bluuebunny/crossref_metadata_2025 huggingface dataset:
A New Architecture of LCD Driver of Rail-to-Rail Buffer with High Gain Wide Range
Authors: Lin Shih Han , Chen Shu Jung , Shen Chih Hsiung
Published: March 2010

A new modified CMOS buffer amplifier with rail-to-rail input and output range is proposed by TSMC 0.35μm 2P4M process at 3.3V supply. The technique adds dummy pairs to sense the common mode range of the input differential pair and adjusts the output current accordingly. The amplifier provides high gain for a wider range of output voltages. Design considerations for reducing the impact of the additional circuitry on the core are provided. The technique described can be adapted for use with traditional fully-differential rail-to-rail amplifiers, which performs 86.9dB ~92dB dc gain, 15 MHz unit-gain bandwidth, high driving ability with high slew rate under a 100pF capacitance and a 3kΩ series resistance loading. The simulation results indicate that the settling times of rising and falling edge are within 3.5μs. It is effective for a high resolution and high speed LCD driver.
Research on Characteristic Microstructure and Properties of Fe20Ni3Mn Alloy Induced by Laser Shock Processing
Authors: Chen Rui Fang , Hua Yin Qun , Ye Yun Xia
Published: March 2010

Fe20Ni3Mn alloy is treated by LSP. The hardness, residual stress and microstructure in the strengthened zone are studied. The results show that the hardness of the strengthened surface is increased about 15% and the surface compressive residual stress is reached about -469MPa. There exist martensite transformation and dislocation within 1mm depth from the specimen surface. Some martensitic structures have obvious trend of growth in steps. Specially, the twin crystals in martersite induced by LSP have important application.
Formation of Periodical Sub-Micron Sized Structures on Silicon by Interfered Nanosecond Laser Pulses
Authors: Hu Yong Xiang , Zhang Heng , Yao Zheng Qiang
Published: March 2010

Laser interference micro-structuring is a relatively efficient and cost-effective technique for fabricating periodical micro-nano-structuring surfaces. The direct fabrication of sub-micron sized dot array on silicon was performed by four interfering nanosecond laser beams with a diffractive beam splitter. The mechanism to form the dot array was analyzed and it was found that the obtained conical dot array had a negative shape of the interference pattern of four laser beams. A second-order peak between two first-order peaks also occurred due to the liquid-solid expansion.
Picosecond Pulsed Laser Induced Melting of Monocrystalline Copper: A Hybrid Simulation
Authors: Liu Xuan , Feng Ping
Published: March 2010

A hybrid method combing molecular dynamics and two-step radiation heating model is used to study the kinetics and microscopic mechanisms of picosecond laser melting of monocrystalline copper in stress confinement regime. The nonequilibrium processes of laser melting are simulated by classical MD method, and laser excitation as well as subsequent relaxation of the conduction band electrons are described continually by two-step radiation heating model. The mechanism responsible for melting of copper under picosecond laser pulse irradiation can be attributed to homogeneous nucleation of the liquid phase inside the solid region. The speed of stress wave is predicted to be 4400m/s equal to that of sound. The liquid and crystal regions are identified definitely in the atomic configurations by means of Local Order Parameter, in-plane structure and number density of atoms. Velocity-reducing technique is proved efficient in avoiding the influence of the reflected stress wave on melting process by comparing two models with velocity-reducing technique and free boundary condition at the bottom respectively.
Experimental Study on Csf/AZ91D Composite Using Extrusion Following Vacuum Infiltration Method
Authors: Guan Jun Tao , Qi Le Hua , Su Li Zheng , Liu Jian
Published: March 2010

10vol. % Csf/AZ91D composites were fabricated by extrusion following vacuum infiltration process with self-developed experimental device and measuring system. The relationships of load vs displacement during process and surface quality of composites at various extrusion temperatures were investigated. SEM microscope was used to observe the microstructure of fabricated composites. The experimental results showed that the extrusion process can be divided into three deformation stages. The extrusion temperature had a great influence on the maximum extrusion load. Based on proper infiltration parameters, a extruded bar with good surface quality was obtained at extrusion temperature of 420°C.
Research on Cladding Nickel on Copper Crystallizer Using Laser Metal Deposition Technique
Authors: Yang Guang , Liu Wei Jun , Wang Wei , Xing Fei , Tian Feng Jie , Qin Lan Yun
Published: March 2010

To increase the strength and erosion resistance of Copper Crystallizer, the system based on Laser Metal Deposition (LMD) process was proposed to clad nickel-based alloy on its surface. With the optimal processing parameters ascertained by large numbers of experiments, the crystallizer was clad nickel-based alloy. The morphology and the microstructures of the cladding layers and bonding interface were analyzed by energy dispersive spectrometer and scanning electronic microscopy. The result shows that the bonding interface realizes the metallurgic and tight bonding.
Simulative and Experimental Study on Laser Compound Forming of Plate
Authors: Huang Shu , Zhou Jian Zhong , Chen Yi Bin , Wang C.D. , Yang X.D. , Dai Y.C.
Published: March 2010

An appropriate finite element analytical model for laser compound forming (LCF) was established with ABAQUS code, and then some key technical issues in the simulations were studied and solved. Numerical simulation of LCF for V-shape was carried out to study bending deformation, residual stress distribution and micro-profile of AISI-1008 steel plate. After the corresponding experiments of LCF, the bending deformation, forming precision as well as the variation of surface integrities were mainly measured and analyzed. The results indicated that anticipated shape of V-plate could be precisely formed, meanwhile distribution of surface residual stress and surface qualities on plate were under good control.
Laser Cladding of an In Situ Synthesized TiB and TiC Reinforced Titanium Matrix Composite Coating on Ti6Al4V
Authors: Li Jun , Yu Zhi Shui , Wang Hui Ping
Published: March 2010

A titanium matrix composite coating reinforced by in situ synthesized TiB and TiC was deposited on Ti6Al4V by laser cladding. Microstructural analyses were made by means of X-ray Diffraction (XRD), Optical Microscopy (OM), Scanning Electron Microscopy (SEM) and Electron Probe Micro-Analysis (EPMA). The solidification process was also discussed in detail. The results show that the coating is composed of -Ti cellular dendrites and a eutectic in which a large number of needle-shaped TiB whiskers and a few equiaxial TiC particles are embedded. A thin dilution zone with a thickness of 50 m is observed at the interface, and consists of a few TiB and TiC and a large number of lamella grains in which a thin needle-shaped martensitic microstructure is exist. The solidification process could be divided into four stages: nucleation and growth of primary -Ti phase, precipitation of a binary eutectic -Ti+TiB, precipitation of a ternary eutectic -Ti+TiB+TiC and solid transformation from -Ti to -Ti.
Higher Precision Forming by Laser Peening under Pre-Bending Die
Authors: Zhang Xing Quan , He Guang De , Qi Xiao Li , Xie Neng Gang
Published: March 2010

The mechanism of laser peening forming was analyzed and the precision of laser peening forming was tested by experiments. In the experiments, the parameters of Nd: Glass laser were as following: the wavelength 1.06μm, the pulse duration 23 ns, the output power 32 J. The material of sample was aeronautic aluminum alloy LY12CZ, and its size was 150mm×90mm×3.5mm. The sample surface was coated with black paint and flowing water curtain served as overlay. The curvature radius of pre-bending die was 500mm. The shape of deformed plate after laser peening was measured. The experimental data indicate that the curvature radius of specimen after laser peening under elastic pre-bending state is 1872.13mm, and the maximum difference value in the R direction is 0.79mm. Comparing with the traditional forming processes, it is a high-precision forming technology.
Optimizing the RSW Process Quality of Auto-Body via the Taguchi Method and a Neural-Genetic Approach
Authors: Lin Hsuan Liang , Chou Chang Pin
Published: March 2010

This paper applies an integrated approach using the Taguchi method, neural network (NN) and genetic algorithm (GA) to optimize the tensile-shear strength of resistance spot welding (RSW) specimens in automotive industry. The proposed approach consists of two stages. First stage executes initial optimization via Taguchi method to construct a database for the NN. In second stage, a NN with Levenberg-Marquardt back-propagation (LMBP) algorithm is used to provide the nonlinear relationship between factors and the response. Then, a GA is applied to obtain the optimal factor settings. The experimental results showed that the tensile-shear strength of the optimal welding parameter via the proposed approach is better than apply Taguchi method only.
Theoretical Study on Stress State in Adhesive Layer of Single Lap Joint under Eccentric Tensile Load
Authors: Li Chun Liang , Zhou Jia
Published: March 2010

The paper put forward the way to calculate the bond stress state in adhesive layer of single lap joint under eccentric tensile load. And based on elastic theory to establish the calculation model of the stress state in adhesive layer of single lap joint under eccentric tensile load. According to the calculation model, the real stress state at the arbitrary point in adhesive layer can be calculated accurately. At the time, the resultes of the bond stress states of different length and width of single lap joint are analyzed and compared.
Microstructures and Mechanical Properties on Laser Welded Joints of Automotive High Strength Complex Phase Steel
Authors: Hu Lian Hai , Yan Qi , Huang Jian , Wu Yi Xiong
Published: March 2010

Reducing car’s weight has become an important goal for automobile industry. Laser welding of automotive high-strength steel plays a significant role in producing light weight cars. Experiments of CO2 high power laser welding of 1000MPa grade complex phase steels with a thickness of 3mm for automobile were performed using a 15 KW CO2 laser. The macrostructure and microstructure of the welded joint were examined by optical microscope. Mechanical properties of the welded joint, fusion zone and base metal were assessed by microhardness distribution across the welded joint, uniaxial tensile test and charpy V-notch impact test. Fractographs of the impact specimens were studied by scanning electron microscopy (SEM). It is found that the fusion zone has a higher toughness than that of the base metal and fusion line. The test results show good mechanical properties of laser welds that can meet the technical requirements for automobile Industry.
Investigation of UV Light Intensity Distribution of Integral Micro-Stereolithography System
Authors: Xu Guang Shen , Pan Huan , Ma Xun Ming , Luo Sheng , Qiu Rong Hua
Published: March 2010

The non-uniformity distribution of UV light intensity in the imaging plane of integral micro-Stereolithography (µSL) System will induces serious distortion of object in building process, and the building accuracy of the SL system can not be assured. To obtain uniformity distribution of UV light intensity, experimental investigations were performed to research the relationship of UV light intensity with position (x,y) in the imaging plane and gray-scale z of the pattern in the integral µSL System. Based on the experiment results, the model of UV light intensity was established with least squares method. According to the model, for a given point in the imaging plane of the µSL system, the UV light intensity can be changed with varying the gray-scale of the pattern. As a result, Uniformity UV light intensity distribution is obtained in the imaging plane, and the difference between maximum and minimum value of UV light intensity is 0.06µW/cm2. The uniformity UV light intensity distribution provides a foundation for building accurate microstructures with the µSL system.
Effect of Corrosion Pillowing on Mechanical Properties of Lap Joint
Authors: Yu Da Zhao , Chen Yue Liang , Gao Yong , Jia Zhong Hu , Liu Wen Lin
Published: March 2010

A mathematical model was developed to correlate the amplitude of the pillowing deformation of lap joints to the degree of corrosion inside the joint. Based on mathematical model, finite element techniques were used to determine the effect of pillowing in the stress in fuselage lap joints. The stress caused by the internal pressure and riveting process was taken into account, and the fuselage curvature was ignored. The results show that pillowing can significantly increase the stress in a lap joint for material loss below the detection limit of current nondestructive inspection techniques, thus increasing the risk of premature cracking. In addition, the analyses show that pillowing resulted in a stress gradient through the skin thickness, which suggest that semi-elliptical cracks with a high aspect ratio can form. In the last, the stress correction curves at the critical rivet hole were used in the AFGROW crack growth rate program to predict the residual life of corroded lap joint and the analytical results were close to available test date.
Characterization of 0.5 µm BiCMOS Gate Oxide Using Time Dependent Dielectric Breakdown Test
Authors: Wahab Mohd Zahrin A. , Jalar Azman , Abdullah Shahrum , Mamat Hazian
Published: March 2010

This paper presents Time Dependent Dielectric Breakdown (TDDB) testing of gate oxide on 0.5µm BiCMOS Technology. The gate oxide quality for the technology has been investigated and furthermore to qualify the whole set up of the foundry from the process, equipment, cleanroom control and raw material used to produce high quality gate oxide and hence good quality of BiCMOS devices. TDDB test is the most widely used testing to check the quality of gate oxide and in this paper the TDDB test done on MOS capacitors fabricated using 0.5 µm BiCMOS Technology. Seven consecutive qualification lots have been tested and the data shown that TDDB measurement is capable to differentiate between accepted wafer and rejected wafer. The data also shown that TDDB test was capable to characterise 0.5 µm BiCMOS gate oxide with higher yield and comparable with reference lot from other foundry fab.
FVM Simulation of Large Deformational Aluminum Extrusion Process and Die Bearing Optimization
Authors: Wang Rui
Published: March 2010

The mathematic model of three-dimensional aluminum profile extrusion processes using finite volume method (FVM) was established in this paper. Basic theory and key technologies of this model were researched and built. Non-orthogonal blocked structured girds were used to fit complex geometries. Volume of Fluid (VOF) scheme was used to capture the free surface of the deforming materials. A program AE-FVM was written according to the above theories and equations. A thin walled aluminum profile extrusion process was simulated and optimized using AE-FVM. The simulation results were also compared with that simulated by Deform-3D and SuperForge in the same conditions. The feasibility of the mathematic model built in this paper was demonstrated by the simulation results comparison.
Shaping Movement Analysis and Simulation of Ballscrew Manufactured by Cold Rolling
Authors: Cui Feng Kui , He Xuan Jing , Li Chun Mei , Li Yan , Han Zhi Ren
Published: March 2010

According to the kinematics theory of part surface forming motion and engagement principle, shaping movement of ballscrew manufactured by cold rolling has been investigated. The motion relationship and mathematical model of ballscrew have been built. By means of ADAMS and MATLAB the motion simulation and numerical calculation of cold rolling have been done. From analysis results, motion relationships between roller and workpiece and forming principle of cold rolling have been revealed. These studies will provide quantitative basis for technologic research of cold rolling and promote the study of ballscrew’s cold rolling forming mechanism.
Modeling and Analysis of NC Compliant Abrade Polishing for Surface of Revolution
Authors: Shi Yong Jie , Zheng Di , Zhan Jian Ming , Wang Long Shan
Published: March 2010

In this paper, a compliant tool was designed for abrade polishing parts with surface of revolution on general NC lathe. The tool can adapt itself automatically to the part’s surface. A magnetorheological torque servo driver (MRT) was developed to control independently the polishing force between the tool and the surface which determines the contact pressure and affects the polishing quality. The models of polishing force and contact pressure were established based on Hertz theory. The model of tool head posture was deduced. The impact of tool head posture and position on contact pressure was analyzed. The experiment results verified the validity of the compliant tool and models.
CAD/CAE System for Shaping Process of Three Dimensional Complicated Surfaces in Electrochemical Machining
Authors: Wang Lei
Published: March 2010

The paper presented a computer aided design and engineering (CAD/CAE) system that can be used to simulate and analyse three-dimensional complicated workpiece’s shaping process in electrochemical mahining. In the CAE model the finite element method was applied to analysis the electric-field distribution in inter-electrode gap. Factors affecting the electric-field distribution, such as flow factors and passivating electrolyte, are also taken into account by using database technology. The results of simulation and experiments showed that the system was of high precision.
Grinding Finishing Merging Electropolishing on Hole-Wall Surfaces
Authors: Pa Pai Shan
Published: March 2010

The current study presents a method for finishing hole-wall surfaces, superior to that obtainable by traditional boring, using a simultaneous grinding and electropolishing process. A specially designed finishing tool, that includes a nonconductive grinding wheel and an electrode is employed in the process. The form of the tool and the machining process are different from those used in electrochemical grinding (ECG). A high power electrical supply is not required with this design of finishing tool because the axial feed allows for the use of a smaller interactive area between the electrode and the hole wall surface. The experimental results show that a high current flow combined with a fast axial feed rate for the tool is an important advantage to the finishing process. The finishing effect is better with high rotational tool speeds because discharge of the electropolishing dregs and grinding cuttings becomes more efficient and this is also advantageous to the grinding finishing process. Pulsed direct current can slightly improve the electrochemical finishing effect, but machining takes longer and this raises costs. A small edge radius on the electrode also provides more than sufficient discharge and gives a better finish. We intend to make a complete evaluation of the processing parameter data so that the use of this method for hole-wall surface finishing may be extended in the future. The combined application of grinding and electropolishing is crucial to this method and the specially designed tool and the new finishing process are highly efficient and inexpensive.
Study on Optimization of Cathode’s Feeding Route in Flexible Feeding Electrochemical Machining
Authors: Wang Lei , Xu Zheng Yang
Published: March 2010

A new flexible feeding ECM machine has been presented in the paper. The rational optimization rules of cathode’s feeding are proposed. According to analysis of a three dimensinal complicated surface’s shaping process, the cathode’s feeding route is optimized. Instead of feeding at a constant angle the cathode in the paper can feed flexibly during the ECM process. Finally the analysis result of distribution of inter-electrode gap has shown that the optimized feeding route do help to improve the workpiece’s accuracy.
A New Manufacturing Method for a Screw-Threaded Fuel Filler Pipe
Authors: Kamei Nobuyuki , Watari Hisaki , Kawamura Youichi
Published: March 2010

The growing demand for lightweight products has been increased by the rapid development of automobiles in order to reduce fuel consumption. One of the keys to reduced fuel consumption is to utilize high-strength, light materials like stainless steel that are difficult to form due to their high strength.
This paper discusses the development of pressing technology that forms relatively high-strength stainless-steel pipe with surface screw threads. Our new press-forming process was tested to obtain accurate screw threads on stainless-steel pipe. A 3-D digitizer was used to measure the accuracy of pipes manufactured by the proposed pressing method. Our proposed press-forming method decreases pipe thickness more effectively than conventional roll-forming technology. The maximum decrease in material thickness produced by conventional roll forming was 40%. The maximum decrease in material thickness produced by our press-forming process was 20%.
Electrochemical Machining of the Turbulated Hole
Authors: Wang Ming Huan , Yao C.Y. , Zhang Qiao Fang , Peng Wei
Published: March 2010

Electrochemical machining (ECM) technology has the advantage of machining the workpiece with complex profile on the basis of electrolysis. In this study, turbulated holes with the rib’s shape of spiral and annular were processed by ECM by using the shaped cathodes. Experimental system was built which consists of electrolyte supply module, power supply unit and workpiece holding device. Machining experimentations were carried out on the built system. Analysis and discussions were done according to the experimental results. It indicated machining efficiency is high by using the shaped cathode. Machining error could be controlled within 10-20%.
Fast Polishing of Single Crystal Diamond
Authors: Chen Yi Qing , Zhang Liang Chi
Published: March 2010

This paper investigates the polishing of single crystal diamond using the dynamic friction method. It was found that by selecting a proper polishing pressure and sliding speed, a very high polishing rate at 10,300 µm/h (or 2.8 X 10-2 mg/s) with a high quality surface finish can be reached, which is hundreds times faster than the other polishing process reported in the literature. This method can be used to manufacture diamond products and to repair worn diamond components such as diamond cutting tools and diamond dressers for grinding wheels.
Optimum Geometrical Arrangement of Workpiece in the Ultrasonic Vibration Shoe Centerless Grinding
Authors: Fan Yu Feng , Zhu Yong Jian , Yin Shao Hui
Published: March 2010

This paper clarifies the influence of the geometrical arrangement of the workpiece on workpiece roundness in the ultrasonic elliptic-vibration shoe centerless grinding, and determines an optimum geometrical arrangement for minimizing the roundness error of the workpiece. The influences of the geometrical arrangements of the workpiece on workpiece roundness were investigated by computer simulation and practical grinding operations involving pin shaped workpieces. The experimental results agreed closely with those obtained by the simulation, the results of simulation and grinding tests indicated that the final roundness error of the workpiece after grinding reaches a minimum at a particular angle number (= + =7) for various values of the blade angle.
Surface Roughness Characteristics of Fine ELID Cross Grinding for Silicon Wafers
Authors: Chen Feng Jun , Yin Shao Hui , Ohmori Hitoshi , Katahira Kazutoshi
Published: March 2010

Silicon is widely used as the most important substrate material in integrated circuit and micro electronic devices field. Electrolytic in-process dressing (ELID) grinding technique is an effective grinding process especially for machining hard and brittle material. In this paper, using super fine abrasive wheel, sets of ELID cross grinding experiment were conducted for investigating the influences of various grinding conditions including grain sizes, rotation speeds of grinding wheel, rotation speeds of workpiece and ELID conditions on surface roughness during grinding silicon wafers. Surface roughness characteristics of fine ELID cross grinding for silicon wafers were discussed. In an optimized condition, surface roughness of 2.2 nm in Ra can be achieved by using #20000 wheel.
Finishing Clearance Research on Magnetic Abrasive Finishing
Authors: Chen Hong Ling , Li Wen Hui , Yang Sheng Qiang , Yang Shi Chun
Published: March 2010

As a kind of precise surface finishing technology, magnetic abrasive finishing has wide application, low cost, high efficiency, good effects, and other advantages. Finishing clearance is one main parameter affecting finishing effect and efficiency of magnetic abrasive finishing. Affecting rules of finishing clearance and filling volume are discussed by experiments, which provide basis for parameters selection and practical application of magnetic abrasive finishing.
Experimental Study on the Deformation of Oxide Scale and Friction during Hot Rolling of Stainless Steel 304L
Authors: Wei Dong Bin , Huang Jun Xia , Zhang Ai Wen , Jiang Zheng Yi , Tieu A. Kiet , Wu Fei , Shi Xu , Jiao Si Hai
Published: March 2010

Contact friction is of crucial importance for the accurate modelling, optimum design and control of industrial rolling processes. Hot rolling tests were carried out to investigate the deformation of oxide scale and friction during hot rolling of stainless steel 304L. The morphology of oxide scale layer and the surface roughness transfer under the conditions of hot rolling were obtained. The friction condition at the roll-strip interface was determined.
Study on Bio-Limited Forming Technology Based on Micro-Composite Sol-Gel Coating
Authors: Chen Bo , Zhang Wen Qiang , Lian Zhi Yang , Zhang De Yuan
Published: March 2010

Micro-composite sol-gel coating was introduced into bio-limited forming technology for the first time, and the feasibility of the micro-composite sol-gel coating on microorganism was verified. The composite coated microorganism was observed by using optical microscopy. The results showed that the micro-particles of carbonyl iron could remain being fixed on the surface of cells of spirulina platensis by sol-gel process after repeated washings and collections and by using second sol-gel process the micro structures of microorganism would be kept well after drying. The co-deposition mechanism of the composite coating was also discussed.
Study on the Conditions of Near-Field Acoustic Levitation
Authors: Liang Yan De , Ling Hong , Zhang Yuan
Published: March 2010

This paper establishes a near-field acoustic radiation pressure solving model applying with acoustics theory and derives an initial acoustic levitation calculating formula of rotundity objects. Combining with finite element and boundary element analysis, levitate conditions of levitated objects are calculated. This paper takes rectangular ultrasonic oscillator for example, testing and analyzing conditions of near-field acoustic levitation by using self-designed test equipments, the results are proved to be better.
Simulation of Particles Movement in Powder Mixed EDM
Authors: Wang Dong Guo
Published: March 2010

The particles dispersed in gap can increase the discharge stability and reduce discharge energy density in powder mixed EDM, which effectively improve the surface quality of machined workpieces. Concentration and distribution of particles computed by finite element methods in working conditions were simulated and corresponding experiments were done. The activities of particles in the discharge process were analyzed by experiments and theories. The results show particles have group effect in the gap and that the effect closely associates with particles concentration.
Heat Absorbing Rate in Laser Drilling of YG8 Alloy
Authors: Wang Xu Yue , Xu Wen Ji , Wang Lian Ji , Wang Jun , Liang Yan De
Published: March 2010

Based on a principle of laser drilling size and the roundness copied with respect of laser spatial mode, heat absorbing rate for laser drilling of YG8 is presented in theory and application. The mathematical models are then developed. The relationship of heat absorbing rate compared to the original absorbing rate is thus derived that is A = T +A0. It shows that heat absorbing rate to laser beam increases linearly with drilling temperature. The research outcome is used to optimize preheating process in which the novel method improves laser drilling precision from 0.03mm of primitive laser system to 0.01mm under the condition of heat absorbing.
Novel Jump Control for Debris Processes of Electrical Discharge Machining with Direct-Drive Spindle
Authors: Hsue Albert Wen Jeng , Chung Chih Hung
Published: March 2010

Owing to its low removal rate and debris ejection nature, EDM is a very slow machining process. A novel jump motion control for electrode in electrical discharge machining (EDM) equipped with dual linear motors (LmEDM) was proposed to release this debris efficiency point. The direct drive EDM and a novel pulse discriminator were developed. By introducing the discriminator to count effective discharge pulses, an EDM jump control was proposed. Experiments for verification of the EDM efficiency were conducted for 35 mm deep and thin EDM processes with 2 mm thin platelet. EDM efficiency of proposed jump control is verified to be four times over the traditional EDM.
Establishment and Application of Forming Limit Diagram of Multi-Gauge Laser Tailor-Welded Blanks
Authors: Chen Wei , Cheng S. , Ding Y. , Guo Y.Q. , Xue L.
Published: March 2010

The method for establishing the forming limit diagram (FLD) of multi-gauge high strength steel laser tailor-welded blanks (LTWB) is introduced based on analyzing the failure mechanism of multi-gauge LTWB. The Nakazima test is performed to generate the limit strain of multi-gauge high strength steel LTWB. By means of the ARGUS strain measuring system, the limit strain is measured and the FLD of LTWB is plotted subsequently. The FLD established by the Nakazima test is introduced into the FEA forming process as the failure criteria. Compared with the predicted result of the FLD of thinner metal, better correlation between the simulation and experimental results is indicated by adopting the FLD of LTWB as the necking criteria, which also reveals the validity and practicability of the FLD research method for multi-gauge high strength steel LTWB.
Error Compensation in One-Point Inclined-Axis Nanogrinding Mode for Small Aspheric Mould
Authors: Yin Shao Hui , Chen Feng Jun , Wang Yu , Fan Yu Feng , Zhu Yong Jian , Ohmori Hitoshi , Katahira Kazutoshi
Published: March 2010

A compensation method was proposed for correcting wheel setting error and residual form error in nanogrinding of axisymmetric surfaces. In this method, profile data from on-machine measurement were used to obtain the setting error of grinding wheel, as well as the normal residual form error. Compensation model of single-point inclined-axis grinding was built up for generating new compensation path. Grinding test of aspheric tungsten carbide mould was conducted to evaluate performances of the compensation method. A profile error of 182 nm (peak to valley) and average surface roughness of 1.71 nm were achieved. These results indicated that the form error compensation method may significantly improve form accuracy of ground surface.
One-Point Nano-Grinding for Micro-Aspherical Glass Lens Mould
Authors: Yin Shao Hui , Wang Yu , Fan Yu Feng , Zhu Yong Jian , Chen Feng Jun , Hu Tian , He Jian Bo
Published: March 2010

This paper reported an experimental study on ultra-precision grinding for micro aspherical lens mould. One-point grinding mode and inclined axis grinding mode are employed and investigated in grinding process. Grinding test of a micro-lens mould using form error compensation technique is conducted. The experimental results show that ground micro aspheric mould surfaces with form (PV) around 0.122 µm and a roughness (Ra) less than 2 nm is achieved successfully.
Design and Research on a Novel NEMS Accelerated Sensor Based on GaAs PHEMT
Authors: Zhang Bin Zhen , Jia Xiao Juan , Liu Jun , Xue Chen Yang , Hou Ting Ting
Published: March 2010

A novel nano electro mechanical system (NEMS) accelerated sensor which is based on piezo-resistive effect of GaAs/AlGaAs/InGaAs Pseudomorph-High Electron Mobility Transistor (PHEMT) has been designed and fabricated. The structures of sensor and sensitive element are described in this paper. The main process of Micro-machining is introduced in the text. The static press test has been performed and the testing results show that the NEMS accelerated sensor could sense exterior stress well. Then, a testing circuit is designed to detect the change of drain current under pressure. Through the vibration experiments of the sensor, the sensitivity has been discussed and given out. The conclusion that the sensitivity is maximizing in the saturation region can be got. And the measurement result shows that the sensor has good linearity and high sensitivity with 0.177mV/g in the saturation region.
Fabrication and Structure Measurement of the Double-Barrier Nano Film Resonant Tunneling Gyroscope
Authors: Du Kang , Wang Rui Rong , Li Meng Wei , Shi Yun Bo , Liu Jun
Published: March 2010

In this paper, a gyroscope with novel structure is designed and fabricated by the GaAs surface micromaching technology and GaAs bulk micromachining processes technology to achieve an integration of RTD and gyroscope structure. The structure and properties of RTD are tested by Transmission electron microscopy and Aglient 4156C semiconductor analyzer, and then the key parameters of gyroscope are measured by application of Scanning Electron Microscope. The effect of packaged gyroscope is tested by Polytec Micro-system analyzer. The problems in the fabrication process are analyzed and summarized, which have certain reference significance for the further study.
An Improved Thermal Type Microsensor with Thermal Isolation Microcracks
Authors: Cai Yun Zi , Shen Chih Hsiung , Chen Shu Jung
Published: March 2010

A new idea of improving complementary metal-oxide-semiconductor (CMOS) thermopile performance is introduced to reduce the thermal conductance by leading the microcracks into structure of thermopile, which greatly increases the heat flow barrier. A highly sensitive infrared detector requires a low thermal conductance to maximize the temperature change and signal induced by incident IR radiation. Several designs of infrared microsensors are proposed to study influential parameters from microcrack for improving performance of thermopile. To that end, by using some adequate designs of polysilicon architecture, we can greatly reduce the heat flow from the main stream without introducing further electric resistance, which is related with noise. Firstly we develop such a structure of thermopile with low thermal conductance and high performance by using CMOS compatible process which can be easily and exactly fabricated. The suspended structure of infrared sensors is used in this study to provide ideal, thermally isolated, structures for support of the thin film detector. We also simulate the heat flow of the new structures. The results show good match with our original idea.
New Method for Large-Scale Dimensional Metrology Using Laser Tracker System
Authors: Liu Wan Li , Wang Zhan Kui
Published: March 2010

Laser tracker system (LTS) is an advanced 3D coordinates measuring system for large size. It can measure large 3D coordinates with advantages of broad range, high speed and high accuracy. However, when the size of having been measured large-scale part (such as airplane and shipbuilding) is larger than the LTS measuring range, it can not measure all of the required features of components in one location, which profoundly affect the LTS measuring scope and accuracy. In order to solve measuring problem for large-scale parts, a new method of frog-jumping is proposed based on the principle of using LTS to measure more than three frog-jumping spheres under the new and old coordinate system. The corresponding mathematical model of frog-jumping is established. Intensive experimental studies have been made to check validity of proposed method; the results show that using this technology the measurement of large-scale parts all features is realized effectively under the required accuracy constraints.
Fabrication of Piezoelectric Thickness-Shear-Mode Acoustic Wave Sensing Device and its Application
Authors: Cao Zhong , Dai Yun Lin , Duan Zuo Shan , Zhang Ming Zhen , Xue Liang , Long Shu , Luo Dong Mei
Published: March 2010

The piezoelectric thickness-shear-mode (TSM) acoustic wave sensing device was fabricated by coating with a calixarene derivative on the surface of gold electrode of quartz crystal, then connecting with a transistor-transistor-logic (TTL) oscillator, a frequency counter and a computer. Among four coating materials, the compound of calixarene I was the most efficient active material for adsorption of carbinol molecule based on a host-guest recognition mechanism. In comparison with gas chromatography (GC) method, the calixarene based TSM device can be used for on-line determination of the poisonous carbinol vapor in the range of 0 ~ 3000 ppm around our living environment with good selectivity, reproducibility and high stability. The detection limit can be evaluated to be 1.41 ppm.
Evaluation of Measurement Uncertainty for High Precision Gear Involute Profile Measuring System
Authors: Ma Yong , Wang Kuo , Li Ke Hong , Wang Li Ding
Published: March 2010

This paper is concerned with an effective way to evaluate the measurement uncertainty for high precision gear involute profile measuring system in the gear testing centre Mahr891E which was improved both in numerical-electronic control system and mechanical parts . Optical system was used during the inspection process in this paper. The precision of involute profile measuring system in this gear testing centre was known to be available to test gear with high accuracy grade.
Exploration on Applying Non-Contact Photoelectric Detection Method for Double-Enveloping Hourglass Worm
Authors: Zhang Shu Yuan , Chen Xiao Jing , Yu Song Kun , Chen Ting Chen
Published: March 2010

According to the principle of processing, a non-contact photoelectric detection method for double-enveloping hourglass worm is investigated. The structure of the detection system is designed. It consists of solid-state image sensor CCD and light source. The parallel light source is installed on a sliding-board which is fixed on the rotary table. There is an inclination angular β between the parallel light source and the plane of the work table. The industrial CCD lens is mounted on the other side of the worm through a frame. The plane of the CCD is vertical to the parallel light source. Therefore CCD imaging is along with the direction of the generating process surface. By comparing the measured spiral tooth surface with the standard spiral tooth surface, the manufacturing error of worm can be calculated. Manufacturing accuracy of the worm can be obtained. Based on the four-axis CNC grinder, Non-contact photoelectric detection method is studied through preliminary experimental study. The experimental results indicate that this method is feasible in the precise detection of the double-enveloping hourglass worm.
Effect of La and La+Sr on Structure and Properties of ZL101A
Authors: Mi Guo Fa , Wang Ying , Wen Tao
Published: March 2010

After heat treatment, the structures and properties of ZL101A alloy with different La and La+Sr contents were studied. The results show that a significant modifying effect can be achieved in ZL101A in metal mould casting. The Si phase in the alloy becomes finer and the average alloy grain size is reduced from 3 mm to 1 mm with La addition 0.6%, which is mainly attributed to the enrichment of La at the eutectic front. The tensile strength and elongation increased with the increasing of La addition. However, excessive amount of La will have negative effects on the tensile strength and elongation. Mixed 0.2% La and 0.015% Sr results in further refined average grain down to 0.5mm, exhibiting improved strength and elongation properties.
On Determination of Geometric Damage Tensor
Authors: Liu Bin , Liu Quan Sheng , Wu Yue Xiu
Published: March 2010

It is common to use the damage mechanics to study the deformation of fractured rock mass. The geometric damage tensor is always used to describe the effect of distributed joints on mechanical properties of rock mass. The disadvantages of the traditional determination method about geometric damage is that the natural section of rock mass, mining section and the measurement section are not perpendicular to each other. In this paper, a method combining with the probability theory and field scale line method is adopted to determine the geometric damage tensor. This method is convenient and fast. The solution of initial damage in damage evolution equation can be settled with this method. An effective proof is provided for the later analysis of damage stress of fractured rock mass.
Hybrid Numerical-Optical Methods for Analysis of Mechanical Structures
Authors: Wang Cheng Zhi , Kujawińska Małgorzata , Dymny Grzegorz , Sitnik Robert
Published: March 2010

In conventional approach numerical and experimental solutions are independent and lack of interaction. Because each method has its own drawback, an interactive combination of numerical and experimental methods is proposed. An application of the hybrid method with Finite Element Method and optical metrology is illustrated, which demonstrates the viability of the feedback of experimental to numerical model, or numerical solutions to experimental setup and then improvement and adjustment of mathematical model and experimental setup.
Tower Type Sensors for Monitoring Corrosion Risk in Cover-Zone Concrete
Authors: Lu Shuang , Ba Heng Jing , Wang An Jian , Yang Ying Zi
Published: March 2010

In order to monitor corrosion risk in cover-zone concrete, an integrated tower type sensor (TTS) was developed to obtain the electrochemical parameters such as concrete resistance, macro-cell current and the corrosion potential of built-in electrodes. To obtain valid macro-cell current value, specialized short-circuit acquisition time equal to 30 s has been defined in present cement mortar. The results indicate that the macro-cell current increases and cement mortar resistance decreases meanwhile with the content of chloride ions increase in imported chloride cement mortar. The effective measurement of the macro-cell current and cement mortar resistance allows TTS to be used as a corrosion risk monitoring system in cover-zone concrete.
The Technique of Online Measurement and Data Processing for Aspheric Machining
Authors: He Liang Yu , Guo Yin Biao , Huang Hao , Wang Zhe , Wang Jian
Published: March 2010

In the traditional precision machining, it is easy to introduce positioning error because of the separation of the machining and the measurement. In order to solve this problem, an online measurement technique for aspheric grinding has been put forward. It measured the workpiece with sensor which was fixed to the high-precision machine tool. It processed data with the algorithm of Two-dimensional weighted average filtering and curve fitting based on Gauss-Newton and Levenberg-Marquardt least-square method. The experimental results indicated that the fitting residual error was less than 3×10-6 mm. In the grinding process, the measurement error was of the order of the magnitude of 10-3 mm. It can be concluded that the technique measures the surface exactly, and improves the machining accuracy effectively by providing accurate data for compensation.
Experimental Modal Analysis of Roller Gap Sensor Structure on Hot Rolling Mill
Authors: Ma Wei Jin , Wang Jun Yuan , Li Feng Lan , Xiong Shi Bo , Zeng Zhi Qiang , Liu Hong Qin
Published: March 2010

This research has carried on the vibration test to the roller gap displacement sensor structure by the one-point excitation and multi-point acceleration response. Based on the experimentation modal analysis theory, the modal parameters of the sensor structure have been extracted by the least square complex exponent (LSCE) method.The analysis results take the vital significance in establishing simulation model of the rolling mill depress system as well as carrying on the structure dynamics modification.
Development of Novel High Precision Angular Displacement Sensor
Authors: Hua Liang , Feng Hao , Gu Ju Ping
Published: March 2010

This study put forward a novel high precision digital angular displacement sensor. The mechanical structure design of the sensor was completed. The working principle of angular displacement sensor was analyzed in detail. The hardware and software design of the interface circuit of the sensor was completed and the performance of the sensor was analyzed. Compared with the traditional angular displacement sensors, the angular displacement sensor proposed in this paper has features of high precision, efficiency, explicit structure, better maintainability, low cost, wide measuring range, direction-judgement, no need to adjust zero and it has general application value in industry field.
Effects of Shot-Peening on Cr-Rare Earth-Boronizing at Low Temperature for Medium Carbon Steel
Authors: Xu Bin , Guo Ren Hong , Ma Zhong Quan , Gao Cai , Fan Xiao Hong
Published: March 2010

Effects of shot-peening on Cr-Rare earth-boronizing at 650°C for 4 – 8h for medium carbon steel are investigated in this paper. The value difference in boron diffusion activation energy between shot-peening and undeformation is calculated. The layer depth, microhardness and brittleness are also analyzed. The results show that the activation energy has a decrease of 5647.78 J/mol after shot-peening for 1.5h, and the layer depth increases with prolonged shot-peening time. The layer can also retain its high hardness with low brittleness. The analysis indicates that shot-peening can provide a large number of crystal lattice defects that facilitates boron diffusion in the steel, and the low temperature is apt to remain high dislocation density.
Surface Roughness Pattern Measurement of Tensile Specimen by Using Digital Holography
Authors: Kim Kyeong Suk , Hong Dong Pyo , Choi Man Yong , Jung Hyun Chul , Kim Dong Soo , La Sung Won , Chang Ho Seob
Published: March 2010

The objective of this paper is measurement of the surface roughness of tensile specimens under different tensile speed. In the test, the tensile specimens were loaded by tensile testing machine. The roughness of the surfaces was measured by digital holographic interferometric system (DHI). From the results, it was confirmed that DHI could measure the roughness of the various types of the specimen surface. In this paper, as the tensile speed was faster, the roughness of specimen surface was smaller.
The Finite Element Analysis of the End Anchorage under Larger Prestressing Load in Rehabilitation Engineering
Authors: Huang Fei Xin , Jiang Hai Bo , Wei Chun Gen , Ouyang Shi Wu , Long Xiang
Published: March 2010

Anchorages are the most important structure in the bridge’s rehabilitation engineering under external prestressing load, whose stress distribution is complex, it is necessary to carry out a detailed and careful structure analysis of anchorages. The inspection and strengthening design of an extra-large Bridge in Dongpu of Guangzhou City was taken for the background in the paper, the longitudinal stress, transverse stress and vertical stress of the end anchorage were given before and after adding concrete block, through finite element analysis of the end anchorage under larger prestressing load and the results of calculation of the anchorage were analyzed, it was showed that the strengthened effect of the end anchorage had been very obvious after concrete block was added. At the same time it was found that there were still some deficiencies on the end anchorage after concrete was added and the suggestions of the local strengthening of the end anchorage were proposed. It is helpful and referenced for the design of similar anchorage.