxide have been
investigated. The process of pulsed arc welding with systematic short-circuits of the arc gap is
realized by adaptive algorithms of pulsed control over main energetic parameters of welding - arc
current and voltage, arc heated efficiency, peak short-circuiting current, which provide the dosage
of energy for melting and transfer of every drop of an electrode metal, the control over fluidity of
the weld pool. Physical and mathematical models describing such processes in CO2, original
software have been developed. The results of physical simulation and mathematical modelling
permit to determine the influence of energetic parameters of the process on the condition of the
“power source – electrode – arc – molten pool” electrodynamic system at each moment of time.
Numerical Simulation of Hydrostatic Extruding Cu/Al Bimetal Clad through Equal-Strain Contour Concave Die
Authors: Zhang Chao Hui , Liang Yuan , Wang Fu Chi
Published: March 2009

A bimetal composite material is a variant of the typical composite that is composed of
two materials joined at their interface surface. The advantage of clad material is that the
combination of different properties of materials can satisfy both the need of good mechanical
properties and the demand of user such as electrical properties simultaneously. This paper is
concerned with the hydrostatic extrusion process of copper-clad aluminum rod. The commercially
available finite element program ANSYS was used to simulate the process of hydrostatic extrusion
for Cu/Al bimetal composite through the equal-strain contour concave dies. The relative slippage
between the inner and outer metals under the condition of different friction factors is studied, and
the stress-strain distribution in the billet was analyzed. Experiment test was carried out; it was
found that the experimental result has good agreement with relative slippage from the finite element
analysis.
A Study on Numerical Analysis and Residual Stress Evaluation of Welded Joint
Authors: Huh Sun Chul
Published: March 2009

The structures of existing wings had holes for light weight and plates and frames were
fixed with rivets or screws, thus, there were difficulties and limits in light weight. Welding process
generates distortion and residual stress in the welding due to rapid heating and cooling. Welding
distortion and residual in the welded structure result in many troubles such as dimensional
inaccuracies in assembling and safety problem during service. The accurate prediction of welding
residual stress is thus very important to improve the quality of welding and find the way to reduce
itself. In this study, an improvement was made in current joint methods through EB welding and
laser welding for light weight of wings and welding strength was measured through strength test. In
addition, finite element analysis was performed for welding process so as to induce optimum
welding condition.
NiCr Alloy Coating Deposited on the Surface of 35CrMo Steel by the Electrospark Process
Authors: Yu Hua , Shi Hong Xin , Wang Yao Li , Zhang Ke Ke , Wang Wen Yan , Han Li Juan , Pang Qing Hua
Published: March 2009

Strengthened coating on the surface of 35CrMo steel alloy was deposited by
electrospark process using NiCr electrode. The bond strength and microhardness of the coating was
checked and the microstructure of the strengthened coating was analyzed using the optical
micro-scope, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion
spectrum (EDS). The results show that the bond strength between the coating and the base metal is
495.1MPa, and the hardness of the coating surface is about 2 times than that of the base metal, and
the property of the workpieces surface has become better. The coating is a metallurgical reacting
bonding layer between the base metal and the NiCr electrode, and its main ingredients are FeNi and
NiCrFe.
Study on Deformation Induced Ferrite Transformation in Mild Steels with or without Niobium
Authors: Wang Li Jun , Yao L.D. , Ren H.P. , Liu Chun Ming
Published: March 2009

Two mild steels with Nb-microalloying and Nb-free were smelted. After single-pass hot
compression of various processes conducted on a Gleeble-2000 thermomechanical simulator, the
effects of deformation conditions and Nb-microalloying on microstructural evolution kinetics,
including the volume fraction, grain size and grain number per unit area were investigated through
quantitative metallographic analysis. The experimental results show that, grain number per unit area
of DIF increases with decreasing deformation temperature or increasing deformation amount; the
grain size of DIF is not very sensitive to the deformation conditions; the volume fraction of DIF
increases due to the increased grain number per unit area. The microalloying element of Nb
dissolved in austenite inhibits the grain growth and reduces the volume fraction of DIF.
Numerical Modeling of the Electrical Resistivity of Carbon Black Filled Rubber
Authors: Xie Zhi Min , Yum Young Jin , Min Han Gi , Son Jin Hyug
Published: March 2009

Carbon black (CB) filled rubber is microscopically heterogeneous although homogeneous
on a macroscopic scale. CB particles are generally in the form of aggregates, which form the CB
network in the rubber matrix. In this work, the junction width between CB aggregates is modeled as a
contact resistor and the tunneling conduction mechanism is taken into account, and then an infinite
circuit consisting of numerous contact resistors, interconnected with each other, is proposed to
simulate the CB network in filled rubber. Prior to determination of the junction width distribution, CB
spheres equivalent to CB aggregates in volume is assumed in a specifically random arrangement.
Thus, the effect of CB aggregate distribution on the electrical resistivity is discussed. It is found that,
for CB (N330) filled natural rubber with volume fraction of 27.5%, the simulated electrical resistivity
at a standard deviation of 0.1 mean junction width is in good agreement with the experimental data
available in the literature.
A Numerical Study on Nonequilibrium Heat Transfer and Crater Formation in Thin Metal Films Irradiated by Femtosecond Pulse Laser
Authors: Sim H.S. , Kang K.G. , Lee Seong Hyuk , Kim Jong Min , Shin Young Eui
Published: March 2009

The ultimate goals of this study are to investigate numerically nonequilibrium energy
transfer between electrons and phonons, and to predict the crater formation shapes of gold thin film
structures irradiated by femtosecond pulse lasers. In particular, the present article expands the onedimensional
two-temperature model (1DTTM) to the two-dimensional model (2DTTM) considering
wave interference, and it involves the quantum effect to predict thermal and optical properties. The
predictions by using 2DTTM are extensively compared with those of 1DTTM, and the influence of
film thickness on radiation heat transfer and optical characteristics are also examined. From the
results, it is found that the predictions of 2DTTM are in good agreement with those of 1DTTM. As
the gold film thickness decreases, the reflectivity decreases dramatically and the absorbed laser
intensities at the top surface increases substantially because of wave interference in thin films.
Reliability Evaluation of QFP Solder Joint Using Sn-8Zn-3Bi Solder Paste during the Thermal Shock Test
Authors: Han S.W. , Chang Kyong Ho , Han J.G. , Cho Il Je , Kim Jong Min , Choi M.G. , Kim Y.T. , Shin Young Eui
Published: March 2009

The reliability of QFP (Quad flat package) solder joint using Sn-8Zn-3Bi solder paste
under the thermal shock test was investigated. Considering the environmental restriction such as
ROHS, the QFP Cu LF (Lead-frame) was coated with lead-free materials (Sn, Sn-3Bi). To analyze
the reliability under thermal shock treatment, the samples were placed in the thermal shock chamber
(248K/423K, Dwell time: 30min). During the thermal shock test, the solder joint cross-sections
were observed every 500 cycles. No crack initiation and propagation was observed through all type
of plated Cu LF. The measured pull strength slightly decreased, as the number of cycles increased.
After 1000 cycles, the pull strength of Sn and SnBi plated Cu LF reduced by 30% and 20%,
respectively, compared with that of initial condition. Observing the fracture surface morphology by
FE-SEM, the fracture mode changed and the IMC fractured area on the both fracture surface was
increased. The IMC was identified as γ-Cu5Zn8 by chemical composition analysis using EDS. The
reduced pull strength was affected by IMC fracture and fracture mode change. However, the pull
strength does not decrease steeply but gradually. Consequently, the Sn-8Zn-3Bi solder joint shows
the reliable solder joint strength, fracture mechanism, and compatibility with lead-free plated Cu LF
during the thermal shock temperature of 248K to 423K.
Comprehensive Analysis for Microstructure Evolution in Welding
Authors: Terasaki Hidenori , Komizo Yuichi , Yonemura Mitsuharu , Osuki Takahiro
Published: March 2009

Unidirectional solidification for low-carbon steel weld metal was characterized by using
Time-Resolved X-Ray Diffraction (TRXRD) system. Solid-state phase transformation was also insitu
observed in reciprocal lattice space. It was shown that TRXRD analysis had a potential as a
comprehensive characterization technique for solidification and phase transformation process in
welding. It made for the growth behavior of dendrites in unidirectional solidification and α γ δ − −
phase transformation in steel weld metal to be characterized.
Finite Element Modeling of Laser Spot Welded Lap Joint
Authors: Gao Zhi Guo , Huang Jian , Wu Yi Xiong
Published: March 2009

For many years, rivet joint technology has been applied in the automotive and aerospace
industry. Recently, it began to apply laser welding technology to lap joints instead of rivet joining.
Laser spot welding has some potential advantages including time saving, cost reduction, material
saving and weight reducing. A lap joint of aluminum alloy LY12 with different plate thickness,
namely 2mm and 1mm, was spot-welded by CO2 laser. For the welding, laser power in pulse form
with ramping-up and cooling-down shape was used, and pure helium gas served as shielding gas to
fill around welding area. In this study transient three-dimensional non-linear finite element
modeling was used to analyze heat flow and residual stress of the laser spot welding of aluminum
alloy LY12. In modeling the temperature dependence of material properties, influence of contact
surfaces are taken into account. To analyze, Gaussian distributed heat source model and
thermo-elasto-plastic behavior were applied. Weld dimensions and residual stress at the weld
surface were calculated numerically and compared with the experimental results.
Spatter Reduction of Steel Sheets Welding Using Controlled Bridge Transfer (CBT) GMA Process
Authors: Era Tetsuo , Ide Akihiro , Uezono Toshiro , Ueyama Tomoyuki
Published: March 2009

In non-pulsed GMA welding, spatter can be reduced by controlling the short-circuit
current to a low level just before the re-arcing. The reduction of spatter requires improving the
accuracy of predicting the re-arcing by stabilizing the molten metal transfer, and improving the
consistency of accuracy against disturbances. The Controlled Bridge Transfer (CBT) process, which
optimizes the accuracy of predicting the re-arcing in real time in response to the molten metal
transfer, realizes stable, low spatter level GMA welding.