bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of the Deformation Behavior of ABS Resin at Elevated Temperature and High Strain Rate
Authors: Yin Z.N. , Ma X.S. , Wang Tie Jun
Published: March 2009

Split Hopkinson Pressure Bar (SHPB) experiments are carried out to study the deformation
behavior of acrylonitrile-butadiene-styrene (ABS) resin at elevated temperature and high strain rate.
The temperature and strain rate considered are 293K and 343K and 8.0×102s-1, 2.7×103s-1 and
1.0×104s-1, respectively. The curves of engineering stress and strain at different temperatures and
different strain rates are experimentally obtained. The effects of temperature, strain rate and the
fraction of ABS on the deformation behavior of ABS resin are discussed in detail. Then, a rate and
temperature dependent phenomenological constitutive law for ABS resin is developed.
Vibration Characteristic Prediction of a Heavy Machinery Suspension Seat Using Multi-Body Dynamic Analysis Method
Authors: Lee W.C. , Kim Chae Sil , Choi H.O. , Jung Y.G. , Song Jung I.
Published: March 2009

This article proposes a novel simulation technique to predict the reasonable dynamic
characteristics of a suspension seat for heavy machinery using a commercial multibody dynamic
analysis code, ADAMS. The dynamic model is simulated with the specific condition such as
sinusoidal and sweep input. The experiment test for actual suspension seat is conducted for
reviewing the dynamic simulation model with same input condition. As the simulation results shows
good agreements with experimental test results, the dynamic analysis model is reasonable and will
be very helpful for predicting the dynamic characteristic for the suspension seat for heavy
machinery and for designing the other type seats with the other suspension mechanism types.
Non-Destructive Inspection of Rebar Corrosion in Concrete Structures by Using BEM and GA
Authors: Minagawa Koichi , Hayabusa Keisuke , Ridha M. , Amaya Kenji , Aoki Shigeru
Published: March 2009

An inverse problem is analyzed where corrosion of rebars is detected from a small number
of potential data measured at the surface of concrete structure. Because the shape and number of
corrosion in rebars are not known in advance, usual inverse analysis method in which the shape and
number of corroded part are assumed is not available. In this research, the genetic algorithm (GA) is
employed without any assumption. The fitness in the multi-step GA is defined as the inverse of
difference between experimental and numerical potential values, and is evaluated by the boundary
element method (BEM). To reduce the computational time, the net elements, which have been
recently developed by the authors for corrosion analysis of net structures, is used together with the
multi-step GA. It is shown by a simulation that the multi-step GA with net elements are successfully
employed in the inverse analysis.
Effect of Hot Bar Shape on Temperature Consistency
Authors: Lin Meng Ju , Lee Jen Cheh , Hwan Chung Li , Liao Jung Nan
Published: March 2009

Pulse heated reflow soldering is widely used as junction methods of electronic devices such
as ACF, HSC, FPC, PCB, TCP, and FFC. Hot bars are the devices used in pulsed heated reflow
method to heat and melt the solder materials between devices and wire becoming a junction.
Therefore the performance is determined by the welding properties. The welding time, temperature
and induced pressure are important factors affecting welding property. And the temperature has the
significant effect due to electricity and mechanical property of solder being determined by welding
temperature. However, the consistency of temperature is hard to achieve due to complex coupling of
driving current, materials property, heat generation, heat conduction and hot bar shape. In this work,
different shapes of hot bat are designed to obtain the temperature consistency. Due to the welding
requirement, the heating process is a two steps process. And the hot bar is heated by electric current
from power supply with feedback control. For assembly purpose, the hot bar is designed as a
rectangular plate with circular holes near the other side respect to the heating edge to fasten the hot bar
on the welding machine. And the hot bar with polygon hole in the center part would induce the
uniform temperature distribution. Four dimensions of the hot bar determine the shape and investigate
the temperature consistency: polygon’s sizes and its positions. Some experiments are made to
measure the temperature distribution. The results show the shape has significant effect on temperature
consistency. Changing the polygon hole positions will alter the temperature distribution. The central
part of heating edge will hotter than both ending part initially. And in some cases, during the heating
process, the both ending part will have cooler, hotter, and cooler temperature that central part with
respect to heating time. The polygon hole sizes have also significant effect on the temperature
distribution. They have the similar temperature distribution phenomena as positions effect. Therefore,
from the experiments and analysis, the hot bar could have more uniform temperature distribution by
shape design. And it is also found the temperature distribution would induce thermal residual stress
and deform the hot bar.
Phenomenological Mechanism of Transformation Plasticity and the Constitutive Law Coupled with Thermo-Mechanical Plasticity
Authors: Inoue Tatsuo
Published: March 2009

Phenomenological mechanism of transformation plasticity is proposed in the first part of
the paper by use of simple model why stress in mother phase increases to reach yielding due to
progressing new phase and to induce plastic deformation even under small applied stress. Based on
the discussion, a unified constitutive model including transformation-induced and ordinal thermomechanical
plastic strain rates by introducing an effect of varying phases during phase transformation
into yield function. Thus derived constitutive equation is applied to describe strain response under
varying temperature and stress with some discussions as well as metallo-thermo-mechanical
simulation of quenching.
FEM Analysis and Optimization for Welded Metal Bellows Seal
Authors: Nuer Rabiya , Gheni Mamtimin , Ahmat Mutellip , Jia Li Hua
Published: March 2009

This study has set up 3D model of Welded Metal Bellows Diaphragms with the Geometry
module of MSC.Patran software, turn into the finite element and analyse models in MSC.Patran
software , has carried on finite element analysis with MSC.Nastran under the loaded operating mode
condition that is giving definitely, have received stress distributing and deformation situation of
Diaphragms, has carried on optimization design to Diaphragms on this basis.
Stress Classification and Fatigue Life Assessment of Modular Component with Asymmetric Perforated Parts
Authors: Chang Yoon Suk , Choi Shin Beom , Park Young Jae , Choi Jae Boong , Kim Young Jin , Lee Jin Ho , Chung Hae Dong , Seul Kwang Won
Published: March 2009

In the ASME Code Section III ‘design by analysis’ approach, stresses are determined by
numerical method and compared with corresponding stress limits. This approach provides several
stress criteria for fatigue life assessment and procedures for categorizing the representative stress
components. Since the stress criteria were derived from two-dimensional basis, however, it may
inappropriate to delineate structural components with complex geometry. In this paper, detailed
transient analyses are performed for modular pressurizer with an asymmetric geometry, which
includes perforated parts to mount various piping and equipments. Also, the applicability of an
effective elastic modulus to consider the perforation and the appropriateness of stress linearization
method using stress classification line are assessed. Then, the cumulative usage factor as well as stress
intensities at critical locations of the pressurizer are calculated and compared with corresponding
allowable design stress limits. The key findings of this work can be used to make regulatory guides for
evaluation and confirmation of structural intensity of components with asymmetric perforated parts.
In Situ Observation of Fatigue Crack Growth and 90º Domain Switching for BaTiO3 Ferroelectric Single Crystal under Cyclic Electric Loading
Authors: Fang Fei , Zhang Fang Cheng , Yang Wei
Published: March 2009

In-situ observation of the fatigue crack growth and 90o domain switching was carried out
for BaTiO3 ferroelectric single crystals under alternating electric field. It is shown that during the
electric cycling, the crack propagates continuously. Parallel lines of 90o domain boundaries can be
seen and they flip at each reversal of the alternating electric field. The width of the 90o domain
switching zone grows with the number of cycles and its frontal always lies ahead of the crack tip. It is
suggested that the cyclic stress field induced by the repeated 90o domain switching at the crack tip, as
well as the stress field caused by the electrically activated material between the electrode and the
material under the electrodes contribute to the observed fatigue crack growth.
Research of Centroid Balance of the Inspection Robot for High-Voltage Transmission Lines
Authors: Jin Jian , Zhang Ting Yu , Zhang Guo Xian
Published: March 2009

According to the requirements of the power department, a new type of inspection robot that
works along ground wires is developed in this paper. The robot can navigate counterweights, clamps
and particular the towers autonomously. The locomotion principle of tower-navigation is presented.
In order to decrease the mass eccentricity of the robot, a centroid balance method is proposed. Virtual
prototyping technical is used to validate the centroid balance method. It proved that the proper
movement of the electric box can adjust the robot centroid distribution efficiently. Driven torque and
the power cost of the whole system both decrease a lot. And the robot works more safely.
An E-Learning System for CAE
Authors: Kawai Hiroshi , Kuwata Akira , Noguchi Hirohisa
Published: March 2009

An e-learning system for computer-aided engineering is developed. The system is
designed as a Web-based rich client (or rich Internet application, RIA), so that anybody can learn
CAE skills from anywhere, anytime. Mesh generation, finite element analysis and visualization
capabilities for a set of benchmark problems, such as cantilever beam and plate with hole, are
implemented using FLASH ActionScript language. It is combined with a CAE educational program,
dedicated for under-graduate students and novice engineers in mechanical and architectural
industries.
Web Based CAE System and Knowledge Sharing Framework Using Web 2.0 Technologies
Authors: Wada Yoshitaka
Published: March 2009

There are several studies for developing web-based CAE applications to substitute existing
CAE applications. CASOW is the web-based CAE system developed by the author. The approach for
implementation of the system is to use fundamental technologies, for instance, HTML, HTTP, CSS
and so on, because we cannot know whether new technologies will be alive or not. Certain
technologies bring specific advantages to the applications, but a life time of the application would be
short. Recently a great advantage of web interface is developed. Such a representative application is
Google Maps which doesn’t require any special software components; however the application
realizes interactiveness of the application. The technology is called Ajax which drastically overcomes
the bad interactiveness on the web browser. On the other hand, high efficiency of analysis work with
high performance computers produces many kinds of knowledge and a large amount of information.
We are confronted with inefficient knowledge and information management in the network system.
This paper presents the new web-based CAE system using Ajax and knowledge sharing framework
with compatibility to web interface. The system is presented, and advantages of the interface,
effectiveness of the API in the system and knowledge sharing framework are discussed.
Fatigue Life of Thread Connection for Casing Drilling under Tension and Torsion
Authors: Wang Feng Hui , Wu Qiong , Wu Ying Xi , Song Sheng Yin
Published: March 2009

Casing drilling technique which has been dramatically developing is a revolution in
petroleum industry and has aroused great concerns. The fatigue failure of casing thread connection is
a critical issue for using. Therefore, to study the fatigue failure of casing connection is an important
issue for understand the life of casing drilling. For the notched element, how to estimate the life and
which parameter (equivalent stress, equivalent strain ,or the strain in the root )represent the damage
under fatigue condition is still a problem. The purpose of this paper is to investigate the fatigue life of
notch element under multiaxial stresses and to find out the damage parameter so as to predict the life
of notch element. First specimen were machined with the same notch geometer dimension as the
casing thread connection, fatigue tests with tension and torsion loading were carried out by fatigue
test machine , for stress levels designed to obtain S-N lifetime curve. The stress and strain for the
connections subjected to proportional loading were analyzed by elastic-plastic finite element method.
The stress-strain state for notched specimens subjected to constant amplitude proportional multiaxial
loadings was also calculated and analyzed by the finite element model. Take the equivalent stress,
equivalent strain and the strain by FEM in the root into the prediction model, the strain by FEM has a
good agreement with the experiment.But the results from the equivalent stress and equivalent strain
also in good agreement with the experiment and is thought to be a simple prediction way.
Fracture Analysis for Damaged Aircraft Fuselage Using Substructure Method
Authors: Ju Jin San , You Xiao Chuan , Jiang Xiu Gen , Zhuang Jin Zhao
Published: March 2009

This paper primarily describes the development and application of substructure
computational analysis techniques to determine stress intensity factors for the damaged panels
subjected to fatigue internal pressure. A program based on substructure analysis technique has been
developed for the fracture analysis of curved aircraft panels containing cracks. This program may
create whole model which consists of substructure superelements and obtain fracture parameter of the
crack by expanding results in superelement automatically. For instance, a typical test curved panel
model consists of 7 frames and 8 stringers is calculated. This numerical approach has been validated
through comparison between the calculation SIF results and available experimental data of a typical
test panel with a longitudinal crack. The technique that has been established here is also applied to the
other analysis of a test series of cracked panel with 7 frames and 10 stringers. SIFs of four cracks in it
with different crack lengths are obtained efficiently.
A Study of Creep Properties of Polymer Bonded Explosives
Authors: Liu Zhan Wei , Xie Hui Min , Chen Peng Wan , Huang Feng Lei
Published: March 2009

Creep properties of polymer bonded explosives (PBXs), a particulate composite, was
studied by using the method of moiré interferometry in this paper. The specimens fabricated by
different heat pressing technology were used. Extensive creep deformation of PBXs material was
indirectly measured by the aid of compressive circular disk test. The obtained results shown that creep
properties are greatly influenced by pressing pressures and temperature of heat pressing technology.
The results indicated that the higher the temperature and the pressing pressure are in the heat pressing
technology to some degree, the better the PBXs material creep resistance is. The creep fracture
surfaces of PBXs were also observed using Scanning Electronic Microscopy (SEM). It was shown
that most of the fracture crack was initiated and propagated along the explosives crystal surface
during creep.
Analysis of Finite Element Viscoelastic Displacement Based on Kelvin Model
Authors: Liu Ning , Zhu Wei Shen , Li Xiao Jing
Published: March 2009

Considering the time effect of surrounding rock and the long time stability of the
underground caverns after being excavated, a method on the finite element viscoelastic displacement
based on Kelvin model. The recursion formula is obtained by the displacement analytic solution of
Kelvin model. It can be used to predict the viscoelastic displacement development fast and
accurately. Finally this method is employed into a project, and the calculated values by this method
agree well with the measured values. Prove that the method is effective.
Influences of RE-Ti Composite Modification on the Structure and Properties of W6Mo5Cr4V2 Alloy
Authors: Feng Xi Lan , Jiang Zhi Qiang , Hu Zhong Yan
Published: March 2009

The structural change and properties of W6Mo5Cr4V2 alloy (M2 steel) inoculated by
addition of rare earth (RE)-Ti were investigated. The results indicated that the impact toughness and
fracture toughness were increased distinctly due to network eutectic carbides elimination, matrix
structure refinement, and well-distribution of eutectic carbides. The hardness of modified M2 steel
hardly changed. In addition, the high temperature wear resistance was improved.
Analysis of Interfacial Debonding of RC Beams Strengthened with CFL
Authors: Deng Jiang Dong , Huang Pei Yan , Guo Xin Yan , Deng Jun
Published: March 2009

The interfacial bonding property between carbon fiber laminate (CFL) and concrete is a
key issue in the application of RC beams strengthened with CFL. In this paper, fracture mechanics
method is used to develop a calculation formula of stress intensity factor for the CFL-concrete
interfacial crack. In combination with a series of tests, the interfacial fracture toughness is discussed,
and the influencing factors and process of the intermediate crack-induced debonding (IC debonding)
are also analyzed. The tests results show that IC debonding is generally induced by the flexural or
flexural-shear cracks in the bottom of RC beams around the mid-span, and develop along the
interface towards the end of the beam. A method to determine IC debonding derived from theoretic
analysis and the tests results demonstrates that the interfacial failure can be effectively avoided by
limiting CFL strain in the range of the debonding strain.
Experimental and Analytical Study on the Mechanical Behavior of Stitched Sandwich Composite Panel with a Foam Core
Authors: Zheng Xi Tao , Zhang Jian Feng , Yang Fan , Chai Ya Nan , Li Ye
Published: March 2009

To quantify the effect of structural through-thickness reinforcement in foam core sandwich
composite panels, an experimental study was carried out which included three-point bending tests,
core shear tests, flatwise tensile and compression tests, as well as edgewise compression tests.
Standard test procedures based on ASTM guidelines are followed to test the behavior of the stitched
panels with reinforcement at 90 degree orientation with respect to the sandwich faces. The test
specimens were manufactured by using polyurethane foam Rohacell 71 IG and carbon fiber
reinforced composite facesheets. The dry perform facesheets and foam core were then assembled in a
dry lay-up already stitched. Kevlar 29 yarn was used to stitch both sets of panels. The results showed
a significant effect of the stitching on the in-plane Young’s modulus which was attributed to local
displacements of the in-plane fibers and changes in the fiber volume fraction. Stitching of sandwich
panels significantly increases the maximum failure loads under flexure, core shear, flatwise tensile,
flatwise compression, and edgewise compression loading.
A finite element based unit-cell model was developed to estimate the elastic constants of
structurally stitched foam core sandwich composite panels taking into consideration the yarn
diameter, the stitching pattern and direction as well as the load direction. Depending on these
parameters, local changes of the fiber volume fraction as well as regions with undisturbed and
disturbed fiber orientations within the laminate plies are taken into account. A good match between
the finite element modeling and the experimental data was obtained. The present work should be
considered as a step towards developing a more sophisticated numerical model capable of
describing mechanical behavior of sandwich structures.
Subsurface Deformation of Worn Al-Cu and Al-Mg Alloys
Authors: Ghazali Mariyam Jameelah , Rainforth Mark W. , Abdullah Shahrum , Ihsan A.K.A. , Hassan M.
Published: March 2009

This paper investigates the subsurface deformation of two types of aluminium alloys with
differing nature; A2124 (precipitation-hardened) and A5056 (work-hardened), sliding against an M2
tool steel slider. With block-on-ring configuration, the wear test was carried out at different loads
ranging from 23 - 140N, in a dry sliding condition. Detailed secondary electron microscopy (SEM)
performed on the longitudinal cross sections of the worn alloys indicates that the subsurface deformed
layer beneath the worn surfaces is composed of a number of distinct layers like the mechanically
mixed layer (MML), the shear deformed and bulk layers with increased hardness as the surface was
approached. Deformation below the MML followed the expected behaviour of an exponential decay
of strain with depth. In contrast to other studies in the literature, a linear relationship between depth of
deformation and specific wear rate was not found for both alloys. This was believed to a result of the
MML, which occupied a great proportion of the total depth of deformation. The relationship between
the characteristics of the MMLs especially on the work hardening as a function of alloy type is also
discussed.
Nonlinear Bending of Composite Circular Plates with Embedded Shape Memory Alloy Fibers
Authors: Li Shi Rong , Yu Wen Shan
Published: March 2009

Based on Brinson’s one-dimensional thermo-mechanical constitutive relations of shape
memory alloys and the theory of thin plates in the von Kármán sense, the response of bending of a
uniform heated circular plate embedded with SMA fibers in the radial directions and subjected to a
uniform distributed mechanical load is studied. The characteristic curves of the central deflection
versus temperature rise of the circular plate with both clamped and simply supported boundary
conditions are obtained. The numerical results show that, the recovery forces of the pre-strained SMA
caused by the phase transformation from martensite to austenite can modify the bending deformation
significantly. So, it can be concluded that the bending deformation can be adjusted effectively and
actively by embedment of the SMA fibers into the circular plates
Characterization of Expanded Graphite/Flake-Type Graphite Filled Conductive Polymer Composites
Authors: Oh Kyung Seok , Heo S.I. , Yun J.C. , Han Kyung Seop
Published: March 2009

Conductive polymer composites (CPCs) consisting of expanded graphite (EG), flake-type
graphite (FG) and thermalsetting resin were fabricated by means of a preform molding technique.
Conductive fillers, EG and FG, were mechanically mixed with the phenol resin to provide an
electrical property to composites. The filler loadings were fixed at 75wt.% to obtain a high electrical
conductivity. The mechanical and electrical properties of CPCs were optimized according to the
weight ratio and the particle size of FG. As the weight ratio increased, the flexural strength increased,
however, the electrical conductivity decreased for both cases of CPCs using different sizes of FG. The
particle size was an important parameter to change the mechanical and electrical behaviors. The
flexural strength was sensitive to the particle size due to the different level of densification. The
electrical conductivity also showed size-dependent behavior because of the different contribution to
the conductive networking.
Analytical Solution for the Large Deflection of Fully Clamped Metallic Foam Sandwich Beam
Authors: Qin Qing Hua , Wang Tie Jun
Published: March 2009

A unified yield criterion is proposed in this paper, which is valid for the metallic
sandwich sections with various core strength and geometrical dimensions and can reduce to the
classical yield criteria for solid monolithic section and sandwich section with weak core,
respectively. Then, the unified yield criterion is used to derive the analytical solution for the large
deflection of fully clamped metallic sandwich beam subject to a transversely concentrated load, in
which the interaction of bending and stretching is considered. Comparisons of the present solutions
with experimental results are carried out and good agreements are found. It is seen that the axial
stretching induced by large deflection has a significant effect on the deflection of sandwich
structure in the post-yield regime, and the load carrying capacity of metallic foam core sandwich
beam may be underestimated as the core strength is neglected in analysis.
3D Numerical Simulation of the Deformation of Glassy Polymer
Authors: Jin Ying Jun , Wang Tie Jun
Published: March 2009

The objective of the work is to numerically study the meso-scale deformation of
amorphous glassy polymer. A molecular polymerization algorithm is employed to generate
three-dimensional (3D) random networks of polymer, in which the micro-parameters and
meso-structures, such as entanglement point, sliding point, etc. are considered. Then, 3D unit cell
model and finite element method are used to calculate the stress and deformation relations of
polymer. The evolution of meso-structure of glassy polymer with deformation is obtained
simultaneously. Further, variation of the orientation of polymer chain with deformation was
quantitatively studied.
Jet Projectiles Penetration into Multilayer Metal Targets with Large Interval
Authors: Cheng Wang , Ma Tian Bao , Ning Jian Guo
Published: March 2009

At long standoff, a shaped charge with small cone angle will produce a jet with a high tip
velocity and a low tail velocity, causing it to stretch and break up, so its penetration ability into
multilayer metal targets is very weak, while the penetration depth of explosively formed projectiles is
too low to penetrate into multilayer metal targets. On account of this, the large cone angle shaped
charge, whose internal cone angle is about 100 degree, is proposed and designed in the paper. The
sensitivity of penetration effect into targets to the cone angle of the liner is investigated by experiment.
The results reveal that the shaped charge penetration into multilayer metal targets with large interval
is more optimistic than that of the shaped charge with small cone angle and explosively formed
projectiles. In numerical simulation, based on interface tracking algorithm known as markers on cell
line to reconstruct material interfaces, jet penetration into metal targets is simulated in a
two-dimensional multi-material Eulerian code. The numerical results are in good agreement with the
experimental ones and also indicate the interface tracking algorithm has much better resolution for
moving interfaces, especially effective for large deformation.
Model Testing and Analysis Study on Shear Strength of Rock Mass Containing Multiple Cracks under Compression-Shearing Loading
Authors: Zhu Wei Shen , Sui Bin , Wang Wen Tao , Li Shu Cai
Published: March 2009

Two-phase modelling testing was performed to study the shear strength of rock bridges of
jointed rock mass in this paper. The failure process of rock sample containing multiple collinear
cracks was observed. Based on theory of fracture mechanics and analytical method, a rock-bridge
failure model was proposed and the expression of shear strength was derived. Comparison of
calculated shear strength and the model test results was made and they agree well.
Concrete Durability Test Due to Environmental Degradation Using Environment Simulation Technology
Authors: Li Yun Feng , Lu Yu Hua
Published: March 2009

Using environment simulation technology, simulation testing for environmental behavior
of concrete structure could be developed. Concrete durability experiment and its relative theory
research would be progressed, and it play an important role in ensuring security and durability of
structures. Tailoring environment tests are discussed in the paper, as well as determining all kinds of
environmental factors of durability experiment and constructing several coupling environment.
Simulation tests for environmental behavior of concrete structure will be developed based on the
study.
Fracture Mechanics Analysis on Smart-Cut® Technology: Effects of Stiffening Wafer and Defect Interaction
Authors: Gu Bin , Liu Hong Yuan , Mai Yiu Wing , Feng Xi Qiao , Yu Shou Wen
Published: March 2009

In the present paper, continuum fracture mechanics is used to analyze the Smart-Cut
process, a recently established ion cut technology which enables highly efficient fabrication of
various silicon-on-insulator (SOI) wafers of very high uniformity in thickness. Using integral
transform and Cauchy singular integral equation methods, the mode-I and mode-II stress intensity
factors, energy release rate and crack opening displacements are derived in order to examine several
important fracture mechanisms involved in the Smart-Cut process. The effects of defect interaction
and stiffening wafer on defect growth are investigated. The numerical results indicate that a
stiffener/handle wafer can effectively prevent the donor wafer from blistering and exfoliation, but it
slows down the defect growth by decreasing the magnitudes of SIFs. Defect interaction also plays
an important role in the splitting process of SOI wafers, but its contribution depends strongly on the
size, interval and internal pressure of defects. Finally, an analytical formula is derived to estimate
the implantation dose required for splitting a SOI wafer.
Effect of Cooling Rate on Strength and Fracture Surfaces of Alpha Brass Casting
Authors: Haque Mohammad M. , Ismail Ahmad Faris
Published: March 2009

Green sand casting and chill mould casting methods are representing the slow and fast
cooling rates of the brass casting, respectively. The compositions of the raw material for this study
were about Cu70 and Zn30, which falls under alpha (α) brass. Slow cooling rate casting shows coarse
dendritric structures with large spacing between the dendrites. On the other hand, faster cooling rate
casting shows finer grains with shorter dendrite spacing. The developed structure during solidification
influences the properties of the cast samples. As grain size decreases, the strength of the cast brass
increases; micro-porosity in the casting decreases and the tendency for the casting to fracture also
decreases. However, the macro-examinations of fracture surfaces of these castings show the
differences in the cast samples. Fracture surfaces of the sand cast specimen show larger dimples
taking longer time to break indicating higher elongation. However, chill cast specimen shows smaller
dimples and cleavage type fracture surface having higher strength and lower elongation.
The Crack-Tip Higher Order Asymptotic Fields for a Mode III Crack in a Functionally Gradient Material
Authors: Dai Yao , Yan Xiu Fa , Sun Chang Qing , Tan Wei
Published: March 2009

Crack-tip higher order stress and displacement fields for a mode III crack along the
direction of property variation in a functionally gradient material (FGM), which has a power
variation of shear modulus along the gradient direction, are obtained through the asymptotic
analysis. The asymptotic expansions of crack tip stress fields are derived to explicitly bring out the
influence of non-homogeneity on the structure of the stress field. The analysis reveals that only the
higher order terms in the expansion are influenced by the material non-homogeneity. Moreover, it
can be seen from expressions of higher order stress fields that at least three terms must be
considered in the case of FGMs in order to explicitly and theoretically account for non-homogeneity
effects on crack tip stress fields.
Mesh Generation of Revealable and Non-Revealable Multi-Shaped Sub-Domains
Authors: Gheni Mamtimin , Yin Dong Cheng , Wang Xu Fei , Kikuchi Masanori
Published: March 2009

In this paper, the mathematical model for nonlinear multi-shaped randomly distributed
domains in revealable and non-revealbale fields is established by using waveform mesh generation
(WMG) method with damp, and made the application function of finite element pre and post
handling system. The results show, this method can conduct mesh transformation to any given
nonlinear function or given shapes in different scale randomly distributed domain in revealable and
non-revealable fields, and obtained some smoothly mesh with matching each boundary and
neighboring domains interaction.
Nonlinear Numerical Analysis and Shear Resistance of Timber Column and Beam--Adobe Composite Wall with Finite Element Method
Authors: Tuohuti Akenjiang , Qi Guo Qing , Wang Dun
Published: March 2009

Three different kinds of abode wall and composite abode wall in thickness are calculated
with elastic-plastic FEM. Lateral resistance capacities, crack shapes as well as ductility of abode
wall,of composite wall are analyzed. Based on them, simplified formula is put forward for
calculating the lateral resistance capacities of composites abode wall, which provides a basis for the
design of composite abode wall. In addition, seismic effects of composites abode wall under
different earthquake levels,i.e:frequent intensity, basic and rare intensity are estimated. It indicates
that traditional abode wall with timber columns and beams can satisfy the criterion of rare
earthquake for seismic zone 9. It also shows that the research can be used as the provision for the
transformation and seismic reinforcement of traditional residential buildings in Xinjiang.
Numerical Simulation of RSA Seepage Based on Random Structure Model
Authors: Sun Ji Chao , Wang Guang Qian , Gao Quan Chen
Published: March 2009

The research about seepage of RSA is little, but the material is familiar. There are many
difficulties in laboratory research about the materials, so numerical simulation research in the paper is
introduced. The model of the random structure about SRA is set up, and then the study of seepage is
given. The conversion of the two boundaries is solved correctly in the computer program. So some
conclusions are drawn that the rock blocks the seepage to some degree, and the changing of RSA
seepage is little under the effect of the fluctuating of rainfall intensity, namely the changing of the
seepage is less than the fluctuating of rainfall intensity. The study is the foundation of the next study
about the coupled of stress and seepage of RSA.
Investigation on Characteristics of Structure and Simulation Analysis for Dragonfly Wing Vein
Authors: Li Ying , Wang Xi Shu
Published: March 2009

In this work, the microstructure of the dragonfly wing vein was investigated by the
finite element method (FEM). It is a bionic view to simulate the microstructure of the wing vein,
which could be used to construct the micro air vehicles (MAVs). From the FEM results, the sandwich
structure of the dragonfly wing vein was proved, which could supply more torsional deformation and
reduce the weight of dragonfly. And the protein layer in the sandwich structure almost not bear the
bending loadings, which could protect the protein not to be destroyed. It could assist us to utilize such
design for the new micro air vehicle (MAV), especially ornithopter.
Computer Simulation of the Formation of γ-Precipitates in Nickel-Based Superalloys
Authors: Takahashi Akiyuki , Kawanabe Mitsuru , Kikuchi Masanori
Published: March 2009

Recent 3-Dimensional Atom Probe (3DAP) experimental observations showed the
formation of spherical γ-precipitates at a central region of γ’ phases in nickel based superalloys. The γ
precipitates should give a significant effect to the material strength. Whereat, in this work, we first
developed a simulation technique for the investigation of the formation of γ-precipitates in γ’ phases,
which is based on a combination of an Embedded Atom Method (EAM) interatomic potential
designed for Molecular Dynamics (MD) and the kinetic lattice Monte Carlo (KLMC) method. As a
demonstration of the KLMC simulation, the formation of the L12 structure was simulated from an
initial state with randomly distributed aluminum atoms (25at.%Al). Finally, the γ’ phase with the L12
structure is formed in the entire simulation volume. To understand the fundamental mechanism of the
formation of the L12 structures, the binding energies between a pair of aluminum atoms in a nickel
single crystal were calculated using MD method. The result gave a clear picture of the mechanism.
The stability of the γ-precipitate was also investigated using the MD method. Finally, the formation of
γ-precipitates was simulated using the KLMC method. The dependence of the formation on the
temperature condition is discussed.
An Adaptive EFG-FE Computational Model for Thermal Elasto-Plastic Frictional Contact Problems
Authors: Zhang Zheng , Liu Geng , Liu Tian Xiang
Published: March 2009

An adaptive meshless element-free Galerkin-finite element (EFG-FE) coupling model for
thermal elasto-plastic contact problems is developed to investigate the influences of the steady-state
frictional heating on the contact performance of two contacting bodies. The thermal elasto-plastic
contact problems using the initial stiffness method is presented. The local adaptive refinement
strategy and the strain energy gradient-based error estimation for EFG-FE coupling method are
combined. The adaptive meshless model takes into account the temperature variation, micro plastic
flow, and the coupled thermo-elasto-plastic behavior of the materials, considering the
strain-hardening property of the materials and temperature-dependent yield strength. The adaptive
model is verified through the contact analysis of a cylinder with an elasto-plastic plane. The thermal
effects on the contact pressure, stresses distributions with certain frictional heat inputs are studied.
The results show that the accuracy of the solutions from the adaptive refinement model is satisfactory
but the cost of the CPU time is much less than that for the uniform refinement calculation.
Development of Parallel CAE System for Large Scale Problems Based on Computer Network
Authors: Shioya Ryuji , Ogino Masao , Fujino Kei , Kanayama Hiroshi , Kawai Hiroshi
Published: March 2009

We have been developing an advanced general-purpose computational mechanics system,
named ADVENTURE, which is designed to be able to analyze a three dimensional finite element
model of arbitrary shape over 100 million Degrees Of Freedom (DOF) mesh. The one of main process
modules for solid analysis, named ADVENTURE_Solid, is based the hierarchical domain
decomposition parallel algorithm and employs the balancing domain decomposition as a solution
technique for linearized equations. The ADVENTURE_Solid has been successfully implemented on
a single PC, PC clusters and MPPs with high parallel performances. Since the software has become a
quite large system, it is not easy to install or operate the system on parallel machines by users. In this
paper, to operate such a system from a client PC through the network, the Web-based CAE system is
developed.
A Modified Model for Simply Supported Ultrathin Films
Authors: Huang Dian Wu , Zhan Feng , Zhu Qi Jian
Published: March 2009

A modified model of simply supported ultrathin film for incorporating the surface effects
and geometrically nonlinear conditions is proposed on basis of Kirchhoff’s hypothesis. The
governing equations and non-classical boundary conditions are derived via using Hamilton’s
principle. The residual membrane force and bending moment, in which the contributions of surface
stresses and nonlinear terms are taken into account, are explicitly expatiated. Comparison between
the modified model and conventional plate theory is also given. Using the simply supported
bending strip-like film as an example, results indicate that the mechanical behaviors of the film are
size-dependent when the thickness of the film is nanometer.
Atomistic Simulation of the Energy Barrier for Dislocation Movement in Si
Authors: Kim S.Y. , Im S. , Earmme Y.Y.
Published: March 2009

We examine the mobility of an edge dislocation pair on the shuffle plane in Si using
action-derived molecular dynamics (ADMD). ADMD is one of the specially designed schemes for
finding out the reaction pathways passing through transition states in the landscape of potential energy
surfaces. Via ADMD calculations, the various structural changes of dislocation line with atomic
resolution and their corresponding energy barriers are evaluated during the dislocation motion. The
energy barrier for the movement of an edge dislocation pair on shuffle plane is about 0.24 eV. In this
case, one bond between the atoms at the dislocation line is broken first, and then a new bond is formed
with the neighboring atom. The movement of the dislocation line is achieved by a sequence of making
new bond after bond-breaking of concerned atoms, which occur layer by layer. When the dislocation
moves through this mechanism, energy barrier for the dislocation movement does not depend on the
length of dislocation line. Thus the present result enables one to surmount the inherent limitation of
Peierls-Nabarro’s two-dimensional continuum model, which may fail to describe successfully
dislocation motion on the atomistic level.
Crack Tip Plasticity By Classic Dislocation Dynamics
Authors: Homma Hiroomi , Tran Huu Nhan
Published: March 2009

Under very short pulse loads in range from 25 to 100 μs, crack tip plasticity a head of the
crack tip in the mode I condition was investigated by discrete dislocation dynamics. The obtained
dislocation array parameters such as the number of dislocations, dislocation distribution density,
crack tip opening displacement and plastic zone size increase with the magnitude of stress intensity
factor, KI and pulse durations. The numerical results were well compared with the experimental
ones.
Water Distribution System Modeling and Remote Monitoring
Authors: Van Blaricum Vicki L. , Hock Vincent F.
Published: March 2009

Localized internal corrosion of water distribution piping is difficult to detect, diagnose, and
mitigate. This paper describes the demonstration and validation of multi-parameter water quality
sensors and corrosion rate sensors that were permanently installed at a U. S. Army installation to detect
corrosion problems and fine-tune the chemical treatment program. This paper will include results of the
sensor demonstration and validation. Follow-on work includes the integration of the sensors with a
dynamic real-time water distribution system chemical and hydraulic simulation. This work will also be
described.
Fatigue Behaviour of Corrosion Resistant Surface Thin Hard Coatings
Authors: Baragetti Sergio
Published: March 2009

Corrosion resistance of metal components and structures can be improved by using thin
hard coatings. Among the coatings recently developed the PVD coatings act as good corrosion
barrier and enable to increase the surface hardness and wear resistance of the coated components.
Appropriately designed PVD coatings can increase the fatigue resistance of mechanical components
too and would enable to enhance the mechanical behaviour in aggressive environments. In this
paper the fatigue behaviour of corrosion resistant surface thin hard coatings is studied. A survey of
recent fatigue test results on steel and light alloys, on coated and uncoated, smooth and notched
specimens, is reported. A numerical procedure to foresee the number of cycle to failure of coated
components is described and applied to spur gears.
LBW of Similar and Dissimilar Skin-Stringer Joints Part I: Process Optimization and Mechanical Characterization
Authors: Prisco A. , Acerra F. , Squillace Antonio , Giorleo G. , Pirozzi C. , Prisco U. , Bellucci Francesco
Published: March 2009

Laser beam welding of light alloys has always represented a big challenge for both
designers and technologists due to the large number of process parameters to take into account and
the variable responses of the different materials to be welded. In this paper the results of
experimental research on laser beam welds of innovative heat treatable aluminum alloys is reported.
The well known T geometry (a stringer welded to a skin) has been considered. Two different skins
have been analyzed: AA 2139 and AA 6156, both in form of rolled sheets. Two different stringer
have been analyzed: AA 2139 and PA 765, both in form of extruded parts. AA 4047 has been used
as filler wire. In the first part of the paper, all the steps leading to the realization of sound welds will
be described. The criteria used in order to assess the soundness of a weld was the absence of
defects, such as cracks or large pores, verified by means of NDE. In the second part of study, both
micro structural analysis and mechanical characterization of welds will be described and discussed.
Conclusions will demonstrate the importance of the influence of chemical composition of the parts,
above all stringer. The performance of the best welds, however, were very close to those of parent
materials.
The Structure-Property Relationship in Oxide Glasses: A Thermodynamic Approach
Authors: Vedishcheva Natalia M. , Shakhmatkin Boris A. , Wright Adrian C.
Published: March 2009

This paper considers a rigorous thermodynamic approach that can be used for calculating
a variety of glass properties and the content of various structural units in glasses. Since both the
properties and the structure are calculated on a unified basis, this approach enables the structureproperty
relationship in glasses to be established quantitatively, and the structural units that
characterise changes in glass properties to be determined.
New Paradigm of Glass Structure and Physicochemical Essence of Glass Transition
Authors: Minaev Victor , Terashkevich Igor , Timoshenkov Sergey , Kalugin Victor , Novikov Sergey
Published: March 2009

The new conception of the polymeric-polymorphoid structure of glass and glassforming
liquid of individual chemical substances (ICS) is presented. The analysis of numerous data of X-ray
diffractometry, DSC, Raman spectroscopy etc. shows that such glassforming ICS as SiO2, GeO2.
H2O, Se, GeS2, GeSe2, As2S3, AsSe, BeCl2 and other are the copolymers of the structural fragments
(polymorphoids) having no translation symmetry of two (or more) polymorphous modifications
(PM) of these substances. The physicochemical essence of glass transition process is discussed.
Poisson's Ratio and the Glass Network Topology - Relevance to High Pressure Densification and Indentation Behavior
Authors: Rouxel Tanguy , Ji Hui , Keryvin Vincent , Hammouda Tahar , Yoshida Satoshi
Published: March 2009

Although Poisson's ratio (ν) is a macroscopic elastic parameter it depends much on the
fine details of the atomic packing. Glasses exhibit a wide range of values for  from 0.1 to 0.4
which correlate to the glass network polymerisation degree, hence reproducing at the atomic scale
what is observed in cellular materials at the macroscopic scale[1]. As for pure oxide glasses, we
found in various multi-component glasses built on ionic-, covalent- or Van der Waals bonds that an
increase of Poisson’s ratio corresponds to a decrease of the atomic network crosslink degree[2].
Noteworthy, an extension of this analysis to the case of metallic glasses correlate the recently
proposed cluster-like network structure for these glasses[3,4]. A general feature is that a highly
cross-linked atomic network results in a glass with a low atomic packing density (large free volume
fraction), as exemplified with the case of amorphous silica. The lower the atomic packing density is
and the larger the volume change the glass experiences under high pressure (1 to 25 GPa).
Indentation experiments with sharp indenters (such as the Vickers one) give birth to hydrostatic
stresses of the same order of magnitude and thus induce glass densification. There is hence a direct
correlation between ν (reflecting the packing density) and the indentation behavior[5].