bluuebunny/crossref_metadata_2025 huggingface dataset:
Reliability Prediction for 95.5Sn3.9Ag0.6Cu Solder Bump and Thermal Design for Lead Free System in Package with Polymer-Based Material
Authors: Hsu Hsiang Chen , Hung Wei Mao
Published: March 2009

This paper demonstrates the thermal-induced mechanical problems resulted from various temperature profiles of reliability test for a system-in-package (SIP) assembly process. The package includes two flip chip mounted chips (underfilled), two memory CSPs, some passive SMDs and 4-layer BT substrate. The flip-chip specimen was taken and the Moiré Interferometry was used as
methodology to verify the developed Finite Element Model and material property. It also shows that the developed finite element model is capable to simulate the JEDEC standard JESD22-A104 reliability thermal cycle test and then to predict solder fatigue life and to summarize design rules for thermal optimization of package based on the creep model and viscoplastic model of solder while the
SIP package design is proceeded. Thermal design for SIP depends on the placement of FC chip (high power) and memory CSP components. Passive SMDs are also included to study the effect of thermal-induced stress. A series of comprehensive parametric studies were conducted in this paper.
An Experimental Study on the Effects of Abrasive Particle Sizes on Polishing Phenomena
Authors: Jeng Yeau Ren , Huang Pay Yau
Published: March 2009

The effects of abrasive particle size on polishing phenomena during wafer planarization are investigated using a high precision polishing process test bench with in-situ measurement technology. The present experimental results are found to be comported with the experimental and theoretical data published previously. The current experimental outcomes can help to understand the polishing mechanism and develop the relating theoretical model.
A Monte Carlo Model for Analyzing the Effects on Radiometric Temperature Measurement in Rapid Thermal Processor
Authors: Tsao Jen Chieh , Su Chiung Chieh
Published: March 2009

The radiometric temperature measurement is often applied to the in-situ and real-time
monitor for rapid thermal processing of semiconductor wafer. To obtain good accuracy, the effective emissivity of measured spot is determined simultaneously as well. However, the effective emissivity strongly depends on the characteristics of wafer, processing chamber, and sensors. This paper presents a Monte Carlo model with bi-directional reflection distribution function to estimate the related effective emissivity of wafer. The ends of radiation thermometer considered are located
either on the inner surface of processing chamber or at the proximity of wafer. The results are checked and compared with those of the previous work. Finally the primary effects on radiometric temperature measurement are analyzed and discussed.
Automatic Full-Field 3-D Profilometry Using White Light Confocal Microscopy with DMD-Based Fringe Projection
Authors: Chen Liang Chia , Kao Wei Chieh , Huang Yao Ting
Published: March 2009

A new full-field 3-D micro surface profilometer using digital micromirror device
(DMD)-based fringe projection strategy and confocal principle is presented in the article. In viewing the fact that conventional laser confocal measurement method not only easily encounters undesired irregular scattering problems, but also lack scanning efficiency due to its single-point type measurement, the newly developed automatic surface profilometer deploys a DMD chip to project spatially encoded digital fringe patterns with dynamic light intensity, onto the object to obtain
excellent measurement performance. A novel digital fringe pattern design with adaptive sinusoidal intensity modulation was developed for active fringe projection, to obtain optimized depth resolution with a micrometer lateral resolution in confocal measurement. Some of semiconductor components have been measured to attest the feasibility of the developed approach. The depth measurement
resolution can reach better than 0.1μm and the maximal measured error was verified to be less than less than 0.5 % of the measured step size.
Three-Body Microcontact Model of Rough Surfaces and Its Application on Polishing of Wafer
Authors: Horng Jeng Haur , Lee Jian Shing , Du D.C.
Published: March 2009

In this study, a three-body microcontact model for rough surfaces is proposed in order to understand the effects of particles between surfaces on contact characteristics and its application on polishing of wafer. Both transitional surface-to-surface and particle-to-surface two-body microcontact simulations can be obtained according to the simplification of this model. In the three-body contact situation, the curves of contact area ratio versus dimensionless load are located in
the range between two straight lines. The surface-to-surface two-body contact situation is the upper bound and the particle-to-surface two-body contact situation is the lower bound. As the value of D/σ increases, the contact situation will approach the pure particle-to- surface 2-body contact situation. The model also is used to study the wear mechanisms of the silicon wafer.
Research and Development on Control System of Multicoil Inside Solidification Combined Winding Machine
Authors: You Bo , Ding Liang , Xu Jia Zhong , Yu Zhen Zhong , Jia De Li
Published: March 2009

Multicoil inside solidification combined winding machine, which can wind, solidify inside and extract high-pressure glass reinforced plastic (GRP) tubes, combines three conventional working procedures. The machine tool has four spindles of two groups working coordinately, improving machining efficiency greatly. This paper presents the realization of its control system, including the hardware and software architecture of the winding, inside solidification and extraction subsystems,
and the mutual communication among them. Several key technologies such as the realization of openness, multicoil winding for heavy caliber tubes and remote control are also introduced.
Stiffness of HSK Tooling System in High Speed Machining
Authors: Wang Gui Cheng , Wang S.L. , Wu Wei Guo , Shen Chun Gen
Published: March 2009

The stiffness of the HSK tool system directly influences the efficiency and the quality of high-speed machining. Based on the mechanics of materials and finite element method, theoretical analysis and digital simulation are done with the stiffness of the HSK tool system. An equation to calculate the deformation angle of the HSK shank is proposed. The basic change law of the stiffness of the HSK tool system is shown and it offers theoretical base for properly applying the HSK tool
system to maximize benefit. It is important in theory and application area to develop new-style tool system with our own intellectual property.
Optimization for the Maximum Rectangular Block from an Arbitrary Closed Region Using GA
Authors: Tsai Jen Shen , Cheng Chi Cheng
Published: March 2009

Methods of standard genetic algorithm (SGA) and adaptive genetic algorithm (AGA) are employed to improve performance of global cutting for an arbitrary closed region. Normal conditions and special types of the closed region are also analyzed and discussed by the area map. It appears that the presented GA frameworks are superior to the blind search algorithm (BSA) and are
suitable for the special types of remaining closed space (RCS). By comparing three experimental results, it can be concluded that area efficiency and time reduction are trade-offs.
Development of a 3D Cutter Compensation Postprocessor System for Multi-Axis Machining
Authors: She Chen Hua , Chang Chun Cheng
Published: March 2009

The compensation of tool wear is the important topics for numerical control machining. The lower-hand controller has the basic G code function (G41/G42) to obtain the compensated cutter location for planar contour machining. However, the advanced controller with cutter compensation vector function should be employed in order to process the three dimensional compensated tool path.
The purpose of this paper is to establish the algorithm for calculating the 3D cutter compensation vector and develop a generalized postprocessor system to obtain the NC code. Through the verification by the solid cutting simulation software, it confirmed the effectiveness of the proposed algorithm.
193 Excimer Laser Machined Electromagnetic Optical Scanning Mirror for a Laser Projection Display
Authors: Lin Chien Hua , Hou Ti Kuang , Wen Dong Cherng
Published: March 2009

Electromagnetic optical scanning mirrors for both horizontal and vertical scanning of a Laser Projection Display have been proposed. Electromagnetic actuation is selected because of the millimeter-sized mirror. For low cost reason, the glass and PMMA films are respectively used as the main structure of horizontal and vertical scanning mirrors. A mathematical model considering the operation frequency of the Laser Projection Display has been derived to fast design the geometry of
the scanning mirror. In order to machine scanning mirrors with high quality geometry, the 193 nm excimer laser is used as the major machine tool. Different control circuits have been developed to control both horizontal and vertical scanning. The scanning frequencies, 4.15 kHz and 260 Hz respectively for horizontal and vertical scanning mirrors, have been measured by laser Doppler
vibrometer. Comparing to other optical scanners, 193 nm excimer laser machined optical scanning mirrors have advantages in low cost and easy to fabricate. In this paper, a Laser Projection Display consisting of the horizontal and vertical scanning mirrors has also been built to show the application potential. A 2-D single color image with resolution of 46 × 32 pixels, 4.15 kHz of horizontal scanning
frequency and 60Hz of regulated vertical scanning frequency has been demonstrated.
Development of Finite Element Analysis Scheme for Micro Forming Using Grain Element and Grain Boundary Element
Authors: Ku Tae Wan , Lee June Key , Kang Beom Soo
Published: March 2009

A numerical approach for forming simulation and manufacturing of micro part, based on the elastic and the rigid-plastic finite element methods by using grain element and grain boundary element, is proposed to simulate MEMS/micro-structural deformation behavior of material during micro forming. The idea is to present the polycrystalline material by an aggregate of so-called grain element that describes the plastic deformations of each individual grain in view of micro-structure. This grain element is connected by grain boundary element to account for shear deformation between
grains. The main objective in this study is to develop the reliable finite element model and scheme for micro forming simulation with very thin sheet. The reliability for micro forming analysis is described from the comparisons of the micro-structural deformation behavior between the conventional rigid-plastic finite element analysis and the FE analysis of the developed program with very thin sheet
material.
Nanometrology – Nanopositioning- and Nanomeasuring Machine with Integrated Nanopobes
Authors: Jäger Gerd , Hausotte T. , Manske E. , Büchner H.-J. , Mastylo R. , Dorozhovets N. , Füßl R. , Grünwald R.
Published: March 2009

The paper describes the operation of a high-precision wide scale three-dimensional nanopositioning and nanomeasuring machine (NPM-Machine) having a resolution of 0,1 nm over the positioning and measuring range of 25 mm x 25 mm x 5 mm. The NPM-Machine has been developed by the Technische Universität Ilmenau and manufactured by the SIOS Meßtechnik GmbH Ilmenau. The machines are operating successfully in several German and foreign research institutes including the
Physikalisch-Technische Bundesanstalt (PTB). The integration of several, optical and tactile probe systems and scanning force microscopes makes
the NPM-Machine suitable for various tasks, such as large-area scanning probe microscopy, mask and water inspection, circuit testing as well as measuring optical and mechanical precision work pieces such as micro lens arrays, concave lenses, mm-step height standards.
A Finite Element Analysis for the Forging Process of Hollow Spur Gear
Authors: Yang Tung Sheng , Hsu Yuan Chuan
Published: March 2009

The process of precision gear forging has been developed recently because of its
advantages of giving high production rates, improved strength and surface finish. For complete filling up, predicting the power requirement is an important feature of the forging process. To analyze the process of incremental forging of hollow spur gear forms from initially ring-type specimens, a series of simulations using the program DEFORM-3D was carried out. The results of current simulation
were compared with the experimental data those obtained by forging of hollow spur gear forms. In addition, the influences of the process parameters such as module, number of teeth, the ratio of the inner radius to the outer radius, friction factor and the height of the billet on the forging force is also examined.
Diamond Tip Cantilever for Micro/Nano Machining Based on AFM
Authors: Park Jeong Woo , Lee Deug Woo , Takano Noboru , Morita Noboru
Published: March 2009

Nano-scale fabrication of silicon substrate based on the use of atomic force microscopy (AFM) was demonstrated. A specially designed cantilever with diamond tip allows the formation of damaged layer on silicon substrate by a simple scratching process. A thin damaged layer forms in the substrate along scanning path of the tip. The damaged layer withstands against wet chemical etching
in aqueous KOH solution. Diamond tip acts as a patterning tool like mask film for lithography process. Hence these sequential processes, called tribo-nanolithography, TNL, can fabricate 2D or 3D micro structures in nanometer range. This study demonstrates the fabrication processes of the micro cantilever and diamond tip as a tool for TNL. The developed TNL tools show outstanding
machinability against single crystal silicon wafer. Hence, they are expected to have a possibility for industrial applications as a micro-to-nano machining tool.
The Characteristic of Abrasive Particle in Chemical – Mechanical Polishing
Authors: Tsai Hung Jung , Chang C.C. , Jeng Yeau Ren , Chen Sih Li
Published: March 2009

Chemical Mechanical Polishing (CMP) is the key technique for wafer global planarization. However, the characteristic of abrasive particle, including particle size and grain/grain collision elasticity, plays an important role in CMP process. This investigation analyzes the slurry flow between the wafer and pad using a grain flow model with partial hydrodynamic lubrication theory. This model predicts the film thickness and remove rate of the slurry flow under a variety of the CMP
parameters including load, rotation speed, pad roughness, grain/grain collision elasticity and grain size. The theoretical results compare well with the previous experiment data. This study elucidates the grain characteristics during CMP process. It also contributes to the understanding of abrasive particle
effects in the chemical mechanical polishing mechanism.
A Pulse DC Plasma Deposited Resistor Process
Authors: Wen Fuh Liang , Lo Yu Lin , Lin C.H. , Mou Shann Chyi
Published: March 2009

The pulse DC plasma system offers so highly instant power to generate extremely intense plasma density that its applications are widely extended. In this work, the development of pulse DC plasma processing is studied for the sheet resistors, and the manufacturing mechanism relative to the properties of copper particles deposited on plastic materials is discussed by using atomic force
microscopy and line-resistance measured technique.
The Analysis and Modeling for Nutation Drives with Double Circular-Arc Helical Bevel Gears
Authors: Gu Bing , Yao Li Gang , Wei Guo Wu , Cai Ying Jie , Dai Jian Sheng
Published: March 2009

Based on the nutation movement of a rotating coin on a table, the formulae for calculating the transmission ratio between two nutation gears is developed. The tooth profile with a double circular arc for helical bevel gears in nutation drives is proposed and then the meshing equation during the nutation process and the universal equation of the crown gear tooth surface with helical double
circular arc profiles are obtained based on the gear meshing theory. Further, the modeling for nutation drives with the proposed profile is carried out in a virtual working process.
Metallurgy in Space
Authors: Jarvis David John , Minster O.
Published: March 2009

Over the past five years, an application-oriented research strategy has been initiated by ESA to permit valuable microgravity research in a broad range of physical sciences. The main objective is to integrate ESA, national activities and industry into an overall European strategy, which will allow research to be performed aboard the International Space Station (ISS), as well as other microgravity platforms, like unmanned space capsules, sounding rockets and parabolic flights.
A key area of microgravity research is centred on metallurgy in space. The principal aims of this research field are (i) to investigate various physical phenomena during solidification processes and (ii) to determine the thermophysical properties of important liquid alloys. A number of metallurgical sub-topics have been identified in the ESA research programme, including the columnar-to-equiaxed transition during solidification; metastable and non-equilibrium solidification; multiphase multicomponent alloy solidification; eutectic, peritectic, monotectic and intermetallic alloy growth; fluid flow effects on mushy zone formation; and the measurement of thermophysical properties of liquid alloys. This review paper will therefore highlight the theoretical,
experimental and modelling efforts currently being undertaken in the ESA programme.
Producing a Heusler Alloy Single Crystal
Authors: Veres Zsolt , Roósz András
Published: March 2009

The Heusler alloy Cu2MnAl is a ferromagnetic compound that is in the form of a single crystal suitable for the simultaneous monochromatization and polarization of a neutron beam. Our purpose is to produce such a monochromator. Pre-cast polycrystalline samples were resolidified in crucibles made of different materials with different sizes in the Universal Multizone Crystallizator (UMC) developed in the Institute of Material Sicence at University of Miskolc. Single crystals were obtained as a result of the resolidification. The quality of the single crystals was verified with neutron diffraction, then the ones having suitable quality were oriented crystallographically by using the Laue method. By using the spark machining method, seed crystals with suitable orientation were cut from the single crystals, and oriented single crystals will be grown from them.
Effect of a Rotating Magnetic Field on the Solidified Structure of Al-Si Alloys
Authors: Kovác Jenő , Roósz András , Szőke János
Published: March 2009

The aim of our research work is to study the microstructure formation during casting of technical alloys under diffusive and magnetically controlled convective conditions on earth and in space. Unidirectional solidification experiments under steady-state conditions were performed with Al-Si binary alloys containing three different amounts of Si, using electromagnetic stirring of the melt. The influence of the rotating magnetic field on the microstructure evolution (particularly on the secondary dendrite arm spacing) as compared to experiments without stirring was studied.
Columnar-to-Equiaxed Transition in SOLidification Processing (CETSOL): A Project of the European Space Agency (ESA) - Microgravity Applications Promotion (MAP) Programme
Authors: Gandin Charles-André , Billia Bernard , Zimmermann Gerhard , Browne David J. , Dupouy M.D. , Guillemot G. , Nguyen-Thi Henri , Mangelinck-Noël Nathalie , Reinhart Guillaume , Sturz Laszlo , McFadden Shaun , Banaszek Jerzy , Fautrelle Yves , Zaïdat K. , Ciobanas A.
Published: March 2009

The main objective of the research project of the European Space Agency (ESA) - Microgravity Application Promotion (MAP) programme entitled Columnar-to-Equiaxed Transition in SOLidification Processing (CETSOL) is the investigation of the formation of the transition from columnar to equiaxed macrostructure that takes place in casting. Indeed, grain structures observed in most casting processes of metallic alloys are the result of a competition between the growth of several arrays of dendrites that develop under constrained and unconstrained conditions, leading to the CET. A dramatic effect of buoyancy-driven flow on the transport of equiaxed crystals on earth is acknowledged. This leads to difficulties in conducting precise investigations of the origin of the formation of the equiaxed crystals and their interaction with the development of the columnar grain structure. Consequently, critical benchmark data to test fundamental theories of grain structure formation are required, that would benefit from microgravity investigations. Accordingly, the ESA-MAP CETSOL project has gathered together European groups with complementary skills to carry out experiments and to model the processes, in particular with a view to utilization of the reduced-gravity environment that will be afforded by the International Space Station (ISS) to get benchmark data. The ultimate objective of the research program is to significantly contribute to the improvement of integrated modelling of grain structure in industrially important castings. To reach this goal, the approach is devised to deepen the quantitative understanding of the basic physical principles that, from the microscopic to the macroscopic scales, govern microstructure formation in solidification processing under diffusive conditions and with fluid flow in the melt. Pertinent questions are attacked by well-defined model experiments on technical alloys and/or on model transparent systems, physical modelling at microstructure and mesoscopic scales (e.g. large columnar front or equiaxed crystals) and numerical simulation at all scales, up to the macroscopic scales of casting with integrated numerical models.
The Application of Some Probability Density Functions on Heterogeneous Nucleation
Authors: Fraś Edward , Wiencek K. , Burbelko Andriy A. , Górny M.
Published: March 2009

Probability density functions of known statistical distributions (Gauss, Weibull, lognormal) have been used to describe the nucleation of grains during solidification. Empirical nucleation data for solidification of cast iron follow a model based on the lognormal distribution.
Computational Modeling of Macroscopic Transportation in Continuous Castings
Authors: Zhang Huan Xin , Shen Hou Fa , Liu Bai Cheng
Published: March 2009

Macroscopic transportation in a continuous casting is modeled using the SIMPLER
algorithm and the finite difference method. The simulation software Visual Cast has been developed to describe meniscus profile, fluid flow, solidification and centreline segregation based on the volume of fluid function and the mass, momentum, energy, and species conservation equations. It is found that the meniscus profile is coherently related to the position of circumfluence in the continuous casting mold. When the vortex above the flow jet from the nozzle is close to the meniscus, the level fluctuation becomes prominent. The centreline segregation is affected by the
thermosolutal convection. The species concentration in the mush of the strand rises quickly and reaches a maximum at the end of the solidification.
Microstructural Evolution of a Commercial 0.04%C Steel During Batch Annealing
Authors: Millán J.C. , Rivas A.L. , Cabrera Jose María , Camero Sonia , Kestens Leo
Published: March 2009

The effect of heating rate and annealing time on the microstructure and texture of a
commercial 0.04 %C steel, cold rolled up to 80 %, is studied. Samples have been isothermally annealed at various heating rates (12 °C/h, 20 °C/h, 40 °C/h and 650 °C/min) and then soaked at 700 °C for 15 hours. The microstructural evolution of the samples during the heating process and hold period has been followed by optical microscopy, scanning and transmission electron microscopy. The electron back-scattered diffraction technique is used to reveal the texture of the samples. Tensile
tests and hardness measurements are correlated with the microstructural features. Results show that (a) recrystallization occurs between 600 and 650 °C; (b) a “pancake” structure develops during recrystallization at low heating rates without appreciable grain growth; (c) samples heated at 650 °C/min exhibit an equiaxed grain structure and significant grain growth; (d) only at low heating rates
the material develops a strong {111} recrystallization texture, in ccordance with the high plastic anisotropy found by mechanical testing.
Bioactive Zirconia Composites
Authors: Nogiwa-Valdez Akemi A. , Cortés-Hernández Dora A. , Almanza-Robles J.M. , Chávez-Valdez Alejandra
Published: March 2009

Zirconia-alumina composites with additions of a CaO-SiO2 glass are prepared by uniaxial pressing and sintering. In order to promote bioactivity, the composites are biomimetically treated. The effect of immersion time in simulated body fluids (SBF) and that of the presence of a wollastonite powder bed, as a calcium ion provider, on the apatite forming ability are investigated. The influence of replacing the simulated body fluids each 7-day-period for a more concentrated solution is also studied. A bonelike apatite layer is observed after 21 days of immersion when the
SBF is renewed, whether the bed of wollastonite powder is present or not. However, a thicker layer is formed by using wollastonite and the agglomerates of the apatite layer are finer on the composites containing CaO-SiO2 glass.
Microstructural Development of SiC Ceramics by Liquid-Phase Sintering with Spark Plasma Sintering Technique
Authors: Hotta Mikinori , Hojo Junichi
Published: March 2009

Sub-micron and nano-sized β-SiC powders were sintered with AlN and Y2O3 as sintering additives by spark plasma sintering (SPS). The sintered densities reached >95% of theoretical with a different molar ratio of AlN to Y2O3 at total amount of 10vol% and temperature of 1900oC for 10min in N2 atmosphere under a pressure of 30MPa. With increasing amount of the AlN additive, the size of SiC grains decreased and the shape changed from globular to columnar. The fully
densified SiC at AlN:Y2O3=95:5mol% had an average grain size of 0.5-1µm and 50-100nm in diameter by using sub-micron and nano-sized SiC starting powders, respectively. Flexural strength of the specimen having grain size of 0.5-1µm was approximately 1200MPa at room temperature.
Fabrication of Ceramic Microchannels with Tailored Pores
Authors: Sung In Kyung , Nghiem Quoc Dat , Asthana A. , Kim Dong Pyo
Published: March 2009

This paper reports fabrication of high temperature stable, chemically inert SiC and SiCN monolithic porous microchannels by micromolding in capillaries (MIMIC) method. These types of high surface area materials hold tremendous untapped potential in micro-total analysis systems, micro-reaction technology and clean energy systems. Owing to their excellent durability under harsh conditions, SiC and SiCN micro-components are imperative in fields like fuel cells, for hydrogen
generation and as environmental sensors. The report also describes the use of template particles of different size and type with diameter of ranging from 0.5 to 1.5 µm to prepare porous, high temperature stable ceramic microchannels. In the present work, ceramic porous channels have been fabricated via polymer to ceramic conversion route by using commercially available polymer precursors.
Low-Temperature Thermoelectric Properties of Zn4Sb3 Prepared by Hot Pressing
Authors: Kim Il Ho , Park J.B. , Hong Tae Whan , Ur Soon Chul , Lee Young Geun , Ryu Sung Lim , Nakamoto G. , Kurisu M.
Published: March 2009

Zn4Sb3 was successfully produced by a hot pressing technique, and its thermoelectric properties were investigated in the temperature range from 4K to 300K. The Seebeck coefficient, electrical conductivity, thermal conductivity, and thermoelectric figure of merit showed a discontinuity in variation at 242K, indicating the α-Zn4Sb3 to β-Zn4Sb3 phase transformation. Lattice thermal conductivity was found to be dominant in the total thermal conductivity of Zn4Sb3. Therefore, it is expected that thermoelectric properties can be improved by reducing the lattice
thermal conductivity inducing phonon scattering centers.
Charge/Discharge and Electrochemical Characteristics of Secondary Lithium/Pyrite Battery
Authors: Choi Jae Won , Kim Jong Uk , Ryu Ho Suk , Ahn Hyo Jun , Ahn Jou Hyeon
Published: March 2009

Iron disulfide (FeS2) is attractive as a positive electrode material in lithium batteries because of its low material cost, environmental non-toxicity, and high specific energy density. Furthermore, natural pyrite is a secondary product of the mining extraction of coal. For these reasons, natural and synthetic pyrites have been proposed as active cathode materials in secondary lithium batteries. We investigated the effect of various solvents on the electrochemical properties of
lithium-FeS2 batteries. The specific discharge capacity of Li/FeS2 cells varied from 500 to 780mAh/g based on FeS2.
Effect of Hydrothermal Conditions on the Cation Exchange Capacity of MSWI Fly Ash
Authors: Shim Young Sook , Lee Woo Keun
Published: March 2009

In this study, we studied to find the most suitable condition for the preparation of
adsorbent by hydrothermal treatment of fly ash from the municipal solid waste incinerator (MSWI). There are many variables that affect the adsorptive characteristics in our study. With the variation of which discussed the effect such as the concentration of NaOH, reaction temperature, reaction time,
solid/liquid ratio, and so on. The phase of adsorbent, its morphology and cation exchange capacity (CEC) were analyzed to evaluate their effects. The phase of adsorbent after treatment was identified by X-ray diffraction (XRD), the morphology was examined by scanning electron microscopy (SEM), and the CEC was analyzed by the ammonium acetate method. The maximum CEC value
was obtained under the condition of 3N NaOH, 100°C of reaction temperature, 12 hr of reaction time, and 1:10 of solid/liquid ratio. The CEC was 68 meq/100g in this condition, which was 8 times the amount of raw fly ash.
Microstructure and Thermoelectric Properties of P-Type Bi0.5Sb1.5Te3 Compounds Prepared by Spark Plasma Sintering
Authors: Cho Won Seung , Cho Dong Choul , Lim Cheol Ho , Lee C.H. , Hwang Woon Suk , Yoo Yeon Chul
Published: March 2009

The microstructure and thermoelectrical properties of the 4wt% Te doped p-type
Bi0.5Sb1.5Te3 compounds, fabricated by using spark plasma sintering in the temperature ranging from 250°C to 350°C, were characterized. The density of the sintered compounds was increased to 99.2% of theoretical density by carrying out the consolidation at 350oC for 2 min. The Seebeck coefficient, thermal conductivity and electrical resistivity were dependent on hydrogen reduction
process and sintering temperature. The Seebeck coefficient increased with reduction process while the electrical resisitivity significantly decreased. Also, the electrical resistivity decreased and thermal conductivity increased with sintering temperature. The results suggest that the carrier density and mobility vary with reduction process and sintering temperature. The highest figure of
merit of 3.5×10-3/K was obtained for the compounds spark plasma sintered at 350°C for 2 min by using the hydrogen-reduced powders.
Surface Strengthening of Polymer Micromold Using Electroless Ni-P Deposition
Authors: Choi Jae Woong , Hong Seok Jun , Hwang Gil Ho , Kang Sung Goon
Published: March 2009

In this work, we made micromolds using SU-8 photoresist and adopted electroless Ni-P deposition, well known as a hard coating material, to improve the rigidity and durability of SU-8 micromolds. After a micromold using SU-8 was defined by conventional lithography, Ni-P layer was electrolessly deposited on SU-8. By means of electroless Ni-P deposition, it was possible to increase the hardness of a micromold as much as about 17 times. In addition, it will be able to make various sized micromolds with one photomask by regulating the thickness of Ni-P layer.
Effects of Constituents in Bio/Photocatalytic Hydrogen Production System Using Experimental Design Tool
Authors: Joo Hyun Ku , Lee Sang Bong , Shul Yong Gun , Ha Jin Wook
Published: March 2009

This study investigated the effects of constituents in bio/photocatalytic hydrogen
production system using an experimental design tool, a fractional factorial design. The factors considered included species of buffer solution, the amount of hydrogenase (Pyrococcus furiosus, Pfu), electron donor, reaction temperature and electron mediator. The experiments were designed to determine critical conditions that were required to achieve the highest level of H2 production.
Sliding Friction and Wear Properties of Composite Reinforced by Mullite
Authors: Lee Han Young , Cho Bum Rae
Published: March 2009

Plate-on-disc type sliding friction and wear test was conducted to investigate the friction and wear properties of mullite reinforced composite (M composite), and compared with glass fiber reinforced composite (GF composite). The friction and wear test revealed that M composite has good wear resistance under mild sliding conditions, but the wear rate gradually increases under severe sliding conditions. M composite exhibited higher friction coefficient than GF composite at
room temperature and maintained the friction coefficient stably at higher temperatures. The composite film formed on counter material against M composite showed influences on the friction and wear properties under severe sliding conditions.
Dispersion Stability of Ni Nanoparticles in Ethanol with Poly (1-Vinyl-2-Pyrrolidone)
Authors: Lee Eun Hee , Lee Min Ku , Rhee Chang Kyu
Published: March 2009

The stability of nanosized Ni dispersions with varying concentrations of poly (1-vinyl-2- pyrrolidone) (PVP) was investigated by means of a visual inspection, transmission profile measured by Turbiscan, zeta potential, and transmission electron microscopy. For dispersions with PVP, the ζ potential values varied from positive charge to negative charge. For dispersion with a 0.04 weight
percentage of PVP, the ζ potential value showed 31.71 mV, which was the highest value, and the flocculation of Ni nanoparticles was not observed. Stable dispersions of Ni nanoparticles were produced by electrostatic, steric interactions, and the formation of bridging aggregation.
Castability, Tensile and Creep Properties of Mg-xAl-Zn with Variation of Al Content
Authors: Song Dae Hyun , Lee C.W. , Nam K.Y. , Lee S.W. , Park Yong Ho , Cho Kyung Mok , Park Ik Min
Published: March 2009

The effect of Al content on the castability, tensile and creep properties of Mg-xAl-Zn alloy was investigated. The molten Mg-(3~11)Al-Zn alloys of 700°C were poured into the mould designed to estimate castability. Tensile and creep tests were performed for the alloys. The results show that the castability increased with higher Al content. Creep resistance decreased while tensile strength
improved with increasing Al amount. Our microstructure study revealed that morphology of Mg17Al12 is the main factor determining the tensile and creep properties of as cast Mg-xAl-Zn alloys. The final purpose of this study is to develop the heat resistant Mg alloys to be applied in transportation systems such as automobile. Further research will be conductedon the effect of heat
treatment and additional alloying elements on the microstructure and properties of Mg-xAl alloys.
Photo-Decomposition Property of Thermal Sprayed TiO2 Coatings
Authors: Yi Zeng , Wu Wei , Liu Jun Tao , Gao Jian Hua , Ding Chuan Xian
Published: March 2009

TiO2 is a promising photocatalyst due to its excellent photocatalytic activity, physical and chemical stabilities. Plasma spraying technology is good way to prepare for TiO2 coating. The effect of spraying parameters on photocatalytic performance was studied. The results showed that both the amount of unmelted particles and the porosity of as-sprayed TiO2 coatings increased with the increasing of Ar gas flow rate. And the external bias could improve TiO2 coating’s photocatalytical
performance. The improvement degree is closed related its grain size and porosity.
Modified Fabric and Its Electromagnetic Protection Characteristics
Authors: Zhang Xiao Ning
Published: March 2009

A metallic modification technique on fabric is put forward in this paper. Morphologies and element analysis of modified fabric samples with copper and nickel-iron double films were carried out by using SEM and EDX. Shielding effectiveness (SE) on the samples was tested within 0.1~1000MHz and 1.5~18GHz. Within 0.1~1000MHz, modified fabric SE is between –93dB and –110dB. Two nickel-plated methods were compared. The measurement results of two modified fabric indicate that nickel-iron alloy films are better than nickel film on SE. With the advantages of low cost, flexibility , high electromagnetic protection characteristics, the modified fabric has a widely applicable foreground.
Optimization of Sheet Metal Process Parameters of a Shield Case Piece Using Computer Simulation
Authors: Curiel M.C. , Aum Ho Sung , Lira-Olivares Joaquín
Published: March 2009

Numerical simulations based on Finite Element Analysis (FEA) are widely used to
predict and evaluate the forming parameters before performing the physical processes. In the sheet metal industry, there are basically two types of FE programs: the inverse (one-step) programs and the incremental programs. In the present paper, the forming process of the shield case piece (LTA260W1-L05) was optimized by performing simulations with both types of software. The main
analyzed parameter was the blankholding force while the rest of the parameters were kept constant. The criteria used to determine the optimum value was based on the Forming Limit Diagram (FLD), fracture and wrinkling of the material, thickness distribution, and the principal strains obtained. It was found that the holding force during the forming process deeply affects the results, and a range of values was established in which the process is assumed to give a good quality piece.
Characteristics of Spent Foundry Sand - Loess Mixture as Ceramic Support Materials
Authors: Rhee Seung Whee , Lee Woo Keun
Published: March 2009

Spent foundry sand (SFS) from cast iron industry mixed with loess was characterized to recycle spent foundry sand as ceramic support materials. Since SFS mostly consists of sand including binding agents and residue [1], it was used as permeable media, and loess, which has highly adsorptive and reactive properties, was used as support materials Leaching tests such as Korean Leaching Test (KLT) and TCLP (Toxicity Characteristics Leaching Procedure) showed that spent foundry sands from cast iron industry were not hazardous. Turbidity in furan sand was much higher than that in other sands, and turbidity was almost not
changed with increasing amount of loess. The order of ORP (oxidation-reduction potential) in spent foundry sands was green sand > furan sand > CO2 sand. ORP was decreased with the amount of sand in furan sand and CO2 sand but was increased with the amount of sand in green sand. Hence, mixture of SFS and loess can be used as ceramic support materials with reductive or oxidative capability.
High Temperature Oxidation of Electroplated Cr-C Coating
Authors: Lee Dong Bok , Kwon Sik Chol
Published: March 2009

The oxidation of Cr-12.7 at.%C coatings electrodeposited on steel was studied at 700 and 800oC in air. The coatings, which consisted of nodular grains having microcracks and pits, had either an amorphous or a microcrystalline structure. They changed to crystalline Cr during oxidation. The oxidation resulted in the formation of Cr2O3, which provided good oxidation resistance to the coating. However, the presence of microcracks and pits in the coating was harmful to oxidation resistance.
A Novel Formulation for the Modification of Transition Metal Oxide Surfaces for Antifogging Optical Application
Authors: Asthana Yamini , Kim Dong Pyo
Published: March 2009

Formation of coatings with combined properties of being superhydrophilic /
superhydrophobic is of immense applications in the field of optics. In our present work, we developed a hydrophilic, antifogging, transparent, and stable coating by employing an anionic electrolyte, Tiron and dip-coating of organic-inorganic mixture. One of the attempts was to adhere Tiron on metal oxide surface by chelating effect, and the other one was to apply an organicinorganic coating on glass or lens substrate. The latter was formulated by mixing appropriate ratios of organic silanol coupling agents and diacrylates component for strong adhesion to the
substrate, and inorganic component of a hybrid mixture of silica, titania and Tiron for the antifogging behavior. The surface chemistry of the coated films was studied by taking ATR-IR measurements, and the wetting behavior was characterised by contact angle measurement
Thermal Stability of 40Cr Steel with Surface Nanocrystallization
Authors: Liu Yu Liang , Xiong Tian Ying , Yang Ke
Published: March 2009

Surface Nanocrystallization(SNC) is a new method of fabricating nanostructured
materials while thermal stability is an important problem for the application of nanostructured materials. A nanostructured layer was fabricated on the surface of 40Cr steel by Supersonic Particles Bombarding method, and the variation of microstructure and microhardness of nanostructured layer was studied. Nanostructured surface layer showed high thermal stability.
Improvement of Corrosion Resistance of Stainless Steel by ZrO2-SiO2 Sol-Gel Coatings
Authors: Shin Dae Yong , Kim Kyung Nam , Nam In-Tak , Han Sang Mok
Published: March 2009

ZrO2-SiO2 coatings deposited on 316 L stainless steel were prepared to protect chemically the substrates by sol-gel process using Zr(OC3H7
n)4/Si(OC2H5)4 as precursors. The influence of the ZrO2-SiO2 coatings on the corrosion resistance of the 316 L stainless steel was evaluated with the
potentiodynamic polarization curves in deareated 15% H2SO4 solutions at 25, 40 and 50 °C . Comparative test was performed on uncoated one. The values of the electrochemical parameters explain how. ZrO2-SiO2 films increase the resistance of stainless steel against corrosion.
Microstructure Evolution with Solidification Rates in IN 738LC Superalloy
Authors: Kim H.C. , Kim Y.H. , Jung Yeon-Gil , Lee Je Hyun , Jo Chang Yong , Paik Ung Yu
Published: March 2009

The morphological evolution and growth mechanism of solidification interface with
solidification rates were investigated in the Ni-base superalloy, IN738LC, by directional solidification and quenching technique under a relatively high thermal gradient of 20.5oC/mm. The planar interface of the MC-γ eutectic was found at the low solidification of 1 µm/s, and the dendritic interface formed above 5 µm/s. The dendrite lengths increased as increasing increasing solidification rate, and the
dendrite tip temperature was close to the liquidus temperature at 50 µm/s. The carbide morphologies were blocky-type and rod-type in the planar interface of low solidification rates, and as the solidification rate increased, the carbide shape changed from script type to spotty type. The phase transformation temperatures from the dendrite to MC carbide and eutectic were estimated by DTA
and by the solid/liquid interface morphology by directional solidification.
Effects of La2O3 on the Piezoelectric Properties of Lead-Free (Bi0.5Na0.5)0.94Ba0.06TiO3 Piezoelectric Ceramics
Authors: Son Y.-J. , Choi Y.G. , Kwon Joon Chul , Cho K.W. , Kim Young Moon , Kweon Soon Young , Hong Tae Whan , Lee Young Geun , Ryu Sung Lim , Yoon Man Soon , Ur Soon Chul
Published: March 2009

In an approach to acclimate ourselves to the recent ecological consciousness trends, a lead free piezoelectric material, bismuth sodium barium titanate (Bi0.5Na0.5)0.94Ba0.06TiO3 (BNBT), was considered as
an environment-friendly alternative to the PZT system. A perovskite BNBT was synthesized by the conventional bulk ceramic processing technique.La2O3 as a dopant was incorporated into the BNBT system up to 0.025 mol, and the doping effects on subsequent piezoelectric and dielectric properties were
systematically investigated. In the case of La2O3 addition, the formation of grain boundary coherency was remarkably increased, and the sintered density was increased with increasing La2O3 contents. Piezoelectric and dielectric properties were shown to have the maximum value at 0.02 mol of La2O3 addition. La3+ ions
were believed to act as a softener in the BNBT system and to enhance dielectric and piezoelectric properties in this study.
Etching Mechanism of Pb-Free Glasses in Acid Solution for Barrier Ribs in Plasma Display Panel
Authors: Kim Jae Myung , Kim Hyung Sun
Published: March 2009

We present the preliminary results of our research on the behavior of lead free glasses in the acid etching process, which is used for the formation of barrier ribs in plasma display panel. The glasses (BaO-B2O3-ZnO system) were etched in HNO3 solution (0.1-1.0% HNO3) at 50°C. The structure and surface of the etched bulk glass were investigated by using inductively coupled plasma and X-ray photoelectron spectroscopy. As a result, Ba (3-35ppm/min) and Zn (2-
27ppm/min) ions as major components were leached in the solution. A decrease of the bridge oxygen and a relative increase of non bridge oxygen in the etched glass were found by X-ray photoelectron spectroscopy.
The Effect of Meta Kaolines on the Activation of Waste Concrete Sludges
Authors: Kim Jae Jun , Youn Sang Heum , Hwang Kyu Hong , Yoon Jeong Bae , Lee Sung Gap , Jun B.S. , Lee Jong Kook , Yoon Seog Young , Kim Hwan
Published: March 2009

Waste sludges produced from the recycling of concretes contain a large amount of aggregate powders and pre-reacted cements so that they have no more cementing properties. However, since they contain unreacted Ca(OH)2, pozzolanics such as blast slag or meta kaoline can activate the waste concrete, and they can be reused as low-grade cement or pozzolanics. When meta kaoline was added with some other pozzolanic materials such as gypsum or blast slags, the density was increased so that the compressive strength, especially early stage of curing
time, was enhanced. When meta kaolin was added, more densified C-S-H gel networks were formed at aggregates, and ettringites were produced between the C-S-H gel networks.
Fabrication Characteristics of Mineral Wool Fiber Used the Waste
Authors: Kang Ki Hwan , Kim Sang Youl , Um Yong Su , Hur Bo Young
Published: March 2009

The development of mineral wool core sandwich panel depends on the reaction of resin on mineral wool and face sheet. The most important factors in developing the mineral wool core are optimization of the Curing system and density of the used resin. In addition, this product considers the functional effect and good environment instead of organic form core. This paper studied the curing conditions, the density of used resin, and the functional effect after manufacturing the mineral wool core.
Polymer/Inorganic Composite Materials for Quick Repair of Cement Concrete Pavement
Authors: Ding Hua , Xiang Ruili , Song Zhi Min , Yu Zi Li
Published: March 2009

Composites of polymer/inorganic materials have comprehensive properties and they are widely used in many fields of the industry. In the present work, methacrylate copolymer/silica composite materials were prepared by mixing and blending process. The mechanical properties such as flexural, compressive strength of yield composite were obtained as the function of mixing ratio. The optimized composite materials have been used as quick repair materials in the Chengyu (Chengdu to Chongqing) highway, southwest China. The results showed that the composite material was better than cement concrete rehabilitation, and the traffic could be allowed to open over repaired patches after 1.5-5 hours.