bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Nondestructive Detecting Technology for Geological Radar in a Large-Scale Highway Lanslide Treatment
Authors: Zhang Qiang Yong , Xiang Wen , Li Xiao Jing
Published: March 2009

The geological radar is an advanced non-destructive geophysical prospecting technology
used in detecting the invisible and abnormal underground objects. In this paper, this technology is
used in the large-scale highway landslide treatment. The location and size of the cavity, fissure and
fracture zone in the landslide body is identified accurately. The supporting design and reinforcement
construction for the landslide is performed according to the testing results, which ensures the slope
stability and the normal operation of the highway, and significant economic benefits have been
achieved.
Experimental Verification and Theoretical Analysis on Felicity Effect of Acoustic Emission in Concrete
Authors: Yuan Rui Fu , Li Yuan Hui , Zhao Xing Dong
Published: March 2009

The experiment of acoustic emission (AE) on concrete specimens under uniaxial cyclic
loading was conducted. The Kaiser effect of acoustic emission in concrete and the Felicity effect,
which manifest the memorizing ability to the maximum previous stress level of Kaiser effect, were
validated by the experiment. The mechanism of Felicity effect was analyzed based on the theory of
statistical damage mechanics and a tentative AE factor constitutive model of brittle material under
uniaxial cyclic loading was suggested. The curve of constitutive model is in good coincidence with
the curve from the experiment. The experimental results showed that the Felicity effect became
clearer along with the increasing of stress level. Each loading cycle would cause new damage inside
the material, and the response of material to the new loading cycle is different from the previous cycle.
Measurement of Acoustic Impedance of Thin Polymeric Films by Acoustic Resonant Spectroscopy
Authors: Tohmyoh Hironori , Imaizumi Takuya , Saka Masumi
Published: March 2009

An acoustic resonant spectroscopy technique for measuring the acoustic impedance of
micron-scale polymer films without knowing any values of ultrasonic velocity, thickness and density
has been developed. The method, which is based on spectral analysis, observes the acoustic resonance
between water, the film and a tungsten plate with high acoustic impedance. The acoustic impedances
of poly(vinyl chloride), poly(vinyl alcohol) and nylon films are determined by the spectroscopy
technique. Moreover, the values of ultrasonic velocity and density of the films are also determined
from the resonance frequencies of the films.
Investigations on Fatigue Properties of Die Cast Magnesium Alloy AZ91HP at Very High Cycles
Authors: Li Tang , Wang Qing Yuan , Dou Q.F. , Wang Chong , Sriraman M.R.
Published: March 2009

Very high cycle fatigue (VHCF) properties of high-pressure die cast Magnesium alloy
AZ91HP have been investigated. Ultrasonic fatigue tests up to 109 cycles were conducted at the
loading frequency of 20 kHz, under R=-1 condition and in ambient air. The experimental results
show that specimens fail even after 107 cycles although the scatter seems to be large probably due
to the presence of materials defects. However, there seems to be a fatigue limit at about 109 cycles.
The fractures contain typical brittle features, with the fatigue cracks seen to initiate from the
porosity in the material, either from the surface or beneath.
A Study of Magnetic Charge per Unit Area of Dipole Model for the NDE
Authors: Hwang Ji Seong , Jun Jong Woo , Choi Se Ho , Kim Cheol Woong , Ogawa Kazuhiro , Lee Jin Yi
Published: March 2009

Nondestructive testing using magnetic field is useful for detection of a crack on
ferromagnetic material. The magnetic field distribution has to be obtained for quantitative evaluation
of crack direction, size, and shape. Also, a crack can be evaluated by using the inverse problem
analysis. However, an analysis method using a dipole model can be used to analyze the magnetic field
distribution around a crack at a higher speed than the finite element method (FEM). Therefore, a
dipole model simulation can provide useful information which can be used for the inverse problem
analysis. However, the magnetic charge per unit area, m, and the permeability, μ, has been treated as
constants. Therefore, analyzed results have been different from experimental results in most cases.
This paper proposes the improved dipole model simulation method, which assumes that the magnetic
charges per unit area exist at the section areas, edge lines and summits of a crack. Also, the magnetic
charges per unit area were assumed to depend on the square of the crack depth. The improved method
is validated by comparing its results with the experiment results obtained with the use of the magnetic
camera.
Pressurized Water Corrosion Resistance of Carbon Steels and Their Nondestructive Characterization
Authors: Lee Sang Ll , Lee Jin Kyung , An Tae Soo , Lee Joon Hyun , Park Jun Young
Published: March 2009

This study dealt with the corrosion resistance for the carbon steels under a pressurized
water atmosphere at the elevated temperature. The nondestructive test was also used to evaluate the
damage degree of corrosion test specimen. The corrosion test for carbon steels was carried out at the
temperature of 200 °C under a water pressure of 10 MPa. The corrosion time for carbon steel was
changed up to 20 weeks. The strength of carbon steel by the degree of corrosion was investigated by a
tensile test. The carbon steel showed an average tensile strength of about 500 MPa after the corrosion
period of 20 weeks, accompanying the weight loss of about 2.5 %. The attenuation coefficient of
ultrasonic wave can be utilized as useful parameters to inspect the corrosion damages of carbon steels.
Fatigue Properties of Austenitic Stainless Steel with Circumferential Notch
Authors: Hattori Nobusuke , Nishida Shinichi , Yano Y. , Ding J.
Published: March 2009

The effect of stress concentration factor on the fatigue properties of typical austenitic
stainless steel SUS304 have been investigated using the circumferentially notched specimens. The
notch of specimens has six kinds of radii, i.e. ρ = ∞ (i.e. plain specimen), 2.0, 1.0, 0.6, 0.3, and 0.1 mm
with constant notch depth (t=0.2mm). Though the fatigue cracks in the specimens with a blunt notch
initiate at one point, those in the specimens with a sharp notch initiate at several points. There exist
the slip bands in the surface of the specimen under the stress amplitude of fatigue limit by 1×107
cycles, and do not exist the non-propagating micro-cracks in all kinds of the specimens. Furthermore,
it has been found that notch sensitivity of austenitic stainless steels is higher than that of a typical
plain carbon steels under the higher stress concentration factor region.
Identification of a Defect Using the Equivalent Load Method
Authors: Kisu Hiroyuki , Rong Gui Ming
Published: March 2009

This paper will propose an identification algorithm for a small defect in the case of the
bending problem of a beam. That is to say, the part where a defect exists is replaced by an
equivalent load term. It shows that the defect can be accurately identified even there is observation
error if the problem of identifying a defect is converted to that of identifying a load.
The Inhibition Effect of Imidazoline and Diethylene Triamine on the Stress Corrosion Cracking of 08Cr2AlMo Steel in H2S Solution
Authors: Zhang Yao Feng , Gu Bo Qin
Published: March 2009

08Cr2AlMo steel is a type of material developed especially for heat exchanger pipe
bundle used under H2S condition in the recent years. In this paper, some researches were carried out
on the stress corrosion cracking (SCC) susceptivity of 08Cr2AlMo steel in H2S water solution and
the inhibition of imidazoline and diethylene triamine on the SCC by means of slow strain rate
tensile test, scanning electron microscopy, potentiodynamic polarization and electrochemical
impedance spectroscopy (EIS). The results indicate that 08Cr2AlMo steel is highly susceptible to
SCC in saturated H2S solution for the fracture surfaces of specimen show typical quasi-cleavage
fracture. The addition of both imidazoline and diethylene triamine into saturated H2S solution is
effective on inhibiting the SCC. The inhibitors can reduce the potential of the cathodic hydrogen
evolution, which prevents the penetration of hydrogen into the specimen effectively. Furthermore,
inhibitors accelerate the formation of the chemically bonded film on the steel surface. It is also
found that when the concentration of inhibitors is below 0.2%, there is no obvious inhibition effect
on SCC, and the inhibition effect of diethylene triamine is better than that of imidazoline.
Ductile Crack Propagation Characteristics in Thin Steel Tubes
Authors: Kayamori Yoichi , Hillmansen S. , Crofton P.S.J. , Smith Roderick A.
Published: March 2009

Static ductile crack propagation tests were conducted using two pressurised thin
carbon-manganese steel tube specimens, and the crack tip opening angle (CTOA) was measured using
digital images captured on specimen surface. The critical values of CTOA for static crack propagation
decreased with crack extension while propagating crack was short. After the crack grew up to the
distance of the tube specimen thickness, the critical CTOA exhibited nearly constant. These
tendencies were the same as those of referential data in the thin single edge notched tension (SENT)
specimens of the same tubes. Using the data of both tube specimens and SENT specimens, it was
noted that the higher crack velocities slightly reduced the constant CTOA. A global constraint factor
was calculated for each tube specimen, and the constant CTOA decreased with the increase of the
global constraint factor. In addition, a dynamic ductile crack propagation test of a tube specimen was
carried out, and a crack velocity was measured. The estimation of the constant CTOA for dynamic
crack propagation in the tube specimen was performed by using the crack velocity.
Statistical Reconstruction of the One-Dimensional Mechanical and Fatigue Strengths
Authors: Zhao Yong Xiang , Yang Bing , Zhang Wei Hua
Published: March 2009

A Monte-Carlo simulation method for the reconstruction of one-dimensional probabilistic
mechanical and fatigue strengths is developed to realize reliability analysis at arbitrary probability and
confidence levels. This method is valid to the cases of the probabilistic parameters given at special
probabilities (Ps) or probability-confidences (P-Cs). To overcome the shortage of common
simulations with numerous samples which is out of true production practice, a simulation policy is
newly suggested with 7 to 20 samples for material small specimens and, at most 10 for structural
specimens and 5 percentages for the error of simulated parameters fitting the original ones. Details of
the method in practice are studied for the six possible statistical distributions i.e. normal, lognormal,
three-parameter Weibull, two-parameter Weibull, maximum value, and minimum value ones. The
reconstructions of the fatigue limits of 10 Chinese engineering materials have indicated the
availability and feasibility of the present method.
Reliability Analysis of Railway Tunnel Construction Process within Soft and Weak Rock Mass Using the Unified Elasto-Plastic Strength Criterion
Authors: Lian Jun Ying , Zhou Tai Quan , Hua Yuan , Dai Guo Liang
Published: March 2009

Variability in the physical properties of rock mass is a major source of uncertainty
encountered in railway tunnel stability analysis. The conventional safety factor method on stability
assessment of railway tunnel within soft and weak rock mass can not represent the variability of
rock mass. A formulation to compute the reliability of soft and weak rock mass, in which physical
non-linearity is taken into account, is proposed. To consider the intermediate principal stress effect
on the rock mass strength, the unified elasto-plastic strength criterion is proposed in the nonlinear
finite element analysis. The unified rock mass elasto-plastic material model is implemented in
ABAQUS user interface. The reliability analysis is performed in two steps. Firstly, the failure
response is obtained by fitting the limit state function of the rock mass using the quadratic
polynomial based on the nonlinear finite element analysis of the rock mass. Secondly, the JC
method is proposed to obtain the design point and the reliability index of rock mass. As a case for
study, the reliability analysis of Jinhuashan railway tunnel within soft and weak rock mass is
studied using the proposed method. The two dimensional analysis is performed to consider the
excavation stage effect and the unloading effect on the rock mass. Computation result shows that
the rock mass is in stability.
Comparison of Reliability of Solder Joints by FORM and SORM
Authors: Lee Ouk Sub , Hur Man Jae , Park Yeon Chang , Kim Dong Hyeok
Published: March 2009

The difference in the Coefficient of Thermal Expansion (CTE) between the chip and the
substrate generate thermal displacement in the solder joint. It seems to be a main cause of failure in
the solder joint when the chip and the substrate are heated repeatedly. The failure of the solder
joints by thermal fatigue is known to be influenced by varying boundary conditions such as the
difference in CTE, the height of solder, the Distance of the solder joint from the Neutral Point
(DNP) and the temperature variation. In this paper, the effects of varying boundary conditions on
the failure probability of the solder joint are studied by using the probabilistic approach methods
such as the First Order Reliability Method (FORM) and the Second Order Reliability Method
(SORM).
Safety Evaluation of Pressure Piping with Weld Flaw after Long Time Service in a Water Power Plant
Authors: Zheng San Long , Gao Zeng Liang , Chen Nian Jin , Zhuang Li Jian , Ye Yu Feng , Yu Xue Feng
Published: March 2009

Pressure steel pipings in a water power plant have been in service for over fifty years. In
order to assess the safety of the piping, whole check and tests for the piping were carried out. The
material for some piping is ST3 from former USSR, the other is A3 made in China. The mechanical
properties were investigated by tests and were compared with the original material properties. The
result shows the yield strength and tensile strength of serviced steels are less than those of original
materials. The surfaces of the piping were checked to investigate the corrosion, surface defects. The
flaws in the welds and near the welds of the pipings were detected by UT and MT, and several weld
flaws were found. Based on the test and NDT investigation results, the strength, fracture and fatigue
life of the pipings are assessed according to Chinese standard GB/T19624-2004 and British standard
BS7910-2000. The assessment results show that the strength of the piping is enough, and the pipings
with these flaws does not fracture. The piping can be safe in service under the normal operating
condition for 104 to 106 cycles.
Research on Crack Measurement Technique in Solids Material with Digital Image Correlation (DIC)
Authors: Zhu Jian Xin , Gao Zeng Liang
Published: March 2009

The measurement of crack propagation in solids is of vital importance for the research of
the fatigue characteristic of solid materials. By analysis of the image based measurement technique,
a contact-free crack measurement approach was proposed based on image cross correlation
algorithm. Experiment was performed to verify the validity of this method and it was found that the
method is of high precision. The approach distinguished itself from traditional methods by several
characteristics: it has relatively high measuring accuracy, the crack propagation can be continuously
measured with this method, the amount of information that the approach provide is much more
abundant than that of other methods. The method is proved to be an efficient method for crack
measurement and can be applied in fatigue induced material cracking researches.
Study on Reliability Analysis of Tailings Dam Stability
Authors: Zhang Chao , Yang Chun He , Chen Feng
Published: March 2009

Since the construction method of tailings dams determines the uneven distribution of
tailings, a reliability theory is introduced to analyze the stability of tailings dams. Based on the limit
equilibrium method and reliability theory, the sensitivity and reliability of a typical tailings dam are
analyzed. Reliability analyses with different types of the variable probability distribution types
show that the effect of the probability distribution type on reliability analysis can almost be ignored.
Besides, the sensitivity analyses of different variables show that the strength indexes and density of
tailings will affect the analysis results of stability reliability. Therefore the strength indexes c, φ
and density ρ must be considered as basic variables to analyze the stability reliability of tailings
dams.
Influence of Tapered Cross Section on Fatigue Damage of Cladding Fasteners on Side Faces of Tall Buildings
Authors: Kim Young Moon , Ko Nag Ho , Yang Cheol Min , You Ki Pyo
Published: March 2009

An appropriate choice of building shape and architectural modifications can result in the
reduction of motion by altering the flow pattern around a building. Tapering which is one of
aerodynamic devices has been known to be effective to reduce acrosswind response [1, 2]. The
exterior wind loading patterns on claddings are sensitive to the building shape. When a building has
a tapered cross section along the height, the influence of the exterior wind loading patterns on the
wind-induced high-cycle fatigue damage of the cladding fastener of the tapered building needs to be
found. In this study, the fatigue damage of the cladding fastener of a non-tapered building and two
tapered buildings is estimated by using the rainflow cycle counting method and Miner’s rule. The
fatigue damage is compared with one another in order to investigate the influence of the tapered
cross section on the fatigue damage of cladding fasteners on side faces of tall buildings
Nonlinear Response of Clamped Circular Plates Subjected to Transverse Excitation Load
Authors: Zhao Yong Gang , Zhao Wei Dong , Li Shi Rong , Ma Lian Sheng
Published: March 2009

Based on the von Kármán classical nonlinear plate theory, nonlinear axisymmetric
vibrations of a clamped thin circular plate subjected to transverse harmonic load are investigated.
Effects of static deformation on the vibration responses are considered. Harmonic motion is assumed.
The time variable is eliminated and the partial differential equations are converted into a system of
nonlinear ordinary differential equations by employing a Kantorovich time averaging method. The
resulting nonlinear ordinary differential boundary-value problem is solved numerically by using
shooting method. Effects of static-dynamic load on the transverse deflection, frequencies and
amplitudes are examined in details. The resonance phenomenon is discussed emphatically.
Wetting Effects of Rockfill on the Deformation of the Yellow River Xiaolangdi Dam
Authors: Chen Li Hong , Zhou Xiao Guang , Wei Yin Qi
Published: March 2009

The deformation and strength characteristic of rockfill is different when it is dry or wet.
The wetting effects should be a major factor in the long-term settlement of a rockfill dam. The 160 m
high Yellow River Xiaolangdi dam is a rockfill dam with inclined core clay. Moistening laboratory
tests were carried out to investigate the deformation and strength characteristic of the rockfill in the
Xiaolangdi dam. Based on the test results, two-dimensional consolidation numerical simulations on
the dam employed nonlinear stress strain constitutive model were conducted to investigate the effects
of wetting on the deformation performance of the dam.
Application of Distance Evaluation and its Improved Algorithms in Engineering Materials Selection
Authors: Zhang T.Y. , Yang Rui Chen
Published: March 2009

Distance evaluation and its improved algorithms using Vertical distance instead of
Euclidean distance were discussed in engineering materials selection. Taking the selection of
materials for low temperature storage container as an example, based on eight kinds of evaluation
indices, according to the weight obtained by AHP method, ten kinds of candidate materials were
evaluated by using distance evaluation and its improved algorithms. The results indicate that, the
optimal material selected coincides with the practice of industry, and the sequence of the candidate
materials arranged using improved algorithms is more reliable, which shows that improved
algorithms of distance evaluation is a feasible and effective way for engineering materials selection.
The Microstructures and Catalysis of Metallic Films Covering Diamond Single Crystals Synthesized from Fe-Ni-C System
Authors: Wang Mei , Li Mu Sen , Yin Long Wei , Qi Yong Xin , Xu Bin , Gong Jian Hong
Published: March 2009

The metallic films covering diamond play a very important role in the course of diamond
nucleation and growth from Fe-Ni-C system at high-temperature and high-pressure (HTHP). The
microstructures and surface morphologies of the metallic films are investigated by field-emission
scanning electron microscope (FESEM) in this paper. It is shown that there are large numbers of
small particles and a series of serrations on the inner surface of the films. It is calculated that the
metallic film is mainly composed of (Fe, Ni) 3C, (Fe, Ni)2 3C6, but no diamond structure. The results
by energy dispersive spectrometer (EDS) analysis are in good agreement with these by transmission
electron microscopy (TEM). It can be concluded that the carbon atom groups coming from the
decomposition of Fe-C compound rich in carbon in the film are deposited on the diamond surface
directly and diamonds grow in the model of sandwich.
Design of a Novel Micromachined Gyroscope with Compensatory Capacitance
Authors: Chen Wei Ping , Chen Hong , Han Tian , Liu Xiao Wei , Wang Hong Yu
Published: March 2009

This paper presents a novel bulk micromachined gyroscope with the compensatory
capacitance. Independent driving and sensing beams and a dual-frame structure are adopted to
decouple mechanically for stable operation. The method of electrostatic push-pull drive and
capacitive sense combs based on the slide film damping are applied to obtain a large driving force and
high quality factors. The compensatory capacitance is designed to compensate the deviations of
sensing differential capacitance from fabrications. The designed gyroscope has matched resonant
frequencies of 2187Hz and 2206Hz for the drive and sense modes, respectively. Considering the noise
of interface circuits, the gyroscope system sensitivity can reach 14.2mv/o/s, theoretically.
Effects of Phase-Equilibrium Temperature and Pressure on the Thickness Decision of a Methane Hydrate Container
Authors: Lee Jae Hoon , Kim Hyo , Choi Song Chun
Published: March 2009

The thickness of the process equipment increases in proportion to pressure for the methane
hydrate transportation and storage. The pressure is one of the most important factors, because a
material must be selected in the way of proper pressure and temperature to design the process
equipment. Therefore, we tried to figure out whether the phase equilibrium temperature & pressure
can be applied to the designed temperature and pressure or not, and carried out the thickness
calculation of the pure methane hydrate container in accordance with “Boiler and Pressure Vessel
Code - Division I of Section VIII, ASME”. Also, we studied on the effect of the container’s thickness
using the results of the phase equilibrium temperature and pressure measurement including the
inhibitor and promoter of the methane hydrate on some related references.
Fatigue Design of the Railroad Car Body Member Using a Simulated Single Spot Welded Joint
Authors: Bae Dong Ho , Lee Sol Bin , Park Sun Kyu
Published: March 2009

In order to develop a fatigue design method for the actual railroad car body structures
using the fatigue data on simulated single spot welded lap joints, firstly, evaluated fatigue strength
on the spot welded t-type member which is a component of the actual railroad car body structure.
And next, possibility of fatigue design for spot welded T-type member using the fatigue data of
single spot welded lap joints was investigated. From the results, it was found that, even though there
is some difference in fatigue strength between single spot welded joint and the actual members
under the same fatigue life, the fatigue design criterion could be predicted by correction between
them.
Structural Stability Evaluation for Lifting Lug Design of Large Marine Engine by Finite Element Analysis
Authors: Lee W.C. , Kim Chae Sil , Na J.B. , Lee D.H. , Cho S.Y. , Choi H.O. , Song Jung Il
Published: March 2009

Since most marine engines are generally very huge and heavy, it is required to keep
safety from accidents in dealing them. Several types of lifting lugs have been used to assemble
hundred ton–large steel structures and carry the assembled engines. Recently a few crashes have
been occurred in carrying engines due to breaking down the lugs. Although the stability evaluation
of the lifting lug has therefore been very important for safety, systematic design procedure of the
lugs, which includes the structural analysis considering stability, has few reported. This paper
describes the three dimensional finite element structural modeling for a lifting lug, the studies for
determining the reasonable loading and boundary conditions, and the stability evaluation with the
results of structural analyses. It should be very helpful for designing the other types of lifting lugs
with safety.
Microstructure and Mechanical Properties of High Densification Mo/Cu Composites
Authors: Chen Guo Qin , Wu Gaohui , Jiang Long Tao , Zhu De Zhi , Sun Dong Li
Published: March 2009

Microstructure and mechanical properties of the 55%, 60% and 67% Mo/Cu composites
for electronic packaging application fabricated by a patent squeeze casting route have been
investigated. The results show that Mo particles are homogeneously distributed in the matrix, and the
Mo-Cu interfaces are clean, free from interfacial reaction products and amorphous layers. The
densification of the Mo/Cu composites is higher than 99%. The as-received composites exhibit a
Brinell hardness varying from HB178.1 to HB196.9 and an elastic modulus varying from 177GPa to
213 GPa. The tensile strength of the composites is higher than 480MPa. Moreover, the composites
display favorable plasticity, while the elongation of the 55% Mo/Cu composite is as high as 5%.
Obtaining high tensile strength and elongation in the composite is attributed to the high densification,
as well as the clean and smooth Mo-Cu interfaces, both resulting from the cost-effective
squeeze-casting technology.
Thermal Stress Distribution in the Corner of IC Package Structure
Authors: Li Hong Peng , Shi Rong , He Yu Ting , Zhang Heng Xi , Li Feng
Published: March 2009

Passivation cracking is one of the main failures of Integrated circuits (ICs). A major cause
for these failures is due to the mismatch of Coefficients of Thermal Expansion (CTE), Young’s
modulus, Poisson’s ratios of package materials. In this paper, in order to analysis the stress
distribution around the passivation layer corner, the finite element simulations and simplified
analytical solutions are both applied. Then the comparison of stress values is made between the FEM
result and simplified analytical solution, which shows that there is a good agreement. Based on these
analyses, a conclusion can be drawn out that the simplified analytical model can be used to analyze the
maximum stress around the passivation layer corner fast when design a chip preliminarily.
Effect of Extrusion Ratio on Fatigue Properties of Hot-Extruded Magnesium Alloys
Authors: Ishihara Sotomi , Shibata H. , Komano K. , Goshima Takahito , Nan Z.Y.
Published: March 2009

In the present study, fatigue experiments were conducted using two kinds of extruded
magnesium alloys with different extrusion ratios. Effect of the extrusion ratio on fatigue lives and
crack propagation behavior was studied in detail. There was no dramatic effect of the extrusion ratio
on fatigue life, fatigue limit and crack propagation behavior.
Research on Creep Properties of Sn2.5Ag0.7CuXRE Lead-Free Soldered Joints for Surface Mount Technology
Authors: Zhang Ke Ke , Wang Yao Li , Fan Yan Li , Yiang Jie , Yan Yan Fu , Zhang Xin
Published: March 2009

Creep property of solder alloys is one of the important factors to effect the reliability of
surface mount technology (SMT) soldered joints. The creep behavior and its rupture life of
Sn2.5Ag0.7CuXRE lead-free soldered joints were separately investigated and predicted under
constant temperature by a single shear lap creep specimen with a 1mm2 cross sectional area and
finite element method (FEM) in this paper. Results show that the creep property of
Sn2.5Ag0.7Cu0.1RE is superior to that of the commercial employed lead-free solder Sn3.8Ag0.7Cu
and the creep rupture life of its soldered joints is 8.4 times more than that of Sn2.5Ag0.7Cu solder.
The creep rupture life of Sn2.5Ag0.7CuXRE lead-free soldered joints indirectly predicted by FEM
is better in accord with that of actual testing results, which are important to design the reliability of
lead-free soldered joints for SMT.
In Situ Thermal-Mechanical Fatigue Testing of Thin Au Lines
Authors: Zhang G.P. , Zhang Bin , Yu Q.Y. , Tan J.
Published: March 2009

An in-situ testing system for thermal-mechanical fatigue of thin metal lines was setup
inside a dual-beam focused ion beam (FIB)/scanning electron microscope (SEM) system. Alternating
currents (AC) were applied to narrow Au lines 200-nm-thick through nanomanipulator needles.
Preliminary results show that severe thermal-mechanical fatigue damage can be generated by the
action of the applied AC. The in-situ recording of the evolution of the damage has been carried out
and the possible mechanism of the thermal-mechanical fatigue damage in the Au lines resulted from
the joule heating was discussed.
Theoretical Analysis of Young’s Modulus and Dielectric Constant for Low-k Porous Silicon Dioxide Films
Authors: Li Ke Jia , Xiao Xia , Jin Yu Feng
Published: March 2009

Porous silicon dioxide films featuring low dielectric constant are of great scientific and
commercial interest because of their outstanding potential for application to microelectronic
interconnect. However, some reliability problems arise in porous SiO2 films due to their poor
mechanical performance. Therefore, it is very important to understand the mechanical and electrical
properties of porous SiO2 films. New 2-D models with circle pores and 3-D models with cubic
pores are proposed in this work. Simulated results of porous SiO2 structures in the case of periodic
and random arrangement, which are implemented through ANSYS, are also provided. Critical
parameters such as Young’s modulus E and dielectric constant k of porous films are investigated.
Calculation results show that dielectric constant reaches as low as 2.5 when porosity of films is
about 40%, while E keeps over 3 GPa if porosity remains in the range from 30% to 40%.
The Analysis to the Correlation between Cooling Medium and Cooling Result of DWTT Specimen
Authors: Chen Hong Da , Feng Y.R. , Huo Chun Yong , Tian Tao , Li Yang , Dong Bang Sheng , He Xiao Dong , Wang Chen , Li Jin Feng , Zhu Li Xia
Published: March 2009

The cooling medium choice is restricted due to no detailed regulations for temperature
control as the specimen with gaseous cooling medium in the API, ASTM and the standards or
specifications of China. The analysis and calculating are made to the physical process of the
cooling. The preservation hold time are provided for DWTT specimen at different temperature in
the gaseous cooling medium. It provide primary sustaining base to control the cooling process of
gaseous cooling medium. The essential point of the precise means of temperature testing is brought
forward at the same time.
Exact Relationships between Eigenvalues of FGM Circular Plates Based on RPT and those of Isotropic Homogeneous Circular Plates Based on CPT
Authors: Ma Lian Sheng , Wu Lei
Published: March 2009

Based on the mathematical similarity of the eigenvalue problem of the Reddy’s third-order
plate theory (RPT) and the classical plate theory (CPT), relationships between the solutions of
axisymmetric vibration or buckling of functionally graded material (FGM) circular plates based on
RPT and those of isotropic homogeneous circular plates based on CPT are presented, from which one
can easily obtain the RPT solutions of axisymmetric vibration or buckling of FGM circular plates
expressed in terms of the well-known CPT solutions of isotropic circular plates without much tedious
mathematics. Effects of rotary inertia are not considered in the present analysis. The relationships
obtained from the present analysis may be used to check the validity, convergence and accuracy of
numerical results of FGM plates based on RPT, and also show clearly the intrinsic features of the
effect of transverse shear deformation on the classical solutions.
Study on the Electrochemical Behavior of the Weldment for SPV50Q Steel in H2S-Containing Environment
Authors: Tang Jian Qun , Gong Jian Ming , Tu Shan Tung , Jiang Yong
Published: March 2009

The difference in microstructures of the base metal (BM), weld metal (WM) and
heat-affected zone (HAZ) in the weldment is one of the major reasons for the failure of the welded
equipments, which can be essentially attributed to the non-homogeneous corrosion occurred
electrochemically on the weldment. Therefore, it is necessary to explore the corrosion properties of
weldment. In this paper, the electrochemical behavior of SPV50Q steel weldment was investigated.
The polarization curves of BM, WM and HAZ in 5wt.%NaCl-0.5wt.%HAc solution containing H2S
were measured by potentiodynamic polarization. Interface characterization was also conducted by
electrochemical impedance spectroscopy (EIS). The results show the anodic curves are almost same
regardless of various pH or H2S content, but the cathodic curves show some difference. Relatively
large variation in corrosion current density (icorr) obtained by fitting technique exists among BM,
WM and HAZ. icorr of WM and HAZ is larger than that of BM, and icorr of WM is maximum.
According to EIS results, polarization resistance (Rp) increases in the orders of WM, HAZ and BM.
It is concluded that WM and HAZ are less resistant to corrosion than BM, which can be correlated
to the premature failure of the weldment serviced in H2S-containing environment such as sulfide
stress corrosion cracking (SSCC) and /or stress oriented hydrogen-induced cracking (SOHIC) etc.
Evaluation of Stress Corrosion Cracking of Type 304L Stainless Steel in Low Concentration Sodium Hydroxide Solution with High Temperature
Authors: Zhou Rong Rong , Gong Jian Ming , Li Feng , Tu Shan Tung
Published: March 2009

Stress corrosion cracking (SCC) of austenitic stainless steel serviced in aggressive
environment often occurs in power, petrochemical industry, and leads to premature equipment
failure and great economic loss. This paper focuses on the problem of the SCC on the 304L stainless
steel nozzle of a hydrogenation reactor, which is caused due to on-line alkali cleaning.
Susceptibility for SCC was evaluated by Slow Strain Rate Test (SSRT) for as-rolled and sensitized
304L stainless steel in low concentration sodium hydroxide solution with high temperature. The
effects of different strain rates, different concentration of sodium hydroxide and different solution
temperatures on SCC were investigated. On the basis of this, the contrast tests were also performed
in high temperature pure water. After SSRT, fractograph of the fractured specimens was analyzed
by using scanning electron microscopy (SEM).
Application of Superelasticity of SMAs in Bolted End-Plate Connection
Authors: Ma Hong Wei , Cho Chong Du
Published: March 2009

Superelastic shape memory alloys (SMAs) can experience large strains up to 8~10% and
restore residual strains just by removing the stress. By employing this unique characteristic of SMAs,
a new beam-to-column connection is presented in this paper. The proposed SMA connection consists
of an extended end-plate, eight long shank Nitinol SMA bolts, beam flange ribs, beam web stiffeners
and continuity steel plates for reinforcing column flanges. In order to predict the behavior of SMA
connection, 3-D solid finite element models are set up in ANSYS. The numerical results indicate that
the local buckling of beam is avoided and a plastic hinge forms at beam-to-column interface when the
moment-carrying capacity of bolt cluster is below the elastic flexural capacity of connecting beam.
The SMA connection shows stable moment-rotation hysteresis curves with re-centering capability,
which demonstrates the connection’s self-healing deformations function. Far different from energy
dissipated by steel yield in traditional connection, the SMA connection shows moderate energy
dissipation capacity, and this amount of energy is mainly dissipated by the superelastic behavior of
SMA bolts. Moreover, the connection model shows a large inelastic rotation capacity beyond 0.03 rad.
The ductility of SMA connection is deeply influenced by the length of SMA bolts, and the 2.2 times
length of normal bolt is suggested for SMA bolts.
Crystal Structure of the New Compound NdFeSb3
Authors: Qin Ping Li , Nong Liang Qin , Zhang Ji Liang , Qin Hai Qing , Liao Jiang Ping , Zeng Ling Min
Published: March 2009

The crystal structure of a new compound NdFeSb3 has been determined by X-ray powder
diffraction using the Rietveld method. The compound crystallizes in the orthorhombic, space group
Pbcm (No.57) with the CeNiSb3 structure type and lattice parameters a=1.26828(2)nm,
b=0.61666(2)nm, c=1.81867(4) nm, z=12 and Dcalc=7.917g/cm3.
Polyimide-Epoxy Blend for Binding Silicon Steel Sheets of Aerospace Electrical Machineries
Authors: Zhou Jian Fang , Li An , Huang Hong Chi , Rao Bao Lin
Published: March 2009

A polyimide-epoxy blend has been prepared by reacting epoxy resin with imide
compounds containing carboxyl groups at the ends of the molecular. When coated on the silicon steel
sheets, the blend can be used as a kind of adhesive to bind together the silicon steel sheets of
aerospace electrical machineries. Put pressure of 0.4-0.5MPa on a stack of coated silicon steel sheets,
and cured at 200°C for 2 hours, binding course of 0.01- 0.02mm on the sheets was formed. Tensile
shear strength of the binding course on stainless steal substrate is greater than 23MPa at room
temperature, 8MPa at 200°C. After enduring in air at 300°C for 48 hours the tensile shear strength at
room temperature remained 17MPa, dipping in aerospace lubricant at 250°C for 48 hours remained
18 MPa, steeping in dimathylacetamide at 160°C for 12 hours remained 12 MPa.
Investigations on Hydrogen Content Change in Melt Aluminum during Casting under Adjusted Pressure
Authors: Xu Zheng Bin , Zou Yong Zhi , Gu Hong , Zeng Jian Min
Published: March 2009

In this paper, a new low-pressure die-casting with degassing function, casting under
adjusted pressure (CAP), is proposed. The working principle of CAP process is introduced in details.
This paper focuses on the influences of moisture of compressed air on the hydrogen content within the
melt aluminum during the cyclic vacuum-pressurizing programs for CAP process. The experimental
results indicate that degassing under vacuum acts positive in refining aluminum melt. The relative
moisture of compressed air exerts a significant influence on the hydrogen content of aluminum melt.
After the melt aluminum is exposed to the air with a relative moisture of 85% for 90 min, the
hydrogen content of the melt aluminum can get to 0.4 ml/100g/Al; while under the circumstance of
CAP process, the hydrogen content is maintained between 0.05 and 0.15 ml/100g/Al depending on
the moisture capacity of the air, which virtually has no more influence on the casting qualities. Under
the condition of dry compressed air, the hydrogen content can be kept at a level as low as
0.05ml/100g/Al, which facilitates to obtain high air-tightness castings.
Experimental Analysis of Chemical Damage of Water to Soil Structure
Authors: Zhang Xin Gui , Ma Guo Wei , Yi N.P. , Chen X.L. , Wu H.
Published: March 2009

Chemical components of the soil take an important role in the structure stability. It controls
the soil structure under the normal water environment such as ordinary temperature, atmospheric
pressure, and slowly changing hydro-chemical environment etc. It also has an important influence on
the ground subsidence and the formation of soil caves as well as the collapse of dispersive soil.
Scanning Electron Microscopy(SEM), CT technology and X diffraction were used to measure the
chemical damage of water to the soil structure in the laboratory. Results indicate that under normal
water environment, the change of the environmental parameters is not sufficient to cause damage to
the internal crystal force of mineral intergranulars and to activate atoms in crystal lattice, which leads
some defects and displacement of the crystal lattice. However, it can activate linking substance of
clay grains be defined as “soil mini-structure”. As the greatest contributor of soil stability, the
mini-structure is the "platform" and main place in which soil stability and instability will develop.
The Carbonyl Group Measurement of the Membrane Copolymerized by Low-Temperature Plasma at Atmospheric Pressure of C2H2 and CO2
Authors: Hong Kwang Joon , Chun Young Nam , Lee Bong Ju
Published: March 2009

We developed a device that makes possible the normal production of low-temperature
plasma under atmospheric pressure. For plasma generation, a radio frequency of rf (13.56MHz) was
used. From the Fourier transform infrared (FT-IR) analysis, the absorption peak of C=O (the carbonyl
group) was observed around 1715 cm-1, and the absorption peak of CH was observed around 2950
cm-1. Of those, from the conclusion that the absorption peak of C=O was proportional to the amount
of CO2 added, we discovered that the C=O carbonyl group originated from the CO2 molecules.
Investigation of Mechanical Stability of Thermally Aged a-c:H DLC Films with Different Precursor Gases
Authors: Baek Seung , Parks Se June , Lee Kwang Real , Seok Chang Sung
Published: March 2009

A-C: H (Hydrogenated amorphous carbon) diamond like carbon(DLC) film is the low
stabilities of chemical and mechanical properties at high temperatures. Some researchers reported that
Raman spectra shown significant conversion of DLC films to nano-crystalline graphite on heating in
ambient air at temperatures above 300°C and conversion to nano-crystalline graphite was completed
by 450~600°C In this study, DLC films(thickness : 1.5-m) were deposited on p-type (100) silicon
films by using C6H6 and C6H14 plasma produced with a 13.6MHz RF source. To investigate the
mechanical stability of DLC films below 250°C, we thermally aged the films for different aging
temperatures (150°C, 200°C, 250°C) and times (0: virgin, 120, 240, 360 hours). By using indentation
test and Raman spectra analyses, it has been found that the H3/E2 decreases with increasing I(D)/I(G)
ratio. Also we confirmed that sample-2(precursor gas: C6H14) had better mechanical characteristic and
thermal stability than the sample-1(precursor gas: C6H6).
The Method to Determine the Expression for Fatigue Curves
Authors: Yi Hong Liang , Ma Ming Tu , Li Zhi Gang , Zhang Hao
Published: March 2009

There are three common empirical expressions used for the fatigue curves, which are
power function, exponential function and three-parameter power function expression, respectively.
The mathematical difference between the former two and the latter is whether there exists the constant
term S0 in the equations. The S0 can be calculated to determine whether the two-paprameter
expression or three-parameter expression should be used. If the two-parameter expression should be
used, the power function and exponential function expressions can be compared to determine which
one is the optimum one. Finally, the method has been validated by several groups of fatigue data.
Separation of Primary Stress in Finite Element Analysis of Pressure Vessel with the Principle of Superposition
Authors: Gao Bing Jun , Shi Xiao Ping , Liu Hong Yan , Li Jin Hong
Published: March 2009

A key problem in engineering application of “design by analysis” approach is how to
decompose a total stress field obtained by the finite element analysis into different stress categories
defined in the ASME Code III and VIII-2. In this paper, we suggested an approach to separate primary
stress with the principle of superposition, in which the structure does not need to be cut into primary
structure but analyzed as a whole only with decomposed load. Taking pressurized cylindrical vessel
with plate head as example, the approach is demonstrated and discussed in detail. The allowable load
determined by the supposed method is a little conservative than that determined by limited load
analysis.
Stress Distribution of the Composites Reinforced by Slub-Like Short Fibers
Authors: Dong Li Xin , Dai Guang Ze , Zhou Xian Feng , Liu L.L. , Ni Qing Qing
Published: March 2009

The model of slub-like short fibers reinforced composites is suggested from the
viewpoint of bamboo in the nature and patterns characteristic of simulated silk PET used in textile
industry. The stress distributions in the enlarged-end fiber and in the matrix are analyzed. The axial
stress in the fiber and matrix is found to increase and the interfacial shear stress decrease with the
radius of the enlarged end.
Research on Physical Significance of the Larson-Miller Parameter and its Electron Theory for Heat-Resistant Steels
Authors: Yang Rui Chen , Li Z. , Chen Kui
Published: March 2009

The Larson-Miller parameter (LMP=T(C+log t)) with the determined C-value is
suitable to describe the high-temperature ageing behaviour of pearlitic heat resistant steels, such
as 12Cr1MoV with C of 20.62, and 15CrMo 20.30. The heat strength parameter Pc was proposed
as one property of materials, and heat processing factor P as temperature-time processing
parameter. In addition, the relationship between Pc and P was discussed. Then, based on the
calculation of valence electron structures by the Empirical Electron Theory of Solid and
Molecules (EET), the physical nature and microscopic meaning of C constant in LMP were
analyzed, including the effects of carbon content on C-value.
Microstructure and Strength of Oxidation-Bonded Porous Silicon Nitride Ceramics
Authors: Ding Shu Qiang , Zeng Yu Ping , Jiang Dong Liang
Published: March 2009

An oxidation bonding process was developed to fabricate oxidation-bonded porous
silicon nitride (Si3N4) ceramics from α-Si3N4 powder in air at 1100-1400oC. Si3N4 particles are
bonded by the oxidation-derived silica (SiO2) and the pores derive from the stack of Si3N4 particles
and the release of N2 and SiO gas during the sintering. The microstructure of oxidation-bonded
porous Si3N4 ceramics was observed. Moreover, the fracture mechanism was analyzed. Effects of
the bonding phases and pores on the flexural strength were investigated. Oxidation-bonded porous
Si3N4 ceramics with high flexural strength was obtained by restraining the crystallization of
amorphous silica and forming the well-developed necks between Si3N4 particles.