bluuebunny/crossref_metadata_2025 huggingface dataset:
A Web-Based Embedded Sequential Controller with USB 1-N Wireless I/O Modules
Authors: Sheu Yung-Hoh , Li Wu Jeng , Chen Yen Chao , Yang Jheng Yi
Published: March 2009

This paper designs web-based USB 1-N wireless I/O modules embedded sequential
controller. The controller consists of ARM-based core system, a set of USB 1-N wireless I/O data acquisition modules, and sequential control software.
The ARM-based core system running Linux operation system forms the basic hardware/software foundation of the controller. The set of USB devices used as I/O interface (sensor and actuator) of thecontroller. With the use of RF chip, the USB I/O is cascaded by wireless 1-N channel such that multiple data acquisition modules can communicate with the controller by a USB port. The device
driver of the USB set for the ARM-base Linux system is developed.
The sequential control software is designed as client/server structure. The server-side program and client-side program communicate through the Internet. The server-side control program, mainly a PLC interpreter, is an application developed in C++ in the Linux system. The client-side control program is developed in Java and put under a web server of the controller such that the program can be easily deployed by network and run in remote computer. The client program is also used as GUI of the controller.
Nonlinear Recursive Formulation for Kinematic and Dynamic Analysis of Robotic Manufacturing Systems
Authors: Hwang Yunn Lin
Published: March 2009

The objective of this paper is to develop a nonlinear recursive formulation for the dynamic analysis of robotic manufacturing systems. The nonlinear recursive equations are used for open-loop flexible manipulators that undergo large translational and rotational displacements. These equations are formulated in terms of a set of time invariant scalars, vectors and matrices that depend on the
spatial coordinates as well as the assumed displacement fields, and these time invariant quantities represent the dynamic manufacturing couplings between the rigid body motion and elastic deformation. This formulation applies recursive procedures with the nonlinear equations for flexible manipulators to obtain a large, loosely coupled system equation of motion in robotic manufacturing
systems. The numerical techniques used to solve for the system equations of motion can be more efficiently implemented in any computer systems. The algorithms presented in this investigation are illustrated by using standard mechanical joints for robotic manufacturing systems that can be easily extended to other special joints. The nonlinear recursive formulation developed in this paper is illustrated by a robotic manufacturing system using standard revolute mechanical joints.
A Relative Method for Finite Element Nonlinear Structural Analysis
Authors: Choi Jin Hwan , Bae Dae Sung , Cho Hui Je
Published: March 2009

Nodal displacements are referred to the initial configuration in the total
Lagrangian formulation and to the last converged configuration in the updated
Lagrangian formulation. This research proposes a relative nodal displacement method to represent the position and orientation for a node in truss structures. Since the proposed method measures the relative nodal displacements relative to its adjacent nodal reference frame, they are still small for a truss structure undergoing large deformations for the small size elements. As a consequence, element formulations developed under the small deformation assumption are still valid for structures undergoing large deformations, which significantly simplifies the equations of equilibrium. A structural system is represented by a graph to systematically develop the governing equations of equilibrium for general systems. A node and an element are represented by a node and an edge in graph representation, respectively. Closed loops are opened to form a
spanning tree by cutting edges. Two computational sequences are defined in the graph representation. One is the forward path sequence that is used to recover the Cartesian nodal displacements from relative nodal displacements and traverses a graph from the base node towards the terminal nodes. The other is the backward path sequence that is used to recover the nodal forces in the relative coordinate system from the known nodal forces in the absolute coordinate system and traverses from the terminal nodes towards the base node. One closed loop structure undergoing large deformations is analyzed to
demonstrate the efficiency and validity of the proposed method.
Studies on CCD On-Line Detection in Curve Grinding
Authors: Zhang Yong Hong , Tang Hui Qiang , Bu Quan Lin , Hu De Jin
Published: March 2009

An on-line image measurement system for curve grinding was schemed out according to the working process. Because of interaction between detection precision and field of view, it is difficult to realize high detection precision at a large field of view. In order to settle this problem, a detection method based on circular tolerance zone was presented according to grinding process and wheel shape. Real-time images of work piece can be gathered while using synchronal control and
outer trigger technology. Using curve fitting method, the work piece image edge can be located to sub-pixel values. Experiments show that the proposed method in this paper is effective, and its detection precision and results are reasonable.
Process Reengineering of Collaborative Mold Design and Manufacturing – A System Engineering Evaluation Approach
Authors: Trappey Amy J.C. , Lu Tung-Hung
Published: March 2009

One of the most popular mathematical tools in fields of robotics, mechanisms and
computer graphics is the 4x4 homogeneous transformation matrix. In previous work we applied this matrix to the optical domains of flat and spherical surfaces for: (1) skew ray tracing to determine the paths of skew rays being reflected/refracted; (2) sensitivity analysis to determine by direct mathematical analysis the differential change of incident point and reflected/refracted vector with
respect to change in incident light source. The present work extends our previous work to include the case of parabaloidal boundary surfaces.
A Fully Integrated System for Cell/Particle Sorting in a Microfluidic Device Utilizing an Optical Tweezing and DIP Recognition Approach
Authors: Chien Yu Sheng , Lin Che Hsin , Kao Fu Jen , Ko Cheng Wen
Published: March 2009

This paper proposes a novel microfluidic system for cell/microparticle recognition and manipulation utilizing a digital image processing technique (DIP) controlled optical tweezer under microfluidic configuration. Cell/microparticle samples are firstly electrokinetically sorted in a microfluidic channel and pass through an image detection region. Digital image processing technique is used to count and recognize the cell/particle samples and then sends control signals to generate laser pulses to manipulate the target cell/particles optically. The optical tweezer system is capable of
catching, moving and switching the target cells within the microfluidic channel. The trapping force of the optical tweezer is also demonstrated utilizing the relationship between Stocks-drag force of microparticles and the applied electroosmotic flow. The proposed system provides a simple but high-performance solution for microparticle manipulation in a microfluidic device.
Operation Principle and Simulation of Loop-Type Microfluidic Biochips
Authors: Chang Yaw-Jen , Chang Yeon Pun , Cheng Kai Yuan
Published: March 2009

Biochip is an emerging technology and has evoked great research interests in recent years. In this paper, a novel air-driven loop-type microfluidic biochip was investigated. Differing from conventional micro channels, this chip has a micro loop-channel and 3 sets of driving conduits with valveless design in their intersections so that the microfluid can be driven smoothly in unidirectional circular movements. The driving efficiency reaches the highest if the entry angle of driving conduits
is in the tangent direction of the loop-channel. However, the smaller the included angle, the impact area the larger, leading to comparatively serious reflow phenomenon. Furthermore, the microfluid can be controlled to stop almost instantaneously in the loop segment. Therefore, this loop-type
biochip is suitable for biochemical reactions under repeated multiple temperature operations such as polymerase chain reaction. A full circular movement completes a cycle of PCR amplification. Besides, this biochip has its merits including simpler chip design, shorter channel length, and flexible controllability for biochemical reactions.
Using Magnetic Nanoparticles to Enhance Gene Transfection on Magneto-Electroporation Microchips
Authors: Li Min , Lin Yu Cheng , Su Kai Chun
Published: March 2009

This study demonstrated that DNA associated with magnetic nanoparticles can be attracted to specific areas of cell surfaces under magnetic fields, which highly increased the DNA concentration at specific areas and further enhanced the gene transfection in an electroporation (EP) method. The superparamagnetic nanoparticle’s distribution could be operated by magnetic field, where the gravity effect could be neglected. Compared with the electroporation with and without
electrostatic attracting force, the magneto-electroporation with magnetic attracting force showed higher delivery rate (63.05 %) in the electroporation processes. Simulating an asymmetric magnetic field helps to create experiment environment with different intensities of magnetic flux density. The resultant difference can be identified by the profile of fluorescence. This report focused on
enhancement and targeting of gene transfection using 6 nm γ-Fe2O3 nanoparticles and electroporation microchips.
Quantum Dots CdSe/ZnS-Loaded Poly(D,L-Lactide-Co-Glycolide) Nanoparticles: Physicochemical Characterization and Application
Authors: Yang Chih Hui , Lin Kuo Chin , Chang Yu Huai , Lin Yu Cheng
Published: March 2009

This paper described and characterized the quantum dots (QDs) with/without the
polymeric PLGA applied in MC3T3E-1 delivery. Neat QDs were treated with various solvents, temperatures, exposure time and concentration to evaluate their stability and efficacy. We found that the intensity degree of fluorescence spectra (QDs) in different solvents follows the order: ether > THF > acetone > chloroform > methanol. Importantly, the QDs become inactive after 8-hr dissolution in
the solvents of ether, THF or chloroform. According to this result, acetone and methanol are ideal solvents for QDs. The optimum concentration range of QDs in acetone is 5 to 10 mg/mL. We found that no obvious difference of fluorescence intensity was detected in QDs stored respectively at 4 °C, 24 °C and 44 °C (8-hour). When QDs were exposed to UV light (312 nm) for 2 hr, serious decay of
fluorescence intensity was observed. In order to extend the application of QDs in medical areas, we encapsulated them in individual biocompatible poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles for in-vitro imaging of endocytosis in MC3T3E-1 cells. We demonstrated that the polymeric PLGA have the ability to permeate the cells for cellular internalization; the endocytotic activity could be
enhanced by the polymeric QDs-encapsulated PLGA.
Fabrication and Characterization of 3D Aspheric Microlenses with Arbitrary Surface Profiles Based on a Novel Excimer Laser Contour Scanning Method
Authors: Lee Yung Chun , Wu Chun Ying
Published: March 2009

This paper presents a new method for fabricating 3D microstructures with an excimer laser micromachining system. A novel mask contour scanning method is developed for obtaining precise 3D microstructures with pre-described continuous surface profile. Two different microlenses with spherical and aspheric surfaces profiles with dimension less than 200 μm are fabricated on polycarbonate (PC) samples. The surface profiles are measured and compared with their theoretical
counterparts. Excellent agreements both in profile shapes and dimensions are achieved. The surface roughness (Ra) of the machined surfaces is also measured and is less than 10 nm. The machining profile accuracy and surface smoothness of this proposed micromachining method show great potentials in fabricating micro-optic components such as aspheric microlenses or microlens arrays.
Study on Thin Wall Injection Molding Formability and Property of Graphite-Polymer Composite Bipolar Plate for Proton Exchange Membrane Fuel Cell
Authors: Hsu Chaug Liang , Chang Ke Ming
Published: March 2009

The electricity is the most important motive power in the world for the economy and the industry. But today the electricity is always generating by natural gas, oil, and coal, hence environment pollution caused by fossil fuel will be more serious, and crude oil will be used up in 40-50 years (according to the report of Statistical Review of World’s Energy’s Research), it is need to develop a high efficiency and zero-emission in new energy.
Computer Modeling of Extrusion by the Rigid-Plastic Hybrid Element Method
Authors: Guo Yong Ming
Published: March 2009

In this paper, a rigid-plastic hybrid element method is formulated, which is a mixed
approach of the rigid-plastic domain-BEM and the rigid-plastic FEM based on the theory of slightly compressible plasticity. Since compatibilities of velocity and velocity's derivative between adjoining boundary elements and finite elements can be met, the velocity and the derivative of velocity can be calculated with the same precision for this hybrid element method. While, the compatibility of the
velocity's derivative cannot be met for the rigid-plastic FEMs.
An Elasto-Plastic Finite Element Analysis of the Hat-Type Drawing Process of Sheet Metal
Authors: Chen Tsung Chia , Huang You Min
Published: March 2009

This study aims to clarify the process conditions of the hat-type drawing of a sheet metal of steel. It provides a model that predicts not only the correct punch load for drawing, but also the precise final shape of products after unloading, based on the tensile properties of the material and the geometry of the tools used. An elasto-plastic incremental finite-element computer code, based on an updated
Lagrangian formulation, was developed to simulate the hat-type drawing of sheet metal. In particular, selective reduced integration was adopted to formulate the stiffness matrix. The extended r-minimum technique was used to deal with the elasto-plastic state and contact problems at the tool-metal interface. A series of simulations were performed to validate the formulation in the theory, leading to the development
of the computer codes. The whole deformation history and the distribution of stress and strain during the forming process were obtained by carefully considering the moving boundary condition in the finite-element method. Results in this study clearly demonstrated that the computer code for simulating the hat-type drawing process was efficient.
The Hydroforming of Micro-Square Tubes With Non-Equal Section and Dendritic Shape
Authors: Hsu Yuan Chuan , Yang Tung Sheng , Wu J.L. , Chen Y.X.
Published: March 2009

Currently, tube hydroforming and metal micro-forming technique have emerged as the attractive and important developing tendencies in industry. Hence, in this study, the finite element simulation technique was employed to investigate the micro-hydroforming for making the micro-square tube with non-equal section and dendritic shape from square tube. Results of the current study show that the deformation of micro-square tube can be effectively analyzed by finite element simulation. The bulging and wall thinning of the tube are severely influenced not only by the internal hydraulic pressure but also by the punch axial feeding speed.
Prevention of Seizure in Deep Drawing Using Plastic Die
Authors: Harada Yasunori , Murao T. , Mori Kenichiro , Tsuchida Noriyuki , Fukaura Kenzo
Published: March 2009

In this study, deep drawing using plastic die was investigated to prevent seizure during forming. In the deep drawing process of aluminum and titanium sheets, seizure was found to occur during forming due to a high reactivity with other metals. For the prevention of seizure, plastic dies were used in this study. These plastic materials have a good resistant to seizing, since no seizure occurs in the contact surface of the metal and plastic material. Moreover, the effects of seizure and
wearing die on the dimensional accuracy of drawn cups were examined using nylon die. The blanks used were pure aluminum, aluminum alloy A5052 and pure titanium. The blanks could be successfully formed with a water lubricant. To increase the dimensional accuracy of the drawn cups, deep drawing using fiber-glass-reinforced nylon and plastic composite steel die was also attempted. It was found that the use of plastic die was very effective in preventing of seizure.
Joint Design and Fabrication for Mechanical Elastic Self-deformation Micro-Assembly Technology
Authors: Kuo Chia Lung , Huang Jing Dae
Published: March 2009

A microstructure assembled into another part using the mechanical elastic
self-deformation assembly technology is proposed in the paper. To attain the self-deformation during assembling, the assembly joint on the microstructure is analytically designed as the feature with an appropriate taper and cross clearance. Take account of the accuracy, the whole process from micro-fabrication to micro-assembly is carefully planned and practiced under a micro-EDM machining center system which consists of vertical micro-EDM with dividing mechanism, and
horizontal micro-machining mechanism, which is referred to as on-process micro-assembly. To illustrate the micro-assembly strategies and procedures, a micro-rotor production including assemble a tungsten carbide four-phase micro-rotor into an alumina base has been provided and discussed.
The Use of the Taguchi-Grey Based to Optimize High Speed End Milling with Multiple Performance Characteristics
Authors: Hwang Shen Jenn , Hwang Yunn Lin , Lee B.Y.
Published: March 2009

This paper presents a new approach for the optimization of the high speed machining (HSM) process with multiple performance characteristics based on the orthogonal array with the grey relational analysis has been studied. Optimal machining parameters can then be determined by the grey relational grade as the performance index. In this study, the machining parameters such as
cutting speed, feed rate and axial depth of cut are optimized under the multiple performance characteristics including, tool life, surface roughness, and material removal rate(MMR). As shown experimental results, machining performance in the HSM process can be improved effectively through this approach.
Ultrasonic Aided Electrical Discharge Grinding of Hard Materials Using a Metal Matrix Composite Electrode
Authors: Shih Hung Rung , Shu Kuen Ming
Published: March 2009

The main object of the present work was to develop an ultrasonic aided electrical
discharge grinding (UAEDG) methodology to remove the re-solidified layer through the grinding induced by a metal matrix composite electrode prior to the re-solidification of molten material. A metal matrix composite (Cu/SiCp) electrode, with an electroless pretreatment of Cu coating on SiCp to enhance bonding status between Cu and SiCp, was employed to study the UAEDG technology.
The machinability of the mold steel SKD11 was investigated by the combined technologies of UAEDG. The machined surfaces of these materials were examined by optical microscopy（OM）and their surface roughness measured by a profilemeter.
Finite Element Analysis of the Hydro-Mechanical Punching Process
Authors: Yoon Jong Hun , Huh Hoon , Lee Yong Shin , Kim Seung Soo , Kim E.J. , Park Hoon Jae , Choi Tae Hoon , Lee Hye Jin
Published: March 2009

This paper investigates the characteristics of a hydro-mechanical punching process. The hydro-mechanical punching process is divided into two stages: the first stage is the mechanical half piercing in which an upper punch goes down before the initial crack is occurred; the second stage is the hydro punching in which a lower punch goes up until the final fracture is occurred. Ductile fracture criteria such as the Cockcroft et al., Brozzo et al. and Oyane et al. are adopted to predict the fracture of a sheet material. The index value of ductile fracture criteria is calculated with a user material subroutine, VUMAT in the ABAQUS Explicit. The hydrostatic pressure retards the initiation of a crack in the upper region of the blank and induces another crack in the lower region of the blank during the punching process. The final fracture zone is placed at the middle surface of the
blank to the thickness direction. The result demonstrates that the hydro-mechanical punching process makes a finer shearing surface than the conventional one as hydrostatic pressure increases.
Spiral-Layer Machining for Making Thin-Wall Structures
Authors: Yeung Millan K. , Orban Peter
Published: March 2009

CNC machining is one of the most widely used manufacturing processes. While
possessing good flexibility and fast cycle time, there are some restrictions imposed depending on the geometry of the part to be machined. One challenge often encountered is the machining of thinwall structures. The instability and deflection of the thin-wall causes difficulty for control of the machining condition, affecting the accuracy of the modeling and simulation of the process. This paper presents an alternative machining method called spiral-layer machining that could improve
this condition using the concept of layer manufacturing technology and technologies that would reduce the machining force or tool-force variation and divert the force-vector. A case study of machining a turbine blade was conducted to verify the method. The result was successful in terms of stability and feasibility. Error correction techniques are being investigated to ensure good
dimensional precision of the part.
Development of Manufacturing Strategy - Influence of Technology Orientation and Customer Orientation: An Empirical Study Approach
Authors: Tseng Ming Lang , Chiang Jiu Hsiang , Chiu Anthony SF
Published: March 2009

Using survey data, this research identified the relationship between technology
orientation (manufacturing flexibility and advance manufacturing technology), and customer orientation (customer focus and customer satisfaction) to development of manufacturing strategy. This framework is then tested on a sample of 52 firms in plastics injection industry, Taipei County, Taiwan. The results show significant relationships in the framework with four models. They support the argument found in the literatures that manufacturing strategy builds should related to technological development and market place. Implications of the findings are discussed.
Creative Design of Metal Can Crushers with Eight Links
Authors: Hsieh Wen Hsiang , Chang Tien Sheng
Published: March 2009

The purpose of this paper is to synthesize the structure of metal cans squeezing devices with eight links based on the methodology of creative design. First, the design requirements and design constraints are specified based on the characteristic of existing squeezing devices. Then, specializing with respect to (8, 10) generalized chains, the atlas of specialized feasible chain is generated. Furthermore, the atlas of new design is obtained through the process of particularization. Finally, the atlas of new design with single toggle effect is also synthesized. In addition, the feasibility of the design is verified by a prototype machine testing.
A Simple Parameter Calibration Method for a Novel Controllable Mechanical Metal Forming Press
Authors: He Kai , Du Ru
Published: March 2009

This paper introduces a novel controllable mechanical metal forming press, which is a
2-DOF planar mechanism driven by a large constant speed motor and a small servomotor. The constant speed motor provides the main power while the servomotor tunes the trajectory and velocity of the punch in order to realize the controlled punch motion. The new press needs high accuracy, repeatability and resolution to guarantee the controlled punch motion. Improving manufacturing and
assembly process could help it, but sometimes is very difficult and not feasible. Therefore parameter calibration has a significant effect on the accuracy, repeatability and resolution of the press. In this work, a simple parameter calibration method is presented without using complex and precise metrology system. Experiment results indicate that this kind of calibration method is fast, easy,
accurate and cost effective.
Nondestructive Disassembly System for White Board Marker
Authors: Chang Tien Sheng , Hsieh Wen Hsiang , Hsieh Y.-A. , Yang C.H.
Published: March 2009

The rapidly growing concern about environmental and resource protection have stimulatedmany industrial sectors to solve the disposal problems of used products. The recovery processes canbe simply categorized into material recovery and product/component recovery. Material recoverymostly involves disassembly for separation and processing of materials of used products. Destructive
methods such as dismantling, shredding, or chemical operations are normally used. Product recoveryincludes disassembly, cleaning, sorting, replacing or repairing bad components, reconditioning,testing, reassembling and inspecting. These recovered components/products can be reused inrepairing and re-manufacturing. That provides an opportunity in bringing the used products back to an “as new” condition. This paper utilizes the concept of non-destructive method of product recovery processes and develops an automatic disassembly system for white board marker pens. The experimental results show that the cycle time for the disassembly processes is about 3.8 second that is believed to be compatible to the desired feeding rate for manufacturing. In addition, the reused rate
for the recovered components is close to 100% except the fiber-refill component.
The Influence of Serration on a Shaving Cutter with a Pre-Designed Relief Portion
Authors: Chang Shinn Liang , Wu Uei Der , Hsieh Jen Kuei , Tseng Ching Huan , Cheng Shi Duang , Chang Kuang Rong
Published: March 2009

In this paper, a shaving cutter with serration and a pre-designed relief portion manufactured by a hob cutter was designed. Due to the non-conventional manufacturing process, standard manufacturing problems were avoided and the production efficiency was enhanced as was the stiffness of the shaving cutter. Two solid models of the shaving cutter, one with the novel relief portion and the other a relief hole, were set up for stress analysis using the finite element method. The
models confirmed that the shaving cutter with the novel relief portion had a higher stiffness compared to that with a relief hole in the presence of serration.
3D Model Based Design for Control of a Mechatronic Machine Tools System
Authors: Chen Chin Yin , Cheng Chi Cheng
Published: March 2009

The goal of this research is to develop a design and optimization methodology for the
mechatronic modules of machine tools by treating all important characteristics from all involved engineering domains in one single process. In this study, a mechatronic system of machine tools was broken into a structure and control two-level systems. In the first stage for structure design process, the Pro/E was used to build up the 3D models and the AnSys was employed to design the mechanical structure and select the optimal components for the machine tools. Next, in the control design process, a common controller type was designed by MATLAB in this stage. Then, three
important parameters were established for the machine tools design to achieve the overall system performance.
Geometry Modeling for Indexing Cams Based on Screw Theory and Product of Exponential Formula
Authors: Chang Zong Yu , Yang Yu Hu , Zhang Ce , Ding Shou Bin , Zhang Bin , Tan Deng Shan , Zhu Chun Tao
Published: March 2009

This paper proposes a method of geometry modeling for indexing cam mechanism by
using screw theory and exponential product formula. Kinematic analysis based on screw theory is introduced firstly. Then, method to model surface of indexing cams is presented when screw theory and exponential product formula are applied. The paper gives examples to obtain the geometry models of roller gear cam, barrel indexing cam and parallel indexing cam. Our work suggests that this
method can avoid the burdensome work on building coordinate systems, transformation matrixes and understanding on the mechanism. Moreover, this method can be used to innovate and design new types of indexing mechanism.
Gravity-Induced Convection during Directional Solidification of Hypermonotectic Alloys
Authors: Ludwig Andreas , Wu Meng Huai , Abondano M. , Ratke Lorenz
Published: March 2009

A two-phase volume-averaging model developed for the simulation of the dynamic
decomposition and solidification of hypermonotectic alloys was used to study the occurrence of convection phenomena during directional solidification of a hypermonotectic alloy (Al-10 wt.%Bi) under terrestrial condition. The model accounts for nucleation and growth of secondary phase droplets, Marangoni and Stokes forces, solute partitioning, heat release due to decomposition and
solidification. It is shown that the appearance and growth of secondary droplets is accompanied with a continuous downwards motion of droplets, which rapidly becomes unstable. After relaxation of this dynamic motion the advancing solidification front freezes in the resulting non-uniform droplet distribution.
Simple Analytical Models for Dendrite Arm Coarsening under High and Medium Temperature Gradients
Authors: Turkeli Altan
Published: March 2009

The coarsening of secondary dendrite arms is discussed in terms of two different driving forces, which are the curvature effect and the temperature gradient zone melting (TGZM) effect. It is shown that the driving force due the TGZM effect can be higher than that due to the curvature effect at high temperature gradients and equal to each other at medium temperature gradients. For such high and medium temperature gradients, simple analytical models are proposed to predict the coarsening kinetics of secondary arms during solidification in a binary alloy. The prediction of the present analytical model agrees with experimental data obtained from the solidification of Fe – 1.6 wt. % Mn – 0.75 wt. % C steel.
Measurement of the Kinetics of Thermal Effects during Phase Transformations in ADI
Authors: Kapturkiewicz Wojciech , Fraś Edward , Lelito Janusz , Burbelko Andriy A.
Published: March 2009

The heat generation rate during austempering of ADI (Austempered Ductile Iron) for process temperatures of 250, 265, 280 and 293°C has been presented. A special measuring device was constructed. Thermal effects were quantified by analysis of the experimental temperature curves during the austempering process.
Effect of Titanium and Strontium Addition on the Fluidity of A319 and A356 Aluminum Alloys
Authors: Sánchez Samuel , Velasco E. , del C. Zambrano Patricia , Cavazos J.L.
Published: March 2009

A series of tests have been conducted to study the effect of titanium and strontium on the fluidity of liquid A319 and A356 aluminum alloys. The increase of titanium enhances the fluidity of the A319 liquid alloy due to its high potential to refine the grain size because the presence of particles increases the solid nucleation rate. For the alloy A356, the fluidity index increases with the increase of strontium, eliminating the occurrence of cold joint defects. Therefore, it is concluded
that titanium and strontium enhance the fluidity of these liquid aluminum alloys. It is expected that cast defects will be reduced. Care has to be taken, as a very fluid metal can also be harmful.
Fabrication of Photocatalytic TiO2 Thin Film Using Innovative Aerosol Deposition Method
Authors: Kim Jong Oh , Choi Won Youl , Choi Byung Kyu , Jeong Jong Tae
Published: March 2009

This research investigated the water purification performance of thin film with anatase
phase TiO2 powder having good photocatalytic property using an innovative aerosol deposition method at the normal room temperature. Fresh raw powder was dehydrated for good dispersion of TiO2 powder. To suppress the formation of second particle, the powder was dispersed for 90 minutes in alcohol bath with ultrasonic treatment and then desiccated. The average grain size of
particle was identified to be 1µm in TiO2 thin film deposited on stainless steel mesh by scanning electron microscopy (SEM). The anatase phase of TiO2 thin film was investigated by X-ray diffraction (XRD). The anatase phase of fresh raw powder was favorably maintained after aerosol deposition treatment.
Change of Formation Yield and Characterization of PCC Particle Synthesized with Impurity Ions Contents by Carbonation Process
Authors: Cho Jin Sang , Joo Sung Min , Cho Sang Hwan , Yu Young Hwan , Kim Im Ho , Kim Hwan , Han Choon
Published: March 2009

The effect of the impurity ions Al3+, Fe3+ and Mg2+ on the formation yield and crystal
properties of precipitated calcium carbonate(PCC) produced by the carbonation process was investigated in Ca(OH)2-H2O-CO2 system. The effect of the impurity ions Al3+, Fe3+ and Mg2+ on the formation yield using particle size distribution and morphology of PCC were discussed. The particle size distribution of PCC was increased with increase of impurity ions. The morphology was
transformed in order of spheroidal, scalenohedral, rhombohedral calcite for Al3+, Fe3+ and rhombospheroidal, spherical, scalenohedral for Mg2+ with increase of impurity ions.
Silicon to Silicon Wafer Bonding at Low Temperature Using Residual Stress Controlled Evaporated Glass Thin Film
Authors: Park Joon Shik , Choi Yeon Shik , Kang Sung Goon
Published: March 2009

Silicon to silicon wafer bonding at low temperature of 300 °C using residual stress
controlled evaporated 2 ㎛ thick Pyrex glass thin film (briefly, glass thin film) on silicon wafer was investigated. It was found that residual stresses of 2 ㎛ thick glass films on silicon wafers were strongly dependent upon moisture contents and annealing processes. Residual stresses of asdeposited glass films with compressive stress of -150 MPa could be changed to more compressive
stress of -230 MPa by moisture absorption. However, after annealing process at 200 °C to 400 °C for 30 min, residual stresses were remarkably changed to tensile stresses of about 75 MPa to 130 MPa, respectively. For the reliable wafer bonding process, the evaporated glass thin films should be annealed in the range of 200 °C to 500 °C for 30 min. So, bare silicon to bare silicon and bare silicon to patterned silicon were bonded at 300 °C and 30 V ~ 60 V for 15 min using 2 ㎛ thick glass film with residual stress of 130 MPa which were generated after the annealing process of 400
°C for 30 min. These results could be used for low temperature silicon to silicon wafer bondings for applications of micro sensors, micro actuators and micro fluidics devices.
Synthesis of Ceria-Coated Copper Oxide Particles for Direct Hydrocarbon SOFCs Anode
Authors: Lee Jun , Lee Seung Hun , Lee Eun A , Hwang Hae Jin
Published: March 2009

Ceria-coated copper oxide powders were prepared by the precipitation method using
cerium nitrate hexahydrate and ammonia as a precipitant. Heterogeneous nucleation and growth of ceria took place on the copper oxide surface by dispersing the copper oxide particles in cerium nitrate aqueous solution and subsequently adding ammonia into it. Process conditions such as the pH of the precursor solution and precipitation temperatures were carefully controlled for the homogeneous
precipitation of ceria particles. It was found that copper oxide was homogeneously coated with nano-sized (~20 nm) ceria particles at room temperature. The morphology of ceria and ceria-coated copper oxide powder were examined by field-emission scanning electron microscopy (FE-SEM) as a function of precipitation temperature.
Bioactivity of Plasma-Sprayed TiO2 Coating in Simulated Body Fluid by Hydrofluoric Acid Treatment
Authors: Zhao Xiao Bing , Liu Xuan Yong , Ding Chuan Xian
Published: March 2009

TiO2 coatings on titanium alloy substrates were prepared by atmospheric plasma spraying using commercial nano-powders. Then, as-sprayed coatings were treated using 10% hydrofluoric acid (HF) at room temperature for 30 seconds. As-sprayed and HF-treated titania coatings were soaked in simulated body fluid to investigate the formation of apatite on their surface. Field-emission
scanning electron microscopy was used to observe the surface morphologies, and the phase composition of the as-sprayed coating and apatite were analyzed by X-ray diffraction and energy-dispersive X-ray spectrometry. As-sprayed titania coating is composed of rutile, anatase, and a small quantity of Ti3O5. It exhibited excellent adhesion between the TiO2 coatings and titanium alloy substrates, and the bonding strength was about 38 MPa. After in vitro experiment, a new substance containing calcium and phosphate was formed on the surface of HF-treated TiO2 coatings
after being soaked in SBF, while the new substance was not formed on the surface of as-sprayed TiO2 coatings. The results indicated that the bioactivity can be induced to the surface of plasma sprayed TiO2 coatings by hydrofluoric acid treatment.
Simulation of Electric Upsetting and Forging Process for Large Marine Diesel Engine Exhaust Valves
Authors: Jeong H.S. , Cho J.R. , Lee Nak Kyu , Park H.C.
Published: March 2009

The manufacturing process of the exhaust valve in large marine diesel engines consists of an upset forging and final forming process. In the past, the exhaust valves in large marine diesel engines have been made through free forging by using the stretch forming method. This method has used the ingot and the billet as a preliminary forming process. Nimonic 80A, a superalloy, is presently used for the material of the exhaust valve. For the forming method of the valve, the
electric upset method is used. Solid bar is raised up to the forming temperature by using electric energy and is continually deformed by upset pressure. The electric upsetting processing is a useful method for the high quality of exhaust valves in large marine diesel engines. It can keep the continuous grain flow, excellent mechanical property, and corrosion resistance because of the elaborate macrostructure of the valve face. The purpose of this paper is to predict the optimum process condition through simulation of the exhaust valve with a diameter of 73mm. The experimental result of an exhaust valve with a diameter of 19mm is in good agreement with the simulation result using the “QForm” that can solve
electric upsetting problems. Finally, the optimal manufacturing process of the electric current and the upset load are surveyed.
Evaluation of Microstructure on SiCp/AZ91 Magnesium Composite Fabricated by Rotation-Cylinder Method
Authors: Lee Jung Il , Hong Tae Whan , Kim Young Jig , Kim J.S. , Park H.K.
Published: March 2009

Eco-friendly development and on-going research strategy of Rotation-Cylinder Method (RCM) is given for SiCp/AZ91 Mg composites, identifying some of the key factors that need to be controlled and indicating subsequent casting processes. RCM produces U-shaped laminar melt surface with a Rankine vortex even at high rotation speed in an ambient atmosphere, which allows quick and efficient incorporation and homogeneous distribution of SiC particulates into molten Mg
alloys. Therefore, sound SiCp/AZ91 Mg composites can be manufactured in conjunction with subsequent casting processes, such as investment casting and thixocasting. A transmission electron microscopy study showed that the interfacial reaction products consist of Mg2Si, MgO, Mg17Al12 and Al6Mn, which were analyzed using primitive cell volume and zero order Laue zone pattern and
single convergent beam electron diffraction pattern containing higher order Laue zone ring from a nanosized region.
Properties of Coating Films Synthesized from Nano Colloidal Silica and Alkoxy Silanes
Authors: Park Hoy Yul , Kang Dong Pil , Myung In Hye , Yoon Seog Young
Published: March 2009

Colloidal silica/silane sol solutions were prepared in variation with the ratio of silane to
colloidal silica. Such sol solutions were synthesized from colloidal silica/tetramethoxysilane (TMOS)/methyltrimethoxysilane(MTMS). Sol solutions were prepared by sol-gel reaction through two step reactions. To understand their physical and chemical properties, dip coating of sol solutions
was performed on the glass substrates. Contact angle and thickness of coating films increased with increasing the amount of MTMS. The surface free energy of coating films decreased with increasing amount of MTMS. Coating films were stable until 550°C. Thermal degradation temperature of coating films decreased with increasing amount of MTMS. Plastic hardness decreased with increasing amount of MTMS. Elastic portion increased with increasing amount of MTMS.
Chipless Forming Process Using Rotary Swaging Machine with Four-Dies
Authors: Lim Seong Joo , Na Kyoung Hoan , Lee C.H.
Published: March 2009

The rotary swaging process for producing solid bars, tubes or wires is often used to
obtain the chipless forming process compared with the conventional process such as the machining and welding operation. Furthermore, machined chip, dust particles, harmful gas, and surface contamination to be commonly generated at hot working during the conventional process could be eliminated as the swaging process is applied and conducted at room temperature. Experiments for swaged product were performed to analyze the influence of the swaging process on the mechanical
properties and dimensional precision in terms of surface roughness, surface hardness, and deviation of formed dimension. The changes of dimensional precision in swaged product are also checked out and considered for various process parameters such as the forming speed and the reduction in the
outer diameter. Based on the experimental results, the surface roughness is improved under the swaging process. The weight of rod shift is reduced by about 15 % from 223.5 g to 190.2 g. Thus the number of operations to produce the final product under the conventional process is larger than that under the swaging process to be able to omit the machining and welding operation, etc. This
paper demonstrates that a rotary swaging process turns out to be an environment-friendly forming process or chipless forming process without the machined chip.
Effect of Indium on Bonding between Porcelain and Au-Pt-Cu Alloy
Authors: Lee S.H. , Jung H.Y. , Doh Jung Mann , Yoon Jin Kook , Lim H.N.
Published: March 2009

Effects of 0.5 wt% Indium addition on the oxidation of Au-Pt-Cu alloy, the interfacial
microstructure and bonding strength between porcelain and Au-Pt-Cu-xIn alloys(x = 0, 0.5wt%) were investigated using scanning electron microscopy, X-ray diffractometry, transmission electron microscopy, and a tensile tester. The bonding strength of the Au-Pt-Cu and Au-Pt-Cu-0.5In alloys with porcelain was about 24.6 MPa and 49.5 MPa in average, respectively. This higher bonding
strength in the Au-Pt-Cu-0.5In alloy compared with the Au-Pt-Cu alloy without In is ascribed to the formation of In2O3 at the interface between porcelain and Au-Pt-Cu-0.5In alloy. Especially, the formation of In2O3 at the interface between porcelain and Au-Pt-Cu-0.5In alloy leads to enhancing chemical bonding between In2O3 and various oxides in porcelain, and also to improving the anchoring effect.
Effect of Al on Microstructural and Mechanical Characteristics of Plasma Electrolytic Oxide Coatings on Magnesium
Authors: Yu Byung Geel , Kim Ye Lim , Kang Kae Myung , Chang Si Young
Published: March 2009

Plasma electrolytic oxide coatings were produced on both pure magnesium and binary Mg-Al alloys containing 3, 6, 7 wt% Al, and the effect of Al on the characteristics of coatings was investigated under the processing conditions of various coating times and current. The coatings on Mg-Al alloys showed porous microstructure and some volcano top-like pores on the surface, and they
consist of MgO and Al2O3. The surface roughness became larger with increasing coating time, while it was unchanged with increasing Al content. The thickness increased with increasing coating time and showed slight dependence on Al content. The hardness was almost unchanged with increasing coating time and Al content in the coatings grown with the ratio of current, C1:C2=100:75.
Hydrogen Production by Catalytic Decomposition of Methane over Carbon Nanofibers
Authors: Han Ling , Lim Tae Ki , Kim Young Jun , Hahm Hyun Sik , Kim Myung Soo
Published: March 2009

Catalytic decomposition of methane is an environmentally attractive approach to
CO2-free hydrogen production. The decomposition of methane over carbon nanofibers was carried out in a fixed bed flow reactor. The objectives of this study are to demonstrate the activity of carbon nanofibers for methane decomposition in comparison with that of carbon black and to investigate the nature of active sites in the carbon catalysts. The catalytic activities of different carbon catalysts
were found in the following order: carbon nanofiber > HI-900L carbon black > N330 carbon black > non-catalyst. After investigating the surface area and mass of the carbon catalysts after methane decomposition, the nature of active sites was discused.
Interfacial Reaction between Molten Al Alloys and Titanium Matrix Composites
Authors: Sung Si Young , Choi Bong Jae , Lee Sang Hwa
Published: March 2009

The aim of this study is to investigate the applicability of titanium matrix composites
(TMCs) sleeve to Al alloys die-casting. Ti and 1.88 mass% B4C were prepared for the synthesis of 10 vol% (TiC+TiB) hybrid TMCs. In-situ synthesis and net-shape forming of TMCs were carried out in a vacuum induction melting furnace. The synthesized (TiC+TiB) TMCs were examined using scanning electron microscopy, an electron probe micro-analyzer, X-ray diffraction and transmission
electron microscopy. The resistance-ability of (TiC+TiB) TMCs to molten Al alloys attack was also examined. Their reactions were carried out in a furnace at 993 K for times varying from 0 to 1200 s. In the case of conventional sleeve material, H13 steel, there were severe interfacial reactions and erosion after 60 s. On the other hand, the resistance of (TiC+TiB) TMCs to interfacial reactions and erosion
by molten A380 alloy was significantly increased.
Fabrication of Ni Sulfides by Thermal Sulfidation
Authors: Nam Tae Hyun , Yu Cheol Am , Jung Dae Won , Cho Kwon Koo
Published: March 2009

The microstructure of Ni sulfides prepared by thermal sulfidation of pure Ni and their
dependence of fabrication parameters were investigated by means of scanning electron microscopy and X-ray diffractions. Sulfidation was made by isothermally annealing Ni with the sulfur in vacuum sealed glass ampoules at 673 K for 120 – 600s under the sulfur pressure of 100 and 220 kPa. The sulfide layers formed in the early stage were found to consist of spherical particles smaller than 0.5um, which were grown and agglomerated with increasing annealing temperature.
Thickness of sulfides developed on Ni substrate was found to increase with increasing annealing time and sulfur pressure. It was also found that compositions of dominant Ni sulfides changed with varying annealing time. At the initial stage, only Ni3S2 sulfide was formed on pure Ni, which was tightly bonded to Ni substrate. On increasing annealing time, NiS sulfide was formed. On further increasing annealing time, NiS1.97 sulfide was formed, which always coexisted with NiS
sulfide. A mechanism for sulfidation of Ni is proposed as follows:
3Ni + 2S Ni3S2, Ni3S2 +S NiS, NiS + S NiS1.97