bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Characterization of PEG-Modified ZnGd0.1Fe1.9O4 Ferrite Nanoparticles for Interstitial Hyperthermia to Tumor
Authors: Yao Ai Hua , Wang De Ping , Huang Wen Hai
Published: March 2009

PEG-modified ZnGd0.1Fe1.9O4 ferrite nanoparticles were synthesized by a coprecipitation
process combined with a microemulsion technique. The effect of modification on the structure,
magnetic properties of ZnGd0.1Fe1.9O4 nanoparticles was also investigated by XRD, FTIR, TEM
and VSM. The results showed immobilizing PEG on the surfaces of magnetic nanoparticles
effectively improved their dispersibility. Magnetic measurements indicated that the as-prepared
PEG-modified nanoparticles exhibited relatively high magnetic properties, although a slight
reduction in saturation and remanent magnetization were observed compared with unmodified
samples. Therefore, with promising high magnetic behavior and potentially good biocompatibility,
PEG-modified ZnGd0.1Fe1.9O4 ferrite nanoparticles would be feasible as thermoseeds for interstitial
hyperthermia to tumor.
Selective Laser Sintering of Tissue Engineering Scaffolds Using Poly(L-Lactide) Microspheres
Authors: Zhou Wen You , Lee S.H. , Wang Min , Cheung W.L.
Published: March 2009

This paper reports a study on the modification of a commercial selective laser sintering
(SLS) machine for the fabrication of tissue engineering scaffolds from small quantities of
poly(L-lactide) (PLLA) microspheres. A miniature build platform was designed, fabricated and
installed in the build cylinder of a Sinterstation 2000 system. Porous scaffolds in the form of
rectangular prism, 12.7×12.7×25.4 mm3, with interconnected square and round channels were
designed using SolidWorks. For initial trials, DuraFormTM polyamide powder was used to build
scaffolds with a designed porosity of ~70%. The actual porosity was found to be ~83%, which
indicated that the sintered regions were not fully dense. PLLA microspheres in the size range of 5-30
μm were made using an oil-in-water emulsion solvent evaporation procedure and they were suitable
for the SLS process. A porous scaffold was sintered from the PLLA microspheres with a laser power
of 15W and a part bed temperature of 60oC. SEM examination showed that the PLLA microspheres
were partially melted to form the scaffold. This study has demonstrated that it is feasible to build
tissue engineering scaffolds from small amounts of biomaterials using a commercial SLS machine
with suitable modifications.
Hydroxyapatite Nano-Particles Coating on the Pore Surface Within Poly(DL-lactic-co-glycolic acid) Scaffold
Authors: Li Jia Shen , Mak Arthur F.T.
Published: March 2009

This paper describes a novel method for coating hydroxyapatite (HA, Ca10(PO4)6(OH)2)
nano-particles onto poly(DL-lactic-co-glycolic acid) (PLGA) scaffold. Paraffin micro-spheres were
used as porogens to create porous scaffolds and as vehicles to transfer HA into PLGA scaffold. HA
nano-particles / 50% ethanol suspension was mixed with paraffin micro-spheres. The paraffin
micro-spheres / HA suspension were pressed together to form a paraffin scaffold. After it was dried,
the HA was coated on the surface of the paraffin spheres. Then, PLGA solution was cast into the
inter space among the paraffin micro-spheres and then the solvent was evaporated. Afterwards, the
paraffin micro-spheres were dissolved and removed. PLGA scaffolds with controlled pore size,
good interconnectivity and high porosity were obtained. The HA nano-particles were transferred
from the paraffin surface to the surface of the pore wall throughout the PLGA scaffold.
Bioinspired Growth of Hydroxyapatite Nanocrystals on PLGA- (PEG- ASP)n Scaffolds Modified with Oligopeptide Derived from BMP-2
Authors: Yuan Quan , Guo Xiao Dong , Zheng Qi Xin , Zhao Ming , Pan Zheng Qi , Chen Shun Guang , Quan Da Ping
Published: March 2009

Natural bone is a typical example of an “organic matrix-mediated” biomineralization
process which constituted of hydroxyapatite(HA) nanocrystals orderly grown in intimate contact
with collagen fibers. Bone morphogenetic protein 2 (BMP2) is the most powerful osteogenic factor.
But it is extremely difficult to be manufactured in large scale. In previous study, we have designed a
novel oligopeptide (P24) derived from BMP2 knuckle epitope and it contained abundant
Asp(aspartic acid) and phosphorylated Ser(serine) which may be helpful for self-assambly
biomineralization and osteogenesis. Previous In vivo experiments have shown that this novel
oligopeptide had excellent osteoinductive and ectopic bone formation property which was similar to
that of BMP2. In this study, PLGA-(PEG-ASP)n scaffolds were modified with P24 and a new
biomimetic bone tissue engineering scaffold material with enhanced bioactivity was synthesized by
a biologically inspired mineralization approach. Peptide P24 was introduced into
PLGA-(PEG-ASP)n scaffolds using cross-linkers. Then the P24 modified scaffolds and the simple
PLGA-(PEG-ASP)n scaffolds were incubated in modified simulated body fluid (mSBF) for 10 days.
Growth of HA nanocrystals on the materials was confirmed by observation SEM and measurements
EDS and XRD. SEM analysis demonstrated the well growth of bonelike HA nanocrystals on P24
modified PLGA-(PEG-ASP)n scaffolds than that of the control scaffolds. The main component of
mineral of the P24 modified scaffolds was hydroxyapatite containing low crystalline nanocrystals,
and the Ca/P ratio was nearly 1.60, similar to that of natural bone, while that of the control scaffolds
was 1.52. The introduction of peptide P24 into PLGA- (PEG- ASP)n copolymer provides abundant
active sites to mediate the nucleation and self- ssembling of HA nanocrystals in mSBF. the resulted
peptide P24 modified- HA/PLGA- (PEG- ASP)n composite shows some features of natural bone
both in main composition and and hierarchical microstructure. This biomimetic treatment provides
a simple method for surface functionalization and subsequent biomineralization on biodegradable
polymer scaffolds for tissue engineering.
Taiwan’s Composites and FRP Industries: Current Status and Future Developments
Authors: Ma Chen Chi M.
Published: March 2009

This presentation will illustrate the history, current status and future development of composite
and FRP industry in Taiwan. This paper will present the characteristics of composites industry in
Taiwan. The statistic survey of market and products of composite will be shown in details. Trend
and development of FRP and Composites will be discussed. Unique products made in Taiwan will
be described by several categories. The challenge and prospective aspects of Composite Industry
will be discussed. Research and Development of Composite in Taiwan are critical to our industry
which will be emphasized. International cooperation has been conducted which will be presented.
Emphasis will be placed on the R&D of composites in Taiwan including: Basic research.
Processing. Nanocomposites. “Green composites” and High-tech applications.
Academia-industry cooperation will be discussed. International cooperation among academic
institute, society/association and foreign industry will also be illustrated.
The Influence of the End of the Incidence Pole on the KId of the Three Point Bending Specimen Tested by the SHPB
Authors: Zhou Guang Ping , Qu Jia
Published: March 2009

When the KId (dynamic fracture toughness) of the three point bending components is
tested on the SHPB device, the signals of reflected waves obtained have been elongated because the
end of the incidence pole is generally made by wedge shape. Through the conduction theory based
on one dimension stress wave theory, the reflection and transmission phenomena of waves on the
surface of the wedge have been analyzed. In the present paper, the loads acting the components
have been modified, by removing the stress wave part among incidence and reflection waves
reflected by the wedge surface.
Study of Amine-Cured Epoxy Resin/Aluminium Oxide Interfacial Interaction
Authors: Mei Lei , Jin Xi Gao , He Xiao Dong , Tang Ya Lin , Xu Jian
Published: March 2009

The interfacial structure and interactions of amine-cured epoxy resin (EP) / aluminium
oxidie system were investigated in this presentation. The competitive chemisorption of uncured
epoxy resin on Al2O3 particles were measured by FTIR and XPS. The interphase structure and the
morphology at different depths of the broken-surface of the samples were characterized by XPS and
SEM. The results showed that the nitrogenous molecules in the system formed the adsorbed
monolayers on the interface based on the coupling interaction of the adsorption and cure. The
composition, binding energy and chemical properties of the interphase deviated considerably from
that of the bulk.
Control of Surface Morphologies and Crystal Structures of Potassium Titanate Fibers by Flux Method
Authors: Liu Chang , Qin Xi Feng , Yang Zhu Hong , Feng Xin , Lu Xiao Hua
Published: March 2009

In this work, flux method is used to control the surface morphologies and crystal
structures of the fine K2Ti6O13 fibers. When K2CO3 as a flux is added into fine K2Ti6O13 fibers and
heated at 1100oC for 2h, the crystal of fibers are transformed to K2Ti4O9 and K2Ti2O5, however, the
resulting fibers have no significant change in morphologies. On the other hand, when KCl is used as
flux (15wt%) and heated at 1200oC for 2h, the diameters of the resulting fibers become about 2
micron without any change of the crystal structure.
A Theoretical Analysis on Resin Injection/Compression Molding
Authors: Shojaei Akbar , Spah A.
Published: March 2009

In the present investigation, mold filling process of resin injection/compression molding
(RI/CM) is compared with resin transfer molding (RTM) for simple mold geometry. To do this,
analytical solutions are obtained for RI/CM in unidirectional flow. Based on the analytical solutions,
flow front progression and pressure distribution are compared with RTM at different fiber content.
The results indicate that the RI/CM reduces the mold filling time significantly, particularly for
composite parts with higher fiber content.
Online Spinning of Commingled Yarns-Equipment and Yarn Modification by Tailored Fibre Surfaces
Authors: Mäder Edith , Rothe Christina , Brünig Harald , Leopold Thomas
Published: March 2009

A unique melt spinning equipment for E-glass is compatibly combined with a melt
spinning extruder to manufacture commingled yarns. The in-situ commingling enables to combine
homogeneously both glass and polypropylene filament arrays in one processing step and without fibre
damage compared to commingling by air texturing. Best composite performance is achieved with a
sizing for glass fibres consisting of aminosilane and maleic anhydride grafted polypropylene film
former, which enable a good strand integrity with the polypropylene yarn. The results of fundamental
research on variation of technological processing conditions like diameter ratios, draw ratios,
variation of cooling conditions and arrangements of intermingling are reported for glass
fibre/polypropylene systems.
Low-Velocity Impact Damage Prediction of Composite Laminates Using Linearized Contact Law
Authors: Choi Ik Hyeon
Published: March 2009

Recently, author had presented that impact force history of composite laminates subjected
to low-velocity impact could be well analyzed using linearized contact law instead of the modified
Hertzian contact law. If the linearized contact law concept is applied in impact response analysis, the
impact problem can be transformed as a general structural analysis problem, so general purpose FEM
software can be used in this kind of impact response analysis. In the present study it will be shown
that impact damage, specially delamination area, as well as impact response can be well analyzed
using the linearized contact law concept. In order to accurately predict delamination area, geometrical
nonlinear analysis considering large deflection effect of plate has been performed and thermal stress
analysis to consider thermal residual strain induced in curing process has been performed. Also, a
proper failure criterion for delamination estimation has been used. In this failure criterion, in-situ
strength values, obtained through matrix crack onset analysis have been used. Finally, analytically
predicted delamination areas have been compared with experimental results. It shows that this
analytical procedure can well predict delamination area of composite laminates subjected to the
low-velocity impact.
Modeling of Manufacturing Processes of Carbon Matrices Composites and Prediction of Mechanical Properties of Materials during the Process
Authors: Liang Jun , Yang Wei , Wang Bao Lai , Du Shan Yi
Published: March 2009

Carbon-carbon composites are widely applied in the area of astronautics and aeronautics.
As a kind of advanced composites, its properties are known to depend essentially on the technological
regimes of its manufacturing processes. This paper is devoted to the modeling of manufacturing
processes of the composites and focuses on establishing the processing-microstructure-property
relation to enable design of internal architecture to predict and optimize properties.
Behaviour of Composite Materials to Withstand Impact and Compressive Design Allowables
Authors: Shen Zhen , Yang Sheng Chun , Chen Pu Hui
Published: March 2009

In this paper the relationship between CAI and compressive design allowables of
composite structures were discussed and it was pointed out that traditional CAI values could not
reflect the behavior of composite materials to withstand impact adequately and no relationship
between CAI values and compressive design allowables existed. Based on the integrity requirements
of composite structures, it was pointed out that the evaluation system of composite materials to
withstand impact should include both damage resistance and damage tolerance. Large numbers of test
data verified that the knee point phenomenon of composite laminates to withstand impact existed.
Based on failure mechanisms, it was proposed that the behavior evaluation system of composite
systems to withstand impact was based on the properties at the knee point, that is, the maximum
capability to keep integrity of the front plies (the maximum contact force) characterizing damage
resistance and the threshold of dent depth(or impact energy)~compressive strength(or failure strain)
curves characterizing damage tolerance.
Structural Safety Evaluation of the Hybrid Composite Bodyshell for Korean Tilting Train by a Whole Body Test
Authors: Kim Jung Seok , Jeong Jong Cheol , Lee Sang Jin , Cho Se Hyun , Yoon Sung Ho , Han Seong Ho , Seo Sung Il
Published: March 2009

This paper explains the structural safety evaluation of a hybrid composite train carbody.
The composite carbody with length of 23m was manufactured as a sandwich structure composed of a
40mm-thick aluminum honeycomb core and 5mm-thick woven fabric CF1263 carbon/epoxy face. In
order to evaluate the structural safety of it, the dynamic force of ±0.2g was applied to the full weight
carbody by two 50-ton capacity hydraulic actuators. The excitation frequency was determined by the
first bending natural frequency evaluation test under full weight condition. The test was conducted for
2x106cycles. During the test, the nondestructive tests using X-ray for the composite body structure
and liquid penetrant test for the welding region of the steel underframe were performed.
Effect of Fiber Content and Fiber Orientation on the Tensile Strength in Glass Mat Reinforced Thermoplastic Sheet
Authors: Kim Jin Woo , Lee Dong Gi
Published: March 2009

The study for strength calculation of one way fiber-reinforced composites and the study
measuring precisely fiber orientation distribution were presented. Need the systematic study for the
DB that can predict mechanical properties of composite material and fiber orientation distribution by
the fiber content ratio was not constructed. Therefore, this study investigated what affect the fiber
content ratio and fiber orientation distribution have on the strength of composite sheet after making
Glass Mat Reinforced Thermoplastic Sheet by changing fiber orientation distribution with the fiber
content ratio. The result of this study will become a guide to design data of the most suitable parts
design or fiber reinforced polymeric composite sheet that uses the Glass Mat Reinforced
Thermoplastic Sheet in industry part, because it was conducted in terms of developing products. It
studied the effect the fiber orientation distribution has on tensile strength of Glass Mat Reinforced
Thermoplastic Sheet and achieved this result below. The increasing range of the value of Glass Mat
Reinforced Thermoplastic Sheet’s tensile strength in the fiber orientation direction is getting wider as
the fiber content increases.
Conceptual Design on Carbon-Epoxy Composite Wing of a Small Scale WIG Vehicle
Authors: Kong Chang Duk , Park Hyun Bum , Yoon Jae Huy , Kang Kuk Jin
Published: March 2009

Conceptual structural design of the main wing for the 20 seats WIG(Wing in Ground
Effect)flight vehicle, which will be a high speed maritime transportation system for the next
generation in Rep. of Korea, was performed[1,2]. The high stiffness and strength Carbon-Epoxy
material was used for the major structure and the skin-spar with a foam sandwich structural type was
adopted for improvement of lightness and structural stability. As a design procedure for this study,
firstly the design load was estimated through the critical flight load case study, and then flanges of the
front and the rear spar from major bending loads and the skin structure and the webs of the spars from
shear loads were preliminarily sized using the netting rule and the rule of mixture[4,5].
In order to investigate the structural safety and stability, stress analysis was performed by commercial
Finite Element code such as NASTRAN/PATRAN. From the stress analysis results, it was confirmed
that the upper skin structure between the front spar and rear spar was weak for the buckling. Therefore
in order to solve this problem, a middle spar and the foam sandwich structure at the upper skin and the
web were added. After design modification, even thought the designed wing weight was a little bit
heavier than the target wing weight, the structural safety and stability of the final design feature was
confirmed. In addition to this, the insert bolt type structure with six high strength bolts to fix the wing
structure at the fuselage was adopted for easy assembly and removal. As well as consideration of the
fatigue limit load for more than 20 years fatigue life.
Static Compressive Strength of Unidirectional Carbon Fibre-Epoxy Laminate
Authors: Lee Joung Hwan , Soutis Costas , Kong Chang Duk
Published: March 2009

Existing test methods for thick-section specimens (≥ 4[mm]) have not provided
precise compressive properties to date for the analysis and design of thick structure. In the
current study, the cause of the premature failure for thick specimens (T800/924C and
IM7/8552) was identified experimentally and numerically. The premature failure was
successfully avoided during compressive testing and the failure mode was quite similar
regardless of increasing specimen thickness and specimen volume. Furthermore it was
identified that the failure location within gauge section does not have an influence on the
compressive strength from the experimental result performed with the unwaisted specimens
and the waisted specimens. Finally, clear 1-D thickness and 3-D scaling effects on the
compressive strength of unidirectional composite laminates existed. The main factors
influencing the effects were due to manufacturing defects such as void content and fibre
waviness.
Improvement of Mechanical Properties of Curaua Fiber Green Composites
Authors: Matsuo Takanori , Gomes Alexandre , Goda Koichi , Ohgi Jun Ji
Published: March 2009

Environment-friendly green composites were developed by combining a biodegradable
resin with curaua fibers. The composites were fabricated by three different methods, i.e. direct,
pre-forming and prepreg sheets methods. Mechanical properties of composites fabricated by all
three methods were evaluated through tensile test. Moreover, green composites reinforced by fibers
treated with high concentration alkali solution were fabricated by pre-forming and prepreg sheets
methods. The results showed that fracture strain of alkali-treated fiber composites increased twice to
three times larger than that of untreated-fiber composites. Finally, effect of cyclic load application
on tensile strength of curaua single fibers was investigated.
Finite Element Analysis of Wave Transmission through a Unidirectional Composite Layer
Authors: Biwa Shiro , Nakashima Kazuhiro , Matsumoto Eiji
Published: March 2009

Elastic wave transmission characteristics through a fiber-reinforced composite layer are
studied by the two-dimensional steady-state finite element analysis. To this purpose, boundary
conditions are formulated which account for the connection of the model domain to the semi-infinite
regions as well as a certain periodicity of the fiber arrangement. The transmission characteristics
through a composite layer are computed for the longitudinal and transverse wave incidence, assuming
a finite number of fiber alignments in a square array. The analysis delineates the existence of clear
stop bands in the case of transverse wave incidence, even with a few lines of fibers aligned normal to
the propagation direction. These stop bands are discussed on the basis of the interference effects of
neighboring fiber alignments as well as neighboring fibers in each alignment.
Liquid Nitrogen Storing and Pressurization Test of a Type III Cryogenic Propellant Tank
Authors: Kang Sang Guk , Kim Myung Gon , Park Sang Wuk , Kim Chun Gon , Kong Cheol Won
Published: March 2009

Nowadays, researches for replacing material systems for cryogenic propellant tanks by
composites have been being performed for the purpose of light weight of a launch vehicle. In this
paper, a type III propellant tank, which is composed of the composite developed for cryogenic use and
an aluminum liner, was fabricated and tested considering actual operating environment, that is,
cryogenic temperature and pressure. For this aim, liquid nitrogen (LN2) was injected into the
fabricated tank and in turn, gaseous nitrogen (GN2) was used for pressurization. During this test
procedure, strains and temperatures on the tank surface were measured. ESG (electric strain gage) and
thermocouple were used for the measurement of strain and temperature, respectively. Delamination
between hoop layer and helical one, was detected during the experiment. Finally, Tsai-Wu criterion
for the tank and microscopy for the composite/aluminum ring specimen were carried out to
investigate the reason why delamination had happened.
Damage Characteristics of Cross Ply GFRP and Woven AFRP under Various Impact Velocities
Authors: Kim Cheol Woong , Lee Sung Hyuk , Lee Sang Heon , Kim Kee Joo
Published: March 2009

Ankle Foot Orthosis (A.F.O) should endure the uncountable repeating impact and fatigue
loadings due to the gait characteristics. This study investigated the impact deflection and relationship
between the absorbed energy and the residual strength rate using the cross ply GFRP (glass/epoxy)
and the woven AFRP (aramid/epoxy) for the leaf spring in A.F.O. In conclusion, the equation was
suggested to evaluate the absorbed energy and the residual strength rate by the different impact
velocities. When the cross ply GFRP and the woven AFRP was selected for the leaf spring in A.F.O,
it was reasonable to use the cross ply GFRP for the parts subject to the large impact and the woven
AFRP for the parts to require the high elastic energy such as the large deformation.
Modified Bernoulli-Euler Laminate Beam Theory Using Total Effective Moment in LIPCA
Authors: Kim Cheol Woong , Lee Sang Heon , Kim Kee Joo
Published: March 2009

The applicable bending moment equation of LIPCA is necessary even though the fiber
layer ply orientation is changed. The aim of this research is to evaluate the relationship between the
total effective moment (ME) and Bernoulli-Euler bending moment (M) when the ply orientations of
unidirectional CFRP, which is one of the various laminate configurations in LIPCA, are changed.
Since the related previous equation between the performance stroke range (h) and the radius of
curvature (ρ) was just applicable to the CFRP ply orientation [0], it will be modified using these
results. The related modified equation, which has nothing to do with the various CFRP ply orientation,
is also suggested and compared with the previous equation.
Evaluation of Interfacial Reaction between Titanium Matrix Composites and Aluminium Alloy
Authors: Choi Bong Jae , Sung Si Young , Kim Young Jig
Published: March 2009

The main purpose of this study is to evaluate the interfacial reaction between titanium
matrix composites (TMCs) and A380 alloy in aluminum die-casting. In-situ synthesized titanium
matrix composites and H13 tool steel were immersed in molten A380 alloy in a mold at 993 K for
times varying from 0 to 1200 s. In-situ synthesis TMCs and interfacial reaction between TMCs and
A380 alloy were examined by X-ray diffraction, optical microscope, scanning electron microscope
and electron probe micro-analyzer. The reaction behavior shows that TMCs can a substitution for
H13 tool steel.
Fatigue Life Prediction of CFRP Laminates under Variable Stress Amplitude and Frequency
Authors: Nakada Masayuki , Noda Junji , Miyano Yasushi
Published: March 2009

This paper is concerned with the fatigue life prediction of CFRP laminates under variable
cyclic loading using the linear cumulative damage (LCD) rule with statistical approach. Three-point
bending fatigue tests for plain-woven CFRP laminates were carried out undervarious cyclic loading
with constant and variable stress amplitude and frequency. As results, the applicability of LCD rule to
the flexural fatigue life was confirmed for this CFRP laminates.
Damage Tolerance of Carbon Fabric/Epoxy Composite for Korean Tilting Train Carbody
Authors: Yoon Sung Ho , Heo Kwang Su , Oh Jin Oh , Jeong Jong Cheol , Lee Sang Jin , Kim Jung Seok , Han Seong Ho
Published: March 2009

Interlaminar fracture behavior of carbon fabric/epoxy composite, which is one of the candidate composites for the Korean tilting train carbody, was investigated. Specimens were made of a CF3227 plain fabric with an epoxy resin. An initial starter crack was formed by inserting a 12.5 thick Teflon film at the one end of the specimen. Interlaminar fracture toughness was evaluated using the mixed mode flexural fixture, which provides a wide range of mixed mode deformation by varying the length of lever arm. According to the results, the crack growth was progressive and stable under mode I dominantly mixed mode ratio and was relatively rapid and unstable under mode II dominantly mixed mode ratio. The mixed mode interlaminar fracture behavior can be predicted by a mixed mode fracture criterion depending on the point at which the crack growth was associated.
Composite Structure Optimization Design System Based on Grid Technology
Authors: Cheng Wen Yuan , Cui De Gang , Chang Yan , Xie Xiang Hui
Published: March 2009

In the traditional iterative design process for composite structures, it is difficult to achieve
an optimal solution even though a great effort is made. A genetic optimization system based on grid
technology offers an automatic and efficient approach for composite structure redesign and
optimization. A genetic algorithm system, which integrates Genetic Algorithm Optimization (GAO)
software and a Finite Element Analysis (FEA) based commercial package, has been developed as a
tool for composite structure design and analysis. The GAO is capable of tailoring large number of
composite design variables and taking the time-consuming FEA results to calculate objective function
value and conduct optimization in high accuracy. By operating the system employing the Grid
technology and Artificial Neural Network (ANN) method, significant time saving in numerical
analysis can be achieved. A user friendly interface has also been built in the system. In the paper,
aeroelastic tailoring of a composite wing has been taken as a numerical example to demonstrate the
optimization approach. The numerical results show that an optimal design has been achieved to meet
the design requirement.
Development of Composite Optical Bench Structures on a Satellite Considering Launch and Space Environments
Authors: Kim Cheol , Kim Sun Goo , Kim Yong Yun
Published: March 2009

Satellite structural components must be able to withstand various loading and
environments that will experience during integration, tests, transportation, launch, and on-orbit
operation. A polymeric composite optical bench that fixes delicate optical payloads such as a camera
or a telescope was developed based on static strength, thermal deformation, and vibration. The optical
bench consists of composite sandwich panels with and without a hole and composite struts with end
fittings. In this paper, the optimum stacking sequence of the composite optical bench was calculated
to minimize severe thermal deformations during orbital operation using a genetic algorithm and the
finite element analysis. Then, the optimum design is evaluated whether it withstands launch loads
(high inertia, vibration, etc.), that are not usually significant compared to orbital thermal loadings, or
not. The thermal deformation of sandwich panels was minimized at the stacking sequence of [0/±45]s
and that of composite struts was lowest at the angle of [02/90]s. There was no buckling in the
compressive loading. By vibration analysis, the natural frequencies of the composite components
were much higher than aluminum structures (i.e., sandwich panel: 10.7%; strut: 27.79%) and the
stiffness condition expected was satisfied. Then, a composite optical bench was fabricated for tests
and all analyses results were verified by structural testing. There were good correlations between two
results. To increase the structural stiffness, several Nitinol shape memory alloy wires installed on it
and the natural frequencies were measured.
Weight Optimization of Composite Flat and Curved Wings Satisfying Both Flutter and Divergence Constrains
Authors: Kim Dong Hyun , Oh Se Won , Lee In , Kweon Jin Hwe , Choi Jin Ho
Published: March 2009

Aeroelastic tailoring studies using effective computational method with genetic algorithm
have been conducted to find an optimized lamination set which give minimum structural weight. The
efficient and robust computational system for the flutter optimization has been developed using the
coupled computational method based on the micro genetic algorithm. It is shown that the wing
structural weight with both divergence and flutter constrains can be significantly reduced using
composite materials with proper optimum lamination compared to the case of isotropic wing model.
Process-Induced Stress Analysis of Composite Wound Vessel with Metal Liner during Curing Process Using Semi-Analytical Hamiltonian Method
Authors: Ren Ming Fa , Chen Hao Ran
Published: March 2009

In accordance with Helliger-Reissner variational principle, a semi-analytical Hamiltonian
method has been developed for analyzing the process-induced stress analysis of composite wound
vessel with metal liner during the curing process. A typical numerical result indicates that the
process-induced thermo-stress fields involve complex variations of gradient and multi-peak values
at different stages during the curing process.
Fabrication and Properties of Absolutely Recycled Plastic Wood Composites
Authors: Cui Yi Hua , Lee Stephen , Noruziaan Bahman , Cheung Moe M.S. , Tao Jie
Published: March 2009

In this study, the absolutely recycled plastic wood (ARCPW) was fabricated with post-consumer high density polyethylene (HDPE) and wood flour from the saw mills. The alkaline, silane and maleic anhydride modified polypropylene (MAPP) were used as modifiers to treat wood fiber and improve the interfacial adhesion of ARCPW. Effects of wood fiber length, weight fraction and surface treatment on the mechanical properties of ARCPW were investigated. The flexural fracture surfaces of ARCPW were examined and the fracture mechanism of ARCPW was also analyzed in this paper. The results indicated that ARCPW with wood fiber simultaneously treated by alkaline, silane and MAPP possesses the best mechanical properties. The higher the content of wood fiber, the better the flexural strength of ARPCW. The interfacial adhesion of prepared ARCPW is ideal and a good compatibility between wood fiber and matrix was obtained.
Fracture Toughness of Carbon Fiber Reinforced Composites with Rubber Modification
Authors: Takemura Kenichi
Published: March 2009

Fracture toughness and the possibility of recycling for Carbon Fiber Reinforced Plastics (CFRP)
under mode one and mode two loadings are examined. Epoxy matrix is modified by CNBR rubber
particle which diameter is smaller than 100 nano meter. Three kinds of rubber content (5,10,15%) are
used. Two types of test methods whose modes are different are conducted. After the specimen fracture,
recycled specimens are made by adhesion. Fracture toughness is measured at the tests. Fracture
surface is also observed by SEM. As a result, following conclusions are obtained. When the
interlaminar fracture test using recycled CFRP specimen is conducted under Mode one loading,
fracture toughness is improved using rubber modified matrix. For recycled CFRP specimen under
mode two loading, fracture toughness of CFRP using unmodified epoxy is improved. In this case,
fracture toughness for modified CFRP is improved but it is not as high as than CFRP with unmodified
recycle CFRP. From SEM ovservation on fracture sufface under mode two loading, there is a
difference on fracture surfaces. Specimen whose fracture toughness is high has a ductile properties.
Analysis of Potential Energy Release Rate of Composite Laminate Based on Timoshenko Beam Theory
Authors: Kondo Kyohei
Published: March 2009

The Timoshenko beam theory is used to model each part of cracked beam and to
calculate the potential energy release rate. Calculations are given for the double cantilever beam
specimen, which is simulated as two separate beams connected elastically along the uncracked
interface.
Effect of Input Electric Field on Fatigue Degradation of Piezoelectric Fibre Bridging Force
Authors: Gu Bin , Liu Hong Yuan , Mai Yiu Wing
Published: March 2009

Based on our previous model on piezoelectric fibre pullout, the effects of electric input
and piezoelectric parameters on the fatigue degradation on piezoelectric fibre bridging force are
discussed. Numerical results indicate that an electric field can promote or impede the degradation,
depending on its direction. It is also shown that piezoelectric parameters play important roles on the
degradation. Also, comparisons between the effects of electric load and piezoelectric parameters on
fatigue degradation of pullout force and those on pullout force obtained in previous work are carried
out.
Spherical Indentation of Superelastic Shape Memory Alloys
Authors: Yan Wen Yi , Sun Qing Ping
Published: March 2009

Spherical indentation of superelastic shape memory alloys (SMAs) has been theoretically
analyzed. Two characteristic points on the superelastic indentation curve have been discovered. The
bifurcation force corresponding to the bifurcation point relies on the forward transformation stress
and the return force corresponding to the return point relies on the reverse transformation stress.
Based on these theoretical relationships, an approach to determine the transformation stresses of
superelastic SMAs has been proposed. To improve the accuracy of the measurement, a slope method
to locate the two characteristic points from the slope curves is further suggested. Additionally, the
spherical indentation hardness was also analyzed.
Wear Resistance of Organic Nanocomposites
Authors: Zhu Hong Gang , Woo Ricky S.C. , Leung Christopher K.Y. , Kim Jang Kyo
Published: March 2009

The wear resistance of epoxy-based nanocomposites reinforced with
octadecylamine-modified clay was studied. Two testing methods, including the ball-on-disc
abrasion test and the nanoscratch test, were used to measure the macro- and micro-wear behaviors.
The ball-on-disc abrasion test suggests that the short- and long-term wear behaviors of neat epoxy
and 5wt% nanoclay composites were similar, although the wear resistance as measured by the
volume of material removed was greater for the clay nanocomposite than for the neat epoxy. The
incorporation of nanoclay into the epoxy showed little effect on the coefficient of friction.
Synthesis and Properties of Recycled Paper-Nano-Clay-Reinforced Epoxy Eco-Composites
Authors: Low It Meng , Somers Jacob , Pang Wei Kong
Published: March 2009

Epoxy ecocomposites reinforced with recycled paper (rP) and nano-kaolinite (nK) have
been synthesized. The effect of seawater soaking on the flexural and impact properties have been
characterized. This new but cost-effective approach has been developed to improve the physical and
mechanical properties of polymeric materials without adversely affecting their processing
characteristics. The micromechanisms of toughening and failure processes are discussed.
Numerical Investigation of Post Buckling Strength and Failure Modes in Advanced Grid Stiffened Structure under Thermal-Mechanical Loads
Authors: Bai Ruixiang , Chen Bo , Yan Cheng , Ye Lin , Li Ze Cheng , Chen Hao Ran
Published: March 2009

This work investigated the post buckling strength and failure behavior of advanced grid
stiffened structures (AGS) under thermal-mechanical load using a finite element method. Based on
the first order shear deformation theory (FSDT), Von Karman non-linear deformation assumption,
and a progressive failure criterion, the buckling, large deformation，local failure modes in the AGS
were studied. The thermal effect was also analyzed. By some numerical examples, the failure
characteristics of the AGS were discussed.
A Numerical Study of Combined Rate, Size and Thermal Effects on the Responses of Ultrananocrystalline Diamond
Authors: Shen Lu Ming , Chen Zhen
Published: March 2009

To better understand the responses of ultrananocrystalline diamond (UNCD) under
extreme working conditions, a numerical study is performed to investigate the size, loading rate and
thermal effects on the material properties of UNCD films. A combined kinetic Monte Carlo (KMC)
and molecular dynamics (MD) method is first applied to simulate the growth of polycrystalline
UNCD films. The responses of the resulting UNCD films with various grain sizes are then
investigated by applying displacement–controlled tensile loading with different rates and
temperatures in the MD simulations. The preliminary results presented in this paper provide a better
understanding of the combined size, rate and thermal effects on the material properties of UNCD.
Evaluation of Interfacial Properties of Sisal Fiber Reinforced High Density Polyethylene (HDPE) Composites
Authors: Li Yan , Deng Hong Xia , Yu Ye Hong
Published: March 2009

Statistical methods were employed to study the structure characteristics of sisal fibers.
Two types of fiber surface treatment methods, namely chemical bonding and oxidization were used
to improve the interfacial bonding properties of sisal fiber reinforced HDPE (sisal/HDPE)
composites. Interfacial properties were evaluated by single fiber pull out test. The interfacial shear
strength (IFSS) was calculated and analyzed by the statistical parameters. The results were
compared with those obtained by traditional ways. A novel method which could more accurately
evaluate the interfacial properties between natural fiber and polymeric matrices was proposed.
Effect of Stress Singularity on Stress Distribution and Initial Debonding of Interface End
Authors: Dai Ying , Ji Xing , Jiang Guo Dong
Published: March 2009

Interfacial stress distribution of bonded quarter planes subjected a concentrated force was
re-investigated based on Bogy’s solution [1]. It’s found that the characteristic length of the
singularity of interface end (δ), varies with the index of stress singularity at interface end from
millimeter to nanometer. This is a unique characteristic of stress singularity at interface end. How the
characteristic length of the singularity of interface end (δ) influences the initial de-bonding of the
interface end is a new question worth to pay attention. It’s found in the photoelasticity experiments
that usually the debonding initiated at the interface end with singularity, but as the index of stress
singularity, as well as the characteristic length of singularity of interface end, decrease to some extent,
the initial debonding moves to an inner point near the interface end. This phenomenon clearly shows
the index of stress singularity has obvious influence on the debonding of interface end.
Biosensor Application of Enzyme-Functionalized Titania/Titanium Composite
Authors: Xie Yi Bing , Zhou Li Min , Huang Hai Tao
Published: March 2009

Highly-ordered titania nanotube array has been fabricated by a potentiostatic anodization
process in acidic fluoride electrolyte. Calcination at high temperature is followed to achieve
crystallization from amorphous to anatase phase. The approach of embedding bioactive enzymes
inside titania tubule channels has been applied for bioactivation modification of titania/titanium.
The electropolymerization process is applied by using conductive pyrrole monomer to achieve
surface immobilization of enzymes to improve interfacial connection. Characterizations including
field emission scanning electron microscopy, nano-indentation and linear sweep voltammetry
measurements have been performed to fully evaluate the surface morphology, nanomechanical and
electrochemical properties of this composite. Molecule detection application has been investigated
by applying such an enzyme-titania/titanium composite.
Off-Axis Creep Recovery of Unidirectional Carbon/Epoxy Composites at High Temperature
Authors: Kawai Masamichi , Kamioka H. , Zhang Jian Qi , Matsuda Tetsuya
Published: March 2009

Off-axis creep recovery behavior after complete unloading during creep at a constant
stress is examined for a unidirectional T800H/3631 carbon/epoxy composite laminate at high
temperature. Creep and creep recovery tests are performed on plain coupon specimens with four
kinds of fiber orientations: 10, 30, 45 and 90°. It is observed that the creep strain appeared at a high
stress does not completely recover after full removal of the creep stress, indicating that an
irrecoverable creep strain has developed under the prior constant stress loading. Variable stress
creep simulations are attempted using the modified kinematic hardening model for homogenized
anisotropic inelastic composites in which an accelerated change in kinematic hardening over a
certain range of viscoplastic strain is considered. Comparison with experimental results
demonstrates that the proposed model can adequately describe the off-axis creep and creep recovery
behaviors of the unidirectional composite system under constant and variable stress conditions.
Atomic/Continuum Transition at Interfaces of Nanocomposite Materials
Authors: Pyrz Ryszard , Bochenek Bogdan
Published: March 2009

A number of micromechanical investigations have been performed to predict behaviour of
composite interfaces, showing that the detailed behaviour of the material at these interfaces
frequently dominates the behaviour of the composite as a whole. The interfacial interaction is an
extremely complex process due to continuous evolution of interfacial zones during deformation and
this is particularly true for carbon nanotubes since the interfacial interaction is confined to the
discrete molecular level. The atomic strain concept based upon Voronoi tessellation allows
analysing the molecular structure atom by atom, which may give a unique insight into deformation
phenomena operative at molecular level such as interface behaviour in nanocomposites.
Nano-Mechanical Creep Properties of Nanoclay/Epoxy Composite by Nanoindentation
Authors: Lam Chun Ki , Lau Alan Kin Tak , Zhou Li Min
Published: March 2009

Mechanical properties of nanoclay/epoxy composites (NC) have been studied by various
experimental setups in bulk form recently. Creep mechanism of the NC is an important manufacturing
criterion for the aircraft industry. In this paper, nanoindentation was employed to investigate the
nano-mechanical creep effects on different wt. % of nanoclay contents in epoxy matrix. Creep
behaviors of the nanoclay/epoxy composites with different wt. % of nanoclay contents were modeled
by the power-law creep equation. Neglecting the temperature effects on creep, the stress exponents of
tested composites were estimated.
Formation Mechanism and Microwave Permittivity of Carbon Nanotubes Filled with Metallic Silver Nanowires
Authors: Zhao Dong Lin , Li Xia , Chi Wei Dong , Shen Zeng Min
Published: March 2009

The filling of multi-walled carbon nanotubes (MWNTs) with metallic silver nanowires
via wet chemistry method was investigated. The carbon nanotubes were filled with long continuous
silver nanowires. The carbon nanotubes were almost opened and cut after being treated with
concentrated nitric acid. Silver nitrate solution filled carbon nanotubes by capillarity. Carbon
nanotubes were filled with silver nanowires after calcinations by hydrogen. The diameters of silver
nanowires were in the range of 20-40nm, and lengths of 100nm-10μm. We studied the
micromorphology of the silver nanowires filled in carbon nanotubes by transmission electron
microscopy (TEM) and X-ray diffraction (XRD). Based on the experimental results, a formation
mechanism of the Ag nanowire-filled carbon nanotubes was proposed. And the microwave
permittivity of the carbon nanotubes filled with metallic silver nanowires was measured in the
frequency range from 2 GHz to 18 GHz. The loss tangent of the carbon nanotubes filled with
metallic silver nanowires is high. So the carbon nanotubes filled with metallic silver nanowires
would be a good candidate for microwave absorbent.
Tribological and Mechanical Properties of PTFE Composites Filled with the Combination of Short Carbon Fiber and Carbon Nanofiber
Authors: Shi Yi Jun , Feng Xin , Wang Huai Yuan , Lu Xiao Hua
Published: March 2009

The tribological and mechanical properties of polytetrafluoroethylene (PTFE)
composites filled with carbon nano-fiber (CNF), short carbon fiber (SCF) and the combination of
them were studied. The results indicate that the wear volume loss of the PTFE composite filled
with CNF or SCF, in comparison with that of pure PTFE, decreases by 1~2 orders of magnitude.
And the best wear resistant composition is achieved by the combination of SCF with CNF; as an
example, PTFE+2 wt% CNF+18 wt% SCF exhibits a specific wear volume loss of 0.88 mm3,
which is about 11 times lower when compared to the PTFE composite filled with 18 wt% SCF.
Meanwhile, the results also show that the tensile strength of SCF or CNF filled PTFE composites
is better than that of pure PTFE. However, the combination of the two fillers decreases the
tensile strength of PTFE composites. Worn surfaces were investigated using a scanning electron
microscope, from which it is assumed that a mechanism of rolling effect, due to the filling of
nanoparticles, which has a positive protective effect for PTFE matrix.