bluuebunny/crossref_metadata_2025 huggingface dataset:
Advance in Chip Breaking Detection System by Monitoring of Cutting Temperature
Authors: Tangjitsitcharoen Somkiat
Published: November 2012

This research presents the chip breaking detection system by monitoring the cutting temperature during the in-process turning. The effects of cutting parameters on the cutting temperature and the chip formation are investigated. The in-process monitoring of chip formation is developed to detect the continuous chip, the mixed chip and the broken chip by utilizing the ratio of the maximum variance of the dynamic cutting temperature to the average variance of the dynamic cutting temperature. The broken chip formation is required for the reliable turning operation. The new algorithm is proposed to obtain the broken chip by changing the cutting conditions during the cutting process referring to the cutting temperature. It has been proved by series of cutting experiments that the broken chip can be well identified by the proposed method.
Design and Performance Assessment of a 5-Axis Ultra-Precision Micro-Milling Machine
Authors: Huo De Hong , Cheng Kai , Ding Hui
Published: November 2012

This paper presents the development and performance assessment of a novel 5-axis ultra-precision micro-milling machine (UltraMill) which enables ultra-precision micromachining of high precision 3D miniature components and micro features. An integrated design approach with motion accuracy, dynamic stiffness and thermal stability prioritized has been proposed and applied to analyze and optimize key machine components and their integration. Direct drives and aerostatic bearings with the squeeze oil-film damper are employed in the micro-milling machine throughout, which offers higher motion accuracy, improved dynamics and loading capacity. Micro-milling trials were performed on OFHC copper using tungsten carbide, CVD diamond and single crystal diamond micro tools. Both micro featured profiles and micro machined surfaces were measured to validate the proposed machine specifications and performance.
Numerical Simulations of the Influence of the Tool Geometric Parameters on Cutting Forces and Temperatures in High-Speed Machining of Ti6Al4V
Authors: Du Mao Hua , Wang Shen Song , Li Ai Zhen
Published: November 2012

In the contrast study of establishing the frictional models in finite element (FE) simulations of high-speed machining Ti6Al4V in this work, FE predictions from the simulation are greatly influenced by frictional coefficient μ, which shows the predicted force at the speed of 166m/min is much closer to the experimentally measured one when μ=0.2. In order to investigate the tool wear in high-speed cutting to prolong the tool life and reduce the tool cost, the influences of the tool geometric parameters including the rake angle γo, clearance angle αo and cutting edge radius rε on the chip formation, on the cutting forces and on the cutting temperatures are numerically simulated under the given cutting conditions, then the general rule of the selection of γo, αo and rε is presented accordingly. In the meantime, the average cutting forces and temperatures are obtained under different simulation conditions, which are the basis of further study on the relationship between the tool geometric parameters and cutting forces together with temperatures to obtain the proper tool geometric parameters for simultaneously controlling both cutting forces and temperatures to their proper values in high-speed machining in practice.
Research on the Molding Technology of Bonded NdFeB Magnets
Authors: Qin Wan Zhong , He Jie , Yao Ling Yi
Published: November 2012

For the composite powders with different NdFeB powder content , the effects of processing parameters including injection temperature, injection pressure, holding pressure and injection velocity on the sizes and properties of injection molded bonded NdFeB magnet were investigated, and the reasons of effects were also analyzed. The results show that changes in injection parameters can influence the size, density, mechanical properties and magnetic properties of bonded NdFeB magnets, and has strong influence regularity. The injection temperature and injection pressure have the greatest impact on the performance. On the basis of research, the injection molding bonded NdFeB magnet with high performance is obtained with magnetic properties Br=0.539T, Hcb=345.37kA/m, Hci=681.02kA/m, (BH)max=47.37kJ/m3 and density 5.07g/cm3 respectively.
Processing of Grinder Plate with Bone Chips Removal Facilities Based on CAD/CAM
Authors: Li Shi Long , Zhao Xian Feng
Published: November 2012

Rotary meat grinders with bone chip removal facilities are advanced meat mincing machinery, characterized by undesirable hard-particle separation from ground meat during grinding operations. The grinder plate with an involute spiral groove to facilitate removal of hard particles is developed. The perforated plate with bone chips removal facilities has a unique design including catcher groove, bone-collection chamber and bone-removal passage. Its 3D modeling in Pro/E software, machining process planning, milling path optimization, simulation based on MasterCAM and compiling post program were introduced and verified. The results indicated that adoption of CAD/CAM offers firms the potential to pursue new innovative strategies.
Experimental Study of Ultrasonic Vibration Drilling Ceramic Material
Authors: Zou Ke Rang , Wang Chao , Zhang Liao Yuan
Published: November 2012

Abstract According to the high frequency vibration of the diamond tool and feed motion of the machine tool, the kinematic model of ultrasonic vibration machining was established by superposition principle. Its motion law was analyzed in theory. The experiments on the drilling force, the impact of load on the processing efficiency, and the surface quality of the workpiece with ultrasonic vibration drilling and traditional machining were carried out on the improved ultrasonic vibration drilling machine by way of drilling the ceramic material.
Study on the Two-Side Direction Burr in Grinding-Hardening Machine Based on Orthogonal Experimental Method
Authors: Liu Ju Dong , Yuan Wei , Xiong Jin Kui , Xu Zhi Long , Huang Song Wei
Published: November 2012

Based on the orthogonal experiment, this paper studied the influences of depth of cut ap, table speed vw and grinding method gm on the two-side direction burr in grinding-hardening machine. The results show that, with thermal-force coupling effect induced in the grinding-hardening machine, the metal in the workpiece’s surface flowed to two-side direction of the workpiece that without any constraint and leaded to the burr’s formation. The depth of cut ap and grinding method gm are significant factors that affected the size of two-side direction burr, and the significant order are as follows: depth of cut ap> grinding method gm > table speed vw >interaction av. With the increasing of depth of cut ap or the grinding trip, the max size of the two-side direction burr increased gradually; and with the raising of table speed vw, the max size decreased firstly and then increased. In actual application, it should adopted the grinding parameters ap＝0.2mm，vw＝0.6m/min and up-down grinding to improve the quality of grinding-hardening and reduce the size of the burr.
Effect of Charge Action on the Annular Molten Metal of Spray Forming
Authors: Qu Ying Dong , Jiang Chong , Li Xiao Hong , Su Rui Ming , Li Rong De
Published: November 2012

This paper described the effect of hollow jet atomization technology, under charge action, according to the spray forming process, to improve the quality of atomization. In order to deeply study the charge action on the annular molten metal of spray forming process, this paper analyzed theoretically quantity of electric charge of the annular molten metal and the surface tension of atomization droplets. The results show that the quantity of electric charge increases with the increasing of charging voltage. Under the same conditions, the hollow annular metal liquid charge is always greater than the solid cylindrical molten metal charge, but the surface tension is less than the solid molten metal. As the quantity of electric charge reduce the surface tension of the droplet, the power of atomization increases relatively. It means that the atomization quality of annular molten metal will be better than the solid cylindrical molten metal. By comparison, the structure under charge action is fine and homogeneous after experiment.
Shape Forming of Alumina by Step Pressure-Vacuum Hybrid Slip Casting
Authors: Cho Kyeong Sik , Kim Jae , Lee Seung Yeul , Oh Joong Pyo , Park Seung Il
Published: November 2012

Conventional methods for preparing ceramic bodies, such as cold isostatic pressing, gypsum-mold slip casting, and filter pressing are not completely suitable for fabricating large and thick ceramic plates, because of disadvantages such as the high cost of equipment, formation of density gradient, and differential shrinkage during drying. These problems could be avoided by employing step pressure-vacuum hybrid slip casting in which consolidation occurs not only by the compression of the slip in casting room, but also by vacuum sucking of the dispersion medium (water) around the mold. This method enabled us to fabricate a 110 × 110 × 20 mm alumina plate without cracks and with homogenous density, and the possibility of extending the method to fabricate other ceramic products appears to be promising.
Experimental Evaluation of Surface Roughness in Orthogonal Micro-Milling Processes
Authors: Wu Ji Hua
Published: November 2012

Surface roughness plays a critical role in evaluating and measuring the surface quality of a machined product. Two workpiece materials have been investigated by experimental approach in order to gain a better understanding of their influence on the obtained surface roughness in the micro-milling processes. The experimental results show that: surface topography is completely different for different materials at the same cutting speed and feed rate; surface roughness increases with an increase of material grain size. Surface roughness decreases to a lowest value, and then increases with an increase of the feed rate. A new surface model to illustrate the influence of material and uncut chip thickness was developed. The model has been experimentally validated and shows more promising results than Weule’s model.
Study of Bulging-Pressing Compound-Deforming Automobile Axle Housing with a Common Press
Authors: Wang Lian Dong , Cui Ya Ping , Yang Dong Feng
Published: November 2012

The conventional hydroforming process for automobile axle housing needs a large-tonnage press and has the drawback of the dome part being apt to burst due to the large thinning. A new forming technology, bulging-pressing compound-deforming for automobile axle housing, is proposed, which is suitable for the large variable-diameter tube parts with special-shaped cross-sections. The initial tube is made into the axisymmetric peforming tube after the ends necked and the middle hydroformed, and which then is pressed into the axle housing sample by the dies. For a small automobile axle housing, the process tryout and the pressing dies were designed, and the axle housing samples were successfully produced with a common press. Compare with the conventional hydroforming process, the forming corner radiuses of present samples are smaller and the internal pressure decreased 60%. The results show that the process has the advantages of good corner-filling ability and low internal hydraulic pressure.
Effect of Doping Transition Metal Ions on Photocatalysis of TiO2 Nanowires
Authors: Tian Yu Ming , Zhao Yuan Yuan , Gong Chang Wei , Chai Yue Sheng
Published: November 2012

In order to restrain the recombination of electron-hole pairs of photocatalysis and induce the absorption spectra to shift to the visible region, TiO2 nanowire arrays doped with different transition metal ions were prepared by sol-electrophoresis deposition method. The photocatalytic activities of all doped nanowire arrays (M/TiO2) were measured under visible light. Transition metal ions (Fe3+, Zn2+, Cr3+ and Cu2+) were chosen as doping ions. The best doping content of each ion was found via photocatalytic degradation of methyl orange solution under visible light, there are 0.5 wt% Fe3+，1.0 wt% Zn2+，0.5 wt% Cr3+ and 0.25 wt% Cu2+ respectively. Under the best doping content of each ion for M/TiO2 nano-arrays, the photocatalytic activities are Fe>Zn>Cu>Cr. The effect mechanisms are discussed from different views of doped semiconductor and surface oxygen absorption.
Microstructure and Recrystallization Behavior of an as-Extruded PM Nickel-Base Superalloy
Authors: Zhang Min Cong , Wang Shu Yun , Li Jin Dong
Published: November 2012

The powder metallurgy (PM) nickel-base superalloy GH720 was extruded at 1100°C and the as-extruded samples were treated at 1110°C during 10min, 20min and 30min apart. The microstructure and recrystallization behavior of as-extruded alloy GH720 were discussed. The results indicate that there are two different types of γ' phases: primary γ' phase is mainly distributed on the grain boundary with an average size ranging from 0.3 to 0.5μm and dissolves partially at 1110°C during 30min, whereas the secondary γ' phase is distributed inside the grains with an average size of 50nm and dissolves largely at 1110°C during 30min. Recrystallization mechanism is subgrain nucleation when as-extruded GH720 is treated at 1110°C at which a lot of γ' phase exist. γ' phase inhibits growth of recrystallized grain availably and the uniform, fine and equiaxed grains in GH720 were formed during the extrusion and following heat treatment process.
An Investigation of Heat Affected Zone of Round Steel Rods Welded by Friction Welding
Authors: Thinvongpituk Chawalit , Arayangkun Surasing
Published: November 2012

Friction welding is a welding technique that has been studied and developed continuously. This is due to its advantages, such as it provides high quality of joint, high strength of joint. It can make welded zone through the whole section without bubble. However, there is heat generated in the welding process that can change the phase of materials. Hence, the hardness and strength of joint are affected. This paper is aimed to investigate the microstructure at the joint, which is called heat affected zone. The experiment was conducted with a number of steel rods of 10 mm. diameter. The welded specimens were tested for strength, hardness and microstructure. The temperature gradient of specimen under welding process was also recorded. It was revealed that the strength of welded element is higher but the hardness is lower. The photo of thermo scan revealed that heat is generated around the lip of interface, resulting high temperature in heat affected zone. This causes some change in microstructure composition as well as joint property.
The Research on the Quality of the Cutting Mouth for Laser Blanking
Authors: Zhang Li Jun , Zhang Zhong Mei
Published: November 2012

This thesis introduces the concept of laser blanking and analysis the hardness differences, the ripple, the dross through experiments. Through this we get know the factors and data changes which are affecting the quality of laser blanking cutting. The results show that the cutting quality, such as the laser power, material thickness, cutting speed, focus position, air pressure and the shape parameter fluctuations, is very sensitive to the process conditions. Any factor changes will have an effect on the cutting quality.
Study on Eliminating the Effect of Bending Moment in Torque Measurement
Authors: Jiang Qing Hai , Sun Yu , Xu Xiao Yong
Published: November 2012

The function characteristics of bending moment and torque were analyzed based on the principle of torque measurement and the adverse effect of bending moment to torque measurement was proved theoretically. By distributing the positions of resistance strain gauge on the transmission shaft and the relative positions in the bridge, an effective method of eliminating the adverse effect of bending moment was proposed base on the principle of superposition and counterbalance in the bridge, and the potential errors were analyzed and corrected. Then the proposed method was applied in measuring the torque of a motor shaft. The result shows that the effect of bending moment has been eliminated, and this method is feasible and effective.
Test of Metal Material Fracture Toughness by Finite Element Simulation and Moire Interferometry
Authors: Wu Yong Dong , Guo Yuan Shuai , Li He
Published: November 2012

In this paper,Fracture Toughness of TC11 alloy material at normal temperature is found out by Finite Element Simulation and Moire Interferometry. The feasibility and veracity of Finite Element Simulation is shown by comparing numerical and experimental results.
A Novel Triangle Element Formulation for Static Analysis of Solids
Authors: Chen Hui Hui , Jia Cheng
Published: November 2012

A new formulation of triangle element is developed. Based on the concept of unsymmetric finite element formulation, classical linear triangle shape functions are used as test functions, and FE-LSPIM TRI3 element shape functions are used as trial functions. The former is fulfill the requirements of intra-element and inter-element continuity in displacement field, and the latter is a good alternative for requirements of completeness in displacement field. Typical test problems for static solids are analyzed. The results show that the proposed element has good accuracy, and is superior to classical linear triangle element and isoparametric quad element.
The Prediction of the Mechanical Properties of Gray Cast Iron Based on the Anatomy Experiment of the Engine Cylinder Head
Authors: Zhou Zhou , Zhou Jian Xin , Yin Ya Jun , Shen Xu , Sun Liang
Published: November 2012

In order to predict the mechanical property during the actual production of gray cast iron, to qualify the casting for the requirement of mechanical property and to control the cost, in this paper a series of anatomy and mechanical property experiments are conducted based on the automobile engine cylinder head processed through the actual production. The actual Brinell Hardness (HB) and the pouring parameters of the cast iron are acquired through the experiment. According to the pouring parameters, the cooling curve is obtained through the Inte CAST software simulation and the cooling rate is also calculated. Based on the existing property prediction model, the Brinell Hardness property prediction model of the engine cylinder head is deduced. The prediction results conform well to the actual data results.
Application of Tetragonal Nano-Zirconia in Ceramic Teeth
Authors: Wang Qiang , Zhang Ming Zhu , Sun Ling Na , Hu Chang Wen , Cao Chuanbao
Published: November 2012

Nano-zirconia (Nano-ZrO2) has good natural color, high strength, high toughness, high chemical stability, excellent corrosion resistance and resistant to chemical attack and microbial erosion particularly, which is one of the biocompatible inert materials and is widely used in biology, medicine and other fields. There are cubic (c-ZrO2), tetragonal (t-ZrO2) and monoclinic (m-ZrO2) phase three different crystal structures of zirconia (ZrO2) in normal atmosphere and different temperatures. In the three different crystal structures, t-ZrO2 has the best performance for ceramic dental materials. However, ZrO2 is usually in the form of m-ZrO2 at room temperature. So to study the synthesis and stabilization methods at room temperature of nano-t-ZrO2 is very important in scientific significance and application prospects.
Mechanical Properties of AlMgB14 Prepared by Field-Activated, Pressure-Assisted Synthesis Process
Authors: Yan Jian Xin , Liu Wen , Wen Wei Zhong , Li Ji Bing
Published: November 2012

Mechanical alloying(MA) and field activated and pressure assisted synthesis(FAPAS) combining the method of in-situ synthesis were used for the preparing ultra-hard, super-abrasive AlMgB14 metallic ceramic. AlMgB14 was performed at 1500°C under a pressure of 60 MPa from the elemental constituents (aluminium, magnesium and boron (vacuum annealed 1500°C)). The sample was examined by SEM, EDS and XRD. The products contained uniform AlMgB14. The hardness of AlMgB14 prepared under these conditions is 27.2-32.5GPa, the average density is 2.62g/cm3 and the fracture toughness is 3MPam1/2.These values are in correspond to the hardness of AlMgB14 prepared by mechanical alloying/hot uniaxial pressing (28-35GPa). Analysis of the mechanisms of fracture,the fracture surface of AlMgB14 sintered at 1500°C is of transgranularfracture. A new approach is brought forward by the mechanical alloying assisted FAPAS process (MA-FAPAS) to have synthesized AlMgB14 with fast heating-up, efficiency, energy saving and high yield.
Prediction of Surface Fracture of 6061 Al Processed by Equal-Channel Angular Pressing
Authors: Zhou Qing , Chen Wen Jie , Xu Jun , Duan Yu Peng
Published: November 2012

Improving the efficiency of equal-channel angular pressing (ECAP) necessitates predicting the location of fracture and the number of ECAP passes required when fracture is formed. However, the damage mechanism in ECAP-processed materials remains insufficiently understood. Surface fracture formation during the ECAP of 6061 Al-T4 alloy was investigated by finite element simulation and experimentation. The simulation of damage distribution in the sample was based on the Cockcroft and Latham criterion. Fracture formed in the upper and lower surfaces of the sample, a finding that is in good agreement with the simulation results for damage factor. A critical damage factor, calculated from the experimental data, accurately predicted the number of ECAP passes required when surface fracture is formed. Tensile stress was caused by various strain rates in different parts of the sample cross-section as the sample was pressed through the bend channel; this stress was the main driver of damage formation.
Unsteady Numerical Simulation and Ground Tests of a Tailplane Electrothermal De-Icing System
Authors: Zhao Yong
Published: November 2012

For the electrothermal de-icing system of an aircraft tailplane, firstly, an unsteady numerical simulation was conducted for understanding of the heating of the skin. Then ground tests in dry air conditions for the electrothermal de-icing system were designed and conducted, where the ambient temperatures were under the freezing point. The results of theoretical calculation show that, under the given conditions, the highest surface temperature of the tailplane electrothermal de-icing system can reach 67°Cand the lowest surface temperature is close to the ambient temperature. Starting from the third heating cycle, the fluctuation of the surface temperature reaches a stationary cycle. The ground tests show that the designed electrothermal de-icing system can meet the design requirements. It takes less than 25 seconds to raise the surface temperature from -20°C to 0°C. The peak surface temperature in the periodical heating cycles is below 80°C, which is lower than the tolerance limit of the skin material.
Numerical Predicts of Flow and Heat Transfer in Joule-Heated Rectangular Pool
Authors: Zhang Xiao Hui , Chen Wei
Published: November 2012

Based on the Joule heating nuclear waste treatment technology, a series of numerical simulations have been studied to predict transient flow and heat transfer.The physical model is a rectangular cavity filled with fluid, the direct current contributes heat for heating the process medium by a pair of plate electrodes. For Pr=1 fluid, the thermally driven stable convection and the electromagnetically driven stable flow can be observed respectively or both gravitationally and electromagnetically driven stable convection exhibit. The threshold Hartmann number for the flow transition from an asymmetric 2 cells steady flow to a steady non- asymmetric state 1 roll flow is 159.687, where the Nusselt number exhibits a minimum value. And the second transition from non- asymmetric state 1 roll flow to a steady asymmetric 2 rolls flow is fixed at 178.88 with Ra=1.0×105. The results can provide some guidelines for conceptual thermal control for Joule heated ceramic melter technology.
Design and Manufacturing of a Constant Volume Test Combustion Chamber for Jet and Flame Visualization of CNG Direct Injection
Authors: Hajialimohammadi Alireza , Ahmadisoleymani Saeed , Abdullah Amir , Asgari Omid , Rezai Foad
Published: November 2012

Constant volume transparent test combustion chambers are extensively used for investigating injection and fuel burning properties of various combustion engines. Their configuration depends on the engine type and the research purpose. Material of components, shape and dimensions of the chamber and its parts, ease of use, accessibility, sealing and safety of the assembly are the parameters needed to be considered in designing the test cell. This paper explains, structural design of a test combustion chamber and its optical windows using finite element analysis of ANSYS 12.0 software for bearing high pressure variations and thermal shocks of combustion. It was designed for conducting CNG direct injection study on direct injection SI CNG engines for maximum design pressure of 100 bars. Optical diagnostic methods and high speed photography through quartz windows are used for the jet and flame developments. Satisfactory test results of the fabricated system proved that the finite element method can successfully be employed for design of such a system.
The Application for Underwater Special Monitoring Equipment Based on the PELCO-D Protocol
Authors: Yu Xing , Liu Jing Biao , Sheng Qing Hua
Published: November 2012

Aiming at integrating Tritech Company’s Typhoon color zoom camera and Kongsberg Company’s underwater pan and tilt unit OE10-102 to build the underwater monitoring system, this paper designs a method, which uses STM32F103C8 as the core chip to design a protocol converter. The protocol converter could receives and analyses the PELCO-D data frames from RS-485 bus, and then produces corresponding commands to control the cameras and rotator units. Besides, this paper provides a new online program update method based on RS-485 channel, which could make full use of the existing 485 channel to complete user application program updating for the protocol converter without disassembling the deceives. Practice has proved that the methods mentioned are practical and stable.
Investigation of Machining Characteristics of Ultrasonic Vibration Assisted ECM
Authors: Kurogi Sosuke , Natsu Wataru , Yu Zu Yuan
Published: November 2012

In ECM process, insulating by-products exists in the inter-electrode area. These by-products disturb the current flow between the tool and workpiece electrodes, and thus affect the machining accuracy. As one of the ways to remove the by-products, a method was proposed to apply ultrasonic vibration to the tool electrode. However, the influence of the electrolyte concentration and the effect of ultrasonic vibration on the machining characteristics of the WC alloy have not been investigated yet. Therefore in this study, these influences were experimentally investigated. It was found that the machining accuracy is increased by using the low concentration electrolyte. Also, machining of the tungsten carbide (WC) alloy when applying the ultrasonic vibration to the tool electrode becomes possible.
Hydrodynamic Noise and Radiated Mechanism of 3D Cavity
Authors: Wang Yu , Li Bai Zhou
Published: November 2012

The flow past 3D rigid cavity is a common structure on the surface of the underwater vehicle. The hydrodynamic noise generated by the structure has attracted considerable attention in recent years. Based on LES-Lighthill equivalent sources method, a 3D cavity is analyzed in this paper, when the Mach number is 0.0048. The hydrodynamic noise and the radiated mechanism of 3D cavity are investigated from the correlation between fluctuating pressure and frequency, the near-field sound pressure intensity, and the propagation directivity. It is found that the hydrodynamic noise is supported by the low frequency range, and fluctuating pressure of the trailing-edge is the largest, which is the main dipole source.
The Study on the Ultrasonic Testing and Defects in Quantitative Analysis for the Scroll-Type Profile
Authors: Wang Yanying , Guan Hao , Huang Zhi Gang
Published: November 2012

The model of ultrasonic testing system kinematics was established, and ultrasonic testing of the scroll-type profile was come out. Based on reverse engineering (RE) techniques, the 3D model of actual parts was reconstruction. And then, the semitrailer 3D image about the position of lacuna was revealed in the model.Consequently the characteristics of lacuna were selected according to class. In finally, the rank identification method was adapted to recognize lacuna simply. Once this method is applied successfully in practice, the product quality and reliability of scroll compressor is improved, and the theoretical and practical support for full inspection of the product is provided.
Preparation and Characterization Nano-Cellulose and its Surface Modification by Silane Coupling Agent
Authors: Gao Tian Ming , Huang Mao Fang , Li Pu Wang , Han Zhi Ping , Xie Rui Hong , Chen Hong Lian
Published: November 2012

Pineapple leaf fiber (PALF) was pretreated by sodium hydroxide, and hydrolyzed by sulfuric acid to obtained nano-cellulose (NC). The SEM showed that size of NC is 30-50nm. Bis[3-(triethoxysilyl)propyl]tetrasulfide (Si-69) was employed to sueface modificate the NC. The results of characterization of particle size, zeta potential, FTIR and contact angle illuminated that particle size of surface modified NC was smaller than NC and zeta potential of -75.8mV was lower than NC’s. The hydrophobicity of surface modifiedNC has been improved.
A New Detection Way for Single- Phase to Ground Fault Based on Energy Function Intergral and Wavelet Packets
Authors: Liu Yang , Chen Zhang Bao , Ye Lin
Published: November 2012

In order to find new fault line selection method of single-phase distribution network, First parallel resistance in the neutral point in order to increase the transient component of the fault line, obtained the line energy after the failure through the integral transform , initially selected probable fault lines , on this basis, decompose all the transient zero sequence currents in every line by separation based on nicer separate frequency characteristic of wavelet packets, to accurately determine the greatest fault line by the characteristic that the value of second singular point generated by zero sequence current is maximum and its polarity is opposite to the other normal lines, simulation results show the effectiveness and correctness of the method. So the method for detection of the fault line based on wavelet packets and the compare of energy is new and effective.
Wind Speed Forecasting Based on Variable Weight Combination Model of Neural Network and Grey Model
Authors: Zhang Jian , Tan Lun Nong
Published: November 2012

The wind speed forecasting accuracy of artificial neural network(ANN) and grey model(GM) is poorly satisfied. Thus, we proposed a new variable weight combined (VWC) model, which was based on the ANN and GM, to improve the wind speed forecasting accuracy. VWC used weighting coefficient of different time to fit the two single models. The forecasting accuracy of VWC is higher than either of the two single models, and is also higher than the unchanged weight combination(UWC) model. Our data show a new method for wind speed forecasting and the reduction of auxiliary service costs of wind farms.
A Six-Probe Scanning Method for Guide Rail Straightness Measurement
Authors: Yang Jiao Jiao , Chen Xin , Ding Guo Qing , Lei Li Hua , Li Yuan
Published: November 2012

Straightness error is the main profile error of guide rail. This paper studies a scanning six-probe system for measuring straightness of two guide rails. The system does not use angle sensors and consists of two probe-units, each having three displacement sensors. The two probe-units are moved by a scanning stage to scan the surface of two guide rails, then they are rotated 180 and scan guide rails again after the first scanning. The zero-differences of two probe-units before and after probe-units being rotated, as well as the straightness of the guide rails, can be accurately evaluated from the outputs of the displacement sensors in two scanning process. The effectiveness of this method is confirmed by computer simulation and experimental results in the case of two probe-units having different zero-differences before and after probe-units being rotated.
The Evaluation about Vibratory Mixing Methods
Authors: Shen Hong , Duan Zhi Shan , Li Fei
Published: November 2012

With a wide range of applications of vibration technology in mechanical engineering, the vibratory mixing has been a hot topic and one of concrete mixing mechanical’s development directions. The author, in this text, introduces the methods of the vibratory mixing, and gives the comparison and evaluation of the existent vibratory mixing methods.
Prediction of Top Coal Caving Ability Based on Support Vector Machine
Authors: Shi Yong Kui , Sun Ting Ting , Hao Jian , Hao Shuai
Published: November 2012

This paper selected the factors as the coal mining depth, coal seam thickness, the dips, partings, main roof of the top coal caving as indicators, used the categorical data of the steep seam from domestic mining area as training samples for training. Based on one to one classification of SVM, the top coal caving ability prediction model was established. The example results show that the model prediction method is feasible, the prediction results have very high accuracy and reliability, and has certain promotional value.
Effect of Structure Parameters on Dynamic Characteristics of Piezoelectric Vibrator in Ultrasonic EDM Processing
Authors: Wang Hong Bing , Li Zhi Rong , Sun Chun Hua , Xu Hai
Published: November 2012

A piezoelectric vibrator in ultrasonic EDM processing is designed and fabricated. The structure parameters of the vibrator have a very significant impact on the dynamic characteristics. The effect of different structural parameters on dynamic characteristics of the vibrator is analyzed by using Finite Element Method(FEM), and the modal frequency and vibration amplitude sensitivities of the vibrator to the structural parameters are investigated by modal and harmonic analysis.. According the results of the sensitivities analysis, the structural parameters which have an important impact on the working modal frequency and the vibration amplitude are achieved. The vibrator is designed and made based on the above theoretical analysis. The dynamic characteristics of the piezoelectric vibrator are tested. In the case of exciting voltage of 100V (peak-peak value), the first-order longitudinal vibration frequency (working frequency) of the vibrator is 27.36 kHz, vibration amplitude is about9.8μm, which is in compliance with the theoretically analytical results.
Fault Diagnosis for AP1000 Plant Feed Water System Based on the Fault Petri Net
Authors: Liu Wei , Hu Rong Yuan , Yang Xi Yun , Dong Mu Jie
Published: November 2012

Abstract. The feed water system is one of the most important system for nuclear power plant. Based on an analysis for the working principles of the AP1000 plant main feed water system, a novel fault Petri net model and fault diagnosis method are proposed. The main feed water flow low alarm is a serious fault for the feed water system, Petri net theory is adopted to establish the fault model for this fault signal. Through the consequence and account for this model, fault reasons and reasons probability for the main feed water flow low have been obtained. Application shows that, the fault Petri net has more advantages than the fault tree in qualitative analysis and quantitative calculation. And this method is a new route for the nuclear plant systems’ fault diagnosis.
The Analysis on Controllability of Angular Ball Bearings with Considering the Installation Errors
Authors: Wan Shu Min , Li Jing Huai , Wu Xi Zhi , Lin Bin
Published: November 2012

A new definition was proposed-bearing control; in the case the bearing subjects to both radial and axial force only, the deformation is roughly symmetry about the Y-axis. When axial preload is 0.4 times greater than radial force, the bearing is controllable. In the case the bearing is exposed to pure torque and axial load, and axial preload is 50 times of the torque, the bearing is controllable. When complex load is applied on the bearing and axial preload is more than 0.418Fr+0.46Fa, the bearing is controllable. The application of spring equivalent bearing to simplify the model; the analysis of the impact on bearing exerted by a variety of installation errors and determination of the best installation form; the relation between installation errors and bearing load, and the relation between axial preload and the best installation form under the condition that the bearing is controllable, all of those are mentioned.
Application of Copula in Reliability Theory
Authors: Liu Zhe , Tao Feng He , Jia Chang Zhi
Published: November 2012

This paper discusses the changes of system lifetime and reliability functions in terms of the properties of Copulas when components are dependent, and provides a way in which you can judge the changes of systems with the definition of order according to the Copula of components.
Influence of Stiffener Structural Parameters on Compress Buckling Performance of Alloy Aluminum Stiffened Panel
Authors: Shao Qing , He Yu Ting , Kang Qing Shan , Zhang Teng
Published: November 2012

Finite element method (FEM) is applied to analyze the buckling performance of alloy aluminum stiffened panel subjected to uniform axial compression. With the skin thickness and stiffener pitch unchanged, the influence of flange thickness, flange length, stiffener thickness and stiffener height on compress buckling critical loads are studied by FEM. Important parameters influencing the buckling performance are identified and the results offer a referenced measure for the optimization design and engineering application of the structure.
Age-Hardening Characteristics of Cu-Ni-Si Alloy after Cold Deformation
Authors: Xiao Xiang Peng , Xiong Bai Qing , Wang Qiang Song , Xie Guo Liang , Peng Lijun
Published: November 2012

The microstructural features and heat treatment response of Cu-2.1Ni-0.5Si-0.2Zr-0.05Cr (wt.%) alloy have been investigated. The alloy was aged at 400°C、450°C and 500°C after a cold deformation of 70% reduction. The variation in hardness and electrical conductivity of the alloy was measured as a function of aging time. The results indicated the highest peak hardness value of approximately 205HV for the alloy aged at 400°C for 4h after the solution treatment and cold deformation. The alloy has two main phases, one is Ni2Si phase, and the other is Cr2Zr phase. The strengthening mechanisms of the alloy include spinodal decomposition strengthening, ordering strengthening and precipitation strengthening.
Aluminium Titanate-Aluminia Composites Synthesized by Heterogeneous Precipitation Method
Authors: Feng Chun Xia , Chen Jing Hua , Guo Wei , Jiao Bao Xiang , Lu Hong Bin
Published: November 2012

Aluminium titanate-alumina (AT-A) composites were sintered from the precursor powders prepared by two different methods: a simple sol-gel based heterogeneous precipitation method and a traditional blending method. The crystalline phase, microstructure, mechanical strength, sintering properties, and thermal expansion coefficient (TEC) of the sintered AT-A composites were investigated and compared. The heterogeneous precipitation method increases the homogeneity of the precursor powders and improves the mechanical and sintering properties of the AT-A composites. The AT-A composites with a Al:Ti ratio of 2.2 achieve the optimal performance where the bending strength is high and the TEC remains low.
Study on Tribological Performances of Friction Plate on MW Wind Power
Authors: Li Xiao Guang , Zhao Ping
Published: November 2012

The effects of contact pressure and sliding velocity and different environment conditions on the frictional coefficient of friction plate on MW wind power were studied by fatigue testing machine. The results show that the coefficient of static friction and difference between static and dynamic reduced with the increase of sliding speed, and reduced first and then increased and then reduced with the increase of contact pressure, and the change of dynamic friction coefficient was relatively flat with velocity and pressure under dry friction. The impact of water on the triological performance was the large, followed by oil when considering environment factors. Water and pressure and oil were the main influencing factors in considering all factors comprehensively.
Tensile Creep Behavior of Two NiAl-Based Alloys
Authors: Qi Yi Hui , Guo Jian Ting
Published: November 2012

The tensile creep behaviors of two NiAl-based alloys (HIPed NiAl-33.5Cr-0.5Zr and DS NiAl-28Cr-5.8Mo-0.2Hf) have been investigated. The creep results indicated that the creep curves of both alloys have similar shapes, which are composed of primary creep stage, steady-state creep stage, longer accelerated creep stage, and about 25-45% creep strain. The apparent stress exponents are in the range of 4.8-7.5 and the apparent activation energies of 520-584 kJ/mol were also analyzed. The creep deformations were controlled by the sub-grain boundary formation for the HIPed NiAl-Cr(Zr) and dislocation climb for the DS NiAl-Cr(Mo,Hf). The creep rupture data of both alloys obey the Monkman-Grant relationship.
The Melting Temperature of CaO-(2CaO•SiO2)-B2O3-SiO2-(Al2O3) Slag System
Authors: Wang Hong Ming , Li Pei Si , Li Gui Rong , Zhang Mian , Zhao Zhao , Zhao Yu Tao
Published: November 2012

The melting temperatures of CaO-(2CaO•SiO2)-B2O3-SiO2-(Al2O3) slag system were investigated. The results indicate that B2O3 has significant fluxing effect on this slag system. When the content of B2O3 is about 10% in these slag system, the mass ratios of w(CaO)/w(SiO2) and (CaO)/w(Al2O3) can be controlled in the scope of 1.5-8.0, the melting temperature of slag is still lower than 1340°C, which is suitable for steelmaking and secondary refining process. As a conclusion, when 10% B2O3 is employed as fluxing agent, a kind of CaO-based slag system with ultra-high basicity, ultra-low alumina content as well as low melting temperature can be obtained.
Block Shear Strength of Single Shear Four-Bolted Connections with Aluminum Alloys – Experiment and Design Strength Comparison
Authors: Kim Tae Soo
Published: November 2012

Experiments have been carried out to investigate the ultimate behaviors of single shear bolted connections assembled with four bolts (2 rows×2 columns bolt arrangement) under shear and aluminum alloy plate. End distance parallel to the direction of applied load is considered as main variables. All specimens failed in block shear fracture and curling (out of plane deformation) in the direction parallel to plate thickness was also observed for some bolted connections with a long end distance. The curling led to sudden ultimate strength reduction and test strength was compared with the block shear strength predicted by current design specifications.
Study on the Lining Erosion of Deep Reduction Electric Arc Furnace in Smelting Metallized Pellets Process Produced by Vanadium Titanium Magnetite
Authors: Qi Jian Ling
Published: November 2012

The erosion of the lining refractory of the deep reduction electric arc furnace is introduced, and the erosion appears in the process of smelting metallized pelltes produced by vanadium titanium magnetite. It shows that arc erosion, chemical erosion of oxides in slag, slag basicity, as well as joint and crack of brick are the main reasons of the serious erosion of the refractory through the analysis.
Study on Residual Stress in High-Speed Cutting NAK80 Mold-Steel
Authors: Pan Jian Xin , Zhou Zhi Xiong
Published: November 2012

An orthogonal cutting model was presented，and the cutting process was simulated by a finite element software based on the thermal-elastic-plastic FEM theory and updated Lagrange method.We obtained the distributions of residual stresses in machined layer of NAK80 mold-steel.The effects of cutting speeds，cutting depths and tool geometry on residual stress distributions were investigated. Comparing to experimental results，the conclusions are more accurate.
Effects of Sintering Conditions on Properties of a Warm Compacted Stainless Steel Powder
Authors: Ke Mei Yuan
Published: November 2012

Effects of Sintering atmosphere and temperature on properties of warm compacted 410L stainless steel powder were studied. Sintered density, hardness, tensile strength and elongation were measured. Results showed that in order to achieve high comprehensive properties, the optimal sintering temperature was 1230°C for 410L stainless steel powder. At the same sintering temperature, density and hardness sintered in vacuum were much higher than that sintered in cracked ammonia while tensile strength sintered in cracked ammonia were much higher than that in vacuum. When sintered in vacuum at 1230°C, sintered density was 7.45 g•cm-3, hardness was 65 HRB, tensile strength was 410 MPa and elongation was 29.5%. When sintered in cracked ammonia atmosphere at 1230°C, sintered density was 7.26 g•cm-3, hardness was 97 HRB, tensile strength was 515 MPa and elongation was 3.8%.
Research on Magnetorheological Elastomers Air Spring Based NR/SBR Rubber
Authors: Li Yan Ze , Ding Zhi Hua
Published: November 2012

Magnetorheological elastomers air spring, a practical new paten t is introduced, which is composed of magnetorheological elastomers, up-board, down-board and control system. The control system adjusts air pressure and real time stiffness. The air spring can enhance car capability of shock absorption, riding ride and steering stabilization, which can be applied to car’s suspension system.
The Characterization and Synthesis of Polyaniline Doped by Peroxo–Polytungstic Acid
Authors: Li Er Yuan , Wang Xiu Feng , Wang Xue Zhi
Published: November 2012

Polyaniline nanorods, nanoplates and urchin-like structures have been synthesized successfully by the template-free method of aniline and peroxo–polytungstic acid using ammonium persulphate as the oxidant in aqueous solution. The peroxo–polytungstic acid concentration and reaction temperature play important role in the formation process of polyaniline nanostructures. As the precursor concentration increased to 0.29mol/L, nanorods and urchin structures were obtained. With the decrease of temperature, the amount of PANI nanoplates with radially aligned dendritic surface structures will increase. The radially aligned dendritic surface is probably due to the molecular structures of the dopant, the linear nature of PANI chains and the second nucleation formation.
Synthesis and Characterization of Polyaniline Copolymer
Authors: Li Ting Xi , Zhao Yu Hua , Li Qian , Yuan Cheng Qian , Chen Quan Liang , Wei Meng , Gao Su Su , Sui Peng , Kong Na
Published: November 2012

Abstract. Polyaniline (PANI) and p-phenylenediamine (p-PDA)-aniline copolymer were prepared via a same microemulsion method. The structures of the PANI and p-PDA-aniline copolymer were characterized by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis（TGA）. The results revealed the difference of synthesis and characterization between PANI and p-PDA-aniline copolymer. It was shown that structure of the copolymer is almost similar to that of PANI, but the p-PDA-aniline copolymer has a better crystallization than PANI, and the thermal stability of the copolymer is higher than that of pure PANI.