bluuebunny/crossref_metadata_2025 huggingface dataset:
Error Analysis of the Plane Docking Mechanism
Authors: Xie Zhi Jiang , Huang Qiong Yu , Wang Cheng
Published: October 2013

The plane docking mechanism is the core part of the 6-DOF hybrid assembly and calibration platform, while the 6-DOF hybrid assembly and calibration platform has a core position in the entire assembly and calibration system device. The plane docking mechanism position and orientation docking accuracy directly affects accuracy of the entire docking process. For the purpose of efficiency, precision and security of the modules on end platform, error model was built. Meanwhile, the simulation verification and error compensation were done for the output platform. Ultimately, the smooth running of the entire laser device was ensured.
Research of Multiple UAVs Task Allocation Based on Improved Contract Net
Authors: Li Ya Wei , Li Bao An
Published: October 2013

This paper makes a research on multiple UAVs task allocation in cooperative combat. The control target is presented and the model is built of the problem. By introducing load factor, the traditional task allocation algorithm based on contract net is improved. With considering the mission capability of UAVs, a task allocation algorithm based on improved contract net is given. The improved algorithm can significantly reduce the communication between UAVs, and can optimize the task allocation process. The simulation results show that compared with the traditional task allocation algorithm based on contract net, the improved algorithm can improve the efficiency of UAVs task allocation and balance the task load between the UAVs, it can solve the problem of multiple types of tasks allocation effectively.
Line Selection Device Based on Double Tree Complex Wavelet
Authors: Sun Xia , Zhou Li
Published: October 2013

Single phase ground fault has the highest rate to happen in distribution network, use the method based on transient component can improve line selection accuracy effectively. sensitivity and directional selectivity can improved by using dual tree complex wavelet transform than using discrete wavelet translation, there is a decaying current fault line and normal line of difference, the difference is phase to phase delay reflected in current after wavelet transformation , the fault line and normal line zero sequence current and zero sequence current proportion relationship, there still worse a decaying direct current component, the normal phase between the two zero sequence currents are equal, therefore according to the phase relation after wavelet decomposition when will still be able to distinguish the fault line and normal line. Using the fast operation speed of digital signal processor can realized the fault line selection algorithm.
Study and Design on a Three Phase Power Source Based on FPGA Device
Authors: Xiao Li
Published: October 2013

In order to optimize design parameters of Power Source, an approach to selecting MOSFET and Filter and isolation techniques to improve system interference immunity is proposed. The parameter selections of MOSFET, capacitance and inductance have a certain impact on the property, volume and the cost of the system. The design of a three phase power source based on FPGA device is set as an example, its focus on the theory analysis, calculation and design of MOSFET, filter and the circuit of drive isolation and the analysis of selecting SPWM carrier frequency and power conversion efficiency. Finally, the experimental results and waveforms are presented.
The NC Grinding Machine Rebuilding for TG30 NC Lathe
Authors: Hou Pei Hong
Published: October 2013

Based on the characters of NC lathe and NC grinding machine, the NC grinding machine rebuilding for TG30 NC lathe is studied in this paper. According to the geometric parameters of grinding, choose appropriate TG30 NC lathe, keep the driving system of spindle and the feeding function of two axle linkage of NC lathe, increase the high speed rotating grinding head electric spindle, to realize the one-time processing of inner hole and groove fillet R grinding.
Research on Self-Propelled Artillery Digital AC Servo System Based on TMS320F2812
Authors: Huang Li Juan , Cheng Zhi Xin , Zhao Hai Yan , Wen Gu Sheng
Published: October 2013

The purpose of the present work is to present a overall design of digital AC servo system, which is based on PMSM on the background of Self-propelled Artillery servo system. A magnetic field Orienting control tactic based on vector control technology is explored. DSP CMOS chip TMS320F2812 is adopted as a control core to design total-digital AC servo system. Since the work current of the servo system is high, the MOSFET component is used to construct the power inverter circuit, rendering the high current controllable. The simulation results prove that the system has good dynamic performance.
IETM Technology is the Development Direction of Engineering Machinery Maintenance
Authors: Zhang Jun , Yan Zhao Hong , Qiang Zhang Jian
Published: October 2013

Based on the interactive electronic technical manual (IETM) characteristics of the analysis, combined with the current situation of China's engineering machinery repair, comparative analysis of technical advantages of using IETM technology in engineering machinery repair in data acquisition technology, from the speed, fault isolation efficiency and personnel's work efficiency and other aspects, discusses the necessity of its application; combined with IETM production standards, from the main creative part of IETM, such as information generation, information management, production of interactive interface, several aspects of publishing, explains IETM make the development process and the main production platform. By using the structure block diagram, showing the method of information production and information management mode, and the main modules in the block diagram and function are described; and discusses future development proposals.
Study of Maintenance Mission Requirement Analysis Method Based on FMEA
Authors: Lian Guang Yao , Yan Peng Cheng , Huang Kao Li , Cai Li Ying
Published: October 2013

The requirement analysis of maintenance mission is the main content of the statement work of the system of equipment maintenance and guarantee, which is also the foundation of the construction of the system of maintenance and guarantee. Combining with the current work experience of the statement of the system of equipment maintenance and guarantee in researching, this essay discusses requirement analysis method of maintenance mission from theory basement, working system and procedure, and uses it in the process of the statement work. The effect is obvious.
Bioleaching of Phosphorus from Hematite with Mixed Bacteria
Authors: Huang Teng , Gong Wen Qi , Bao Guang Ming , Lei Shao Min
Published: October 2013

Sphingomonas sp. is an abundant and novel microbial resource,as for the little awareness of Sphingomonas sp., its ecological and economical values are not well understood. This paper focuses on the bioleaching of phosphorus from hematite with mixed bacteria. When compared with Acidithiobacillusferrooxidans (At.f), Sphingomonas sp. can increase the leaching rate by 1.5 times,and can also solve the problem of generating higher sulphur content by At.f. Thus Sphingomonas sp. will have an extensive application prospect in biohydrometallurgy.
Technical Properties of Some Plant Fibres Compared with Glass Fibre
Authors: Sumaila M. , Ibhadode A.O. Akii
Published: October 2013

The tensile strength, specific tensile strength, breaking force, tenacity and percent elongation of some fibres extracted from eight fibrous plants found in Northern Nigeria were determined with a view to ascertaining their suitability for the replacement of glass fibre in plastic composites. Also the crimp properties and work of rupture with the specific work of rupture for all the plant fibres were analysed. The fibrous plants were Sisal (Agave Sisalana) (ASA), Lalloh (Corchorus Triden L.) (CCR), Dargaza (Grewia Mollis Juss) (GRW), Kenaf (Hibiscus Cannabinus L.) (HCB), Goruba (Hyphaene Thebaica)(HYP), Sukuwa (Sida Acuta) (SDA), Karlgo (Piliostigma Thoningii) (PTA) and Shikuri Tuggah (Urena Lobata) (ULB). Their properties were compared with E-Glass. The results show that whereas the highest tensile strength of the plant fibre (ASB) was about one-third that of the glass fibre, the highest specific tensile strength of the plant fibre (HCB) was about 5 times that of the glass fibre. The percent elongation of the plant fibres except HYB and SDA were at least 5.6 times that of the glass fibre. The specific work of rupture for the plant fibre were also found to be upto 31% higher compared with that of glass. Three of the plant fibres, (HCB, ASA and ULB) were observed to be possible replacements for the classic glass fibre.
Electrokinetic Potential for Characterization of Nanosctructured Solid Flat Surfaces
Authors: Kolská Zdeňka , Kasálková Nikola Slepičková , Siegel Jakub , Švorčík Václav
Published: October 2013

Electrokinetic potential (zeta potential) is a characteristic parameter for description of the surface chemistry of solid flat materials and it can be used for a fast analysis of materials modified by different chemical or physical methods. Due to its sensitivity, zeta potential is able to distinguish surface modified by coating with monolayers of various materials or nanostructures created after plasma treatment. Also metal nanostructures deposited on surfaces can be characterized by zeta potential. It can also be used for isoelectric point determination of materials. We present data on zeta potential in 0.001 mol/dm3 KCl at constant pH7.0 and also in pH range (2.5-7.0) for isoelectric point determination for pristine polymers PET, PTFE, PS, LDPE, HDPE, PLLA, PVF, PVDF, PMP and polyimides (Upilex R, Upilex S, Kapton). The zeta potential of selected polymers, modified by plasma and by chemical coatings (e.g. by biphenyldithiol or polyethyleneglycol) or by gold deposition was measured too. Zeta potentials of these modified materials were also studied to confirmation that electrokinetic analysis is acceptable method for their fast description.
Growth, Structure and Optical Properties of CuNi-Oxide Films for Nanophotonics and Photovoltaics
Authors: Pappas S.D. , Grammatikopoulos S. , Poulopoulos Panagiotis , Trachylis D. , Velgakis M.J. , Meletis Efstathios I. , Schommers W. , Politis C.
Published: October 2013

Cu and Ni from CuNi metallic targets (composition 20-80 and 46-54 at.%) are deposited on Corning glass, quartz and the native oxide of Si (100) wafers by direct current magnetron sputtering in a high vacuum chamber (base pressure 5 x 10-5 mbar). The CuNi films, with thickness 40 200 nm, are post annealed at temperatures 400 - 500 °C in a furnace under atmospheric air in order to be fully oxidized. The structure of the films is studied by x-ray diffraction experiments. Phase separation of the oxides is evident. The optical properties are studied via ultraviolet-visible light absorption spectroscopy. The spectra of CuNi-oxide films are compared with the spectra of the pure CuO and NiO films. Features originating from both CuO and NiO are detected in the spectra of the CuNi-oxide thin films.
Influence of Work-Hardening on Wear Resistance of Machined Surface of Aviation Aluminum Alloy
Authors: Fu Xiu Li , An Zeng Hui , Qiao Yang , Men Xiu Hua
Published: October 2013

Work-hardening of machined surface plays an important role in the evaluation of surface quality and performance of wear resistance in the process of machining components. In this study work-hardening of machined surface during milling 7050-T7451 aluminum alloy is investigated using micro-hardness experiments under different cutting conditions. Moreover, the wear resistance of machined surface including wear quantity and friction coefficient are obtained and studied by means of high speed ring-block friction-wear tester. The work-hardening and wear resistance are particularly sensitive to cutting speed. Friction coefficient has marked drop trends and the tendency of wear quantity is ascend in first and descend at last as work-hardening increases. The comparison of wear resistance under different cutting conditions shows that the wear resistance of machined surface can be directly affected by work-hardening and machined surface obtained by high speed milling with higher micro-hardness have more superior in wear resistance performance.
Study on the Prediction of Drilling Forces on Cortical Bone Based on Finite Element Simulation
Authors: Hu Ya Hui , Zhang Qing Yun , Yue Xiao Yu
Published: October 2013

The changes of drilling forces during bone drilling provide a useful index for evaluating the risk of potential damage to the bone. The aim of the work is that an elastic-plastic dynamic finite element model is used to simulate the process of a drill bit drilling through the bone. The finite element model was set up in the Abaqus6.11; the prediction model of the drilling force was gotten by using the regression orthogonal experiment and data processing software Matlab7.0. Diverse values of drilling speed, feed rate and drill diameter are important factors which will lead to changes in the drilling forces. By controlling the drilling parameters can obtain the optimal drilling force. The results show that the diameter has the greatest influence on the drilling force, the drilling speed the second, the feed rate the last.
Analysis of Temperatures in Sawing of Granite Based on Parabolic Heat Distribution
Authors: Zhang Yu Xiang , Fang Cong Fu , Huang Guo Qin , Yu Yi Qing , Xu Xi Peng
Published: October 2013

A temperature model was advanced based on a parabolic heat flux distribution in sawing contact zone in the present paper. It is found that the maximum temperature for parabolic distribution is more higher than that for triangular distribution in the sawing contact zone, and the location point of the maximum temperature for parabolic distribution in the sawing contact zone is much nearer the entrance than that for triangular distribution.
Study on Thermal Elongation Error of Whirlwind Hard Milling Ballscrew
Authors: Li Yan Feng , Song Xian Chun , Jiang Hong Kui , Xu Xiang Rong
Published: October 2013

Whirlwind hard milling is a new high-efficient and environmental technology for maching process ballscrew thread. Thermal elongation of the workpiece in processing is one of the main reasons causing the screw-pitch error. The screw-pitch error due to thermal elongation caused by milling heat were analyzed . The dynamic temperature distribution simulation and thermal elogation of the workpiece were carried out with ANSYS software.Compared the simulation results with measured temperature during processing of the workpiece,the temperature distribution pattern is consistent.The result indicate that the law of thermal elongation of the free end and unprocessed section of ballscrew simulated by ANSYS is helpful to compensate screw-pitch error caused by thermal elogation.
Temperature Field and Thermal Residual Stress of Grinding GH4169 with Conventional Aluminum Oxide Wheel
Authors: Wang Tao , Chen Guo Ding
Published: October 2013

The constitutive relationship of GH4169 superalloy was investigated. The grinding thermal load acting on GH4169 workpiece in grinding process with conventional aluminum oxide wheel was determined by using the method combining finite element method (FEM) with experiment. The grinding temperature field and grinding thermal residual stress generated in GH4169 were calculated via finite element method (FEM). Finally, the relation between grinding parameters and grinding temperature field and that between grinding parameters and thermal residual stress were discussed.
Investigations of Surface Roughness with Cutting Speed and Cooling in the Wear Process during Turing GH4133 with PCBN Tool
Authors: Ji Wei , Liu Xian Li , Yan Fu Gang , Xiao Sheng Lei , Fan Meng Chao
Published: October 2013

The high temperature strength of Ni-based superalloys coupled with excellent corrosion resistance make them ideal for aerospace applications. However, the difficulty in finish machining superalloys with the carbide tools presents the short tool-life. Polycrystalline Cubic Boron Nitride (PCBN) is potential to machine superalloys. To data, there are many researches about PCBN tool wear, but only little papers showing how the surface roughness and the wear speed are influenced by cutting parameter and the coolant during the differences periods of PCBN tool wear. This investigation has been conducted to show that the PCBN tool wear is slower with cooling that without cooling during cutting superalloys with PCBN tool especially in VB up to a certain value. It is shown that tool fracture can be reduced by using the cooling. In the process of PCBN tool wear, in addition, there are some differences of the effect of the cooling for roughness Ra values.
Ultra-High-Speed Grinding — Theoretical Basis and Development of a Grinding Machine Tool
Authors: Yang Lu , Fu Yu Can , Xu Jiu Hua , Tian Lin , Zhao Jia Yan
Published: October 2013

This study describes the theoretical basis of ultra-high-speed grinding. In addition, a new grinding machine tool whose maximum grinding speed can reach 450m/s has been recently developed, particularly, some of main components are basically discussed. Finally, this paper concludes with a presentation of current work and some future desirable plans in the area of ultra-high-speed grinding by means of the developed grinding machine tool.
Study on Wear Mechanism of Carbide Tool in Machining Inconel 718
Authors: Fan Yi Hang , Zhou Liang , Song Shuang Zhu , Sun Feng Lian
Published: October 2013

Tool wear is a problem in machining nickel-based superalloy Inconel 718, and it is thus of great importance to understand and quantitatively predict tool wear. The experiments of machining Inconel 718 with cemented carbide tools (uncoated and coated) were carried out. Some new observations and analysis of tool wear through CCD, SEM and EDS were done. The results showed that at low cutting speed, the built up edge (BUE) formed easily and dropped at last which caused severe cutting tool breakage. When cutting speed came to 30m/min, the main reason that caused cutting tool wear was that the tool material fell off from the tool body at the form of wear debris. What’s more, the element diffusion between tool and workpiece and oxidation reaction all accelerate the formation and the cast of the wear debris.
Study on Helical Groove and Circumferential Cutting Edge Machining Simulation of End Mill
Authors: Li Guo Chao , Sun Jie , Li Jian Feng , Xiong Qing Chun
Published: October 2013

A purely analytical method, based on the meshing theory, is presented to establish the exact helical groove and circumferential cutting edge model of end mills, for the solution of its low design precision and efficiency problems. Firstly, a coordinate system to represent the relative space position relations between grinding wheels and end mills is built and the mathematical model of the helical groove is precisely calculated with a given wheel profile and relative movements between the wheel and the workpiece. Then, the rake angle, inner radius and wheel positions of machining the clearance faces is computed. Finally, a 3D model of the end mill is generated by using OpenGL.
Establishment of the Low Defect Ceramic Cutting Tool Database
Authors: Zou Chang Bin , Huang Chuan Zhen , Zou Bin , Fei Yu Huan , Liu Han Lian , Zhu Hong Tao , Wang Jun
Published: October 2013

This paper analyzes the reasons of the defects generation of the ceramic cutting tool materials. The defects in the ceramic cutting tool materials are caused by chemical compatibility and physical mismatch during the designing process, and caused by grain abnormal growth and sintering parameters during the preparation stage. The database of low defect ceramic cutting tool is established and the data structure of the database is described. The users can use the database to design the tool material system through the mode that can reduce the defects.
Wear Behavior of Ti(N,C)-Al2O3 Coated Cemented Carbide Tools during Milling Ti2AlNb-Based Alloy
Authors: Ma Xiao Di , Xu Jiu Hua , Ding Wen Feng , Lv Dong Sheng , Fu Yu Can
Published: October 2013

Ti2AlNb-based alloy is regarded as lightweight high-temperature structural material, which is expected to replace the nickel-base super alloy due to its low density, high elastic modulus, strength retention at elevated temperature, outstanding oxide resistance. However, these excellent properties also make Ti2AlNb to be difficult-to-cut material. In this paper, the milling experiment of Ti2AlNb alloy was carried out using Ti(N,C)-Al2O3 coated cemented carbide tools. SEM and EDS analysis was utilized to observe the worn tools to determine the tool failure modes and wear mechanisms. Tool life when milling Ti2AlNb was short and heavily dependent on the cutting parameters. During milling, coating material of the tool was separated rapidly from the base material. When the cutting speed exceeded 100m/min, serious cracks appeared on the tool surface. Thermal fatigue, adhesive and attrition were the predominant wear mechanisms of the coated tools.
Tribo-Map of CVD Diamond Film Sliding against Silicon Nitride in Air
Authors: Chen Su Lin , Shen Bin , Sun Fang Hong
Published: October 2013

The tribo-map of typical CVD diamond film exhibiting the interaction between the wear rate, friction coefficient and friction conditions would help optimize the working parameters of CVD diamond film coated tools and wear-resistance components. The tribological behaviors of CVD diamond films sliding against Si3N4 balls were studied by conducting a group of tests on the ball-on-plate type reciprocating friction tester under several sliding speeds and normal loads in the ambient air. The examined MCD films and NCD films were deposited on square flat WC-Co substrates. The worn surfaces on the diamond films were observed by SEM and the wear volumes of diamond films were measured by surface profilometer. The results indicated that the influences of the sliding speeds and normal loads on the friction coefficients for both MCD films and NCD films were obvious. When the load was 6 N, MCD film obtained the lowest friction coefficient of 0.11 at the sliding velocity of 0.2 m/s, while for NCD film the minimum value was 0.07 as the sliding speed was 0.13 m/s. The wear rate of the MCD film decreased as the load improved, while for the NCD film, the tendency was just the opposite. The influence of sliding speed on the wear rate of the MCD films was not distinct, while for the NCD films, the sliding velocity greatly affects their wear rate. The wear rates of most NCD films were around 0.2×10-7 mm3/Nm, while those of the MCD films fluctuated from 0.6×10-7~1.6×10-7 mm3/Nm. To elucidate the effect of operating environment on wear mechanism of diamond/ Si3N4 tribo-pair, the tribo-map was developed.
Research on Geometric Modeling Method of Finishing Milling Cutter with Fir-Slot
Authors: Chen Hui Xian , Chu Gong , Wu Meng Pei , Yang Hui Jun
Published: October 2013

Because of the influence of tool geometry, when the fine slotting cutter is cutting, the cutting condition at every point of the type line cutting edge varies, which will lead to uneven loading on the whole cutting edge. Finally, partial earlier failure of the cutter would be initiated. To solve this problem, this paper presented a cutting simulation of the slotting cutter with zero rake angle, which could draw the variation law of cutting force at different locations on the type line. On the basis of micro-elemental milling force model, this paper established mathematical models of different sections along the turning axis of cutting tool, in which the relief angle changed to adapt to the variation of cutting force. The variation law of relief angle could be found by utilizing liner regression analysis. Then the 3D model of tool could be reconstructed. According to cutting experiment analysis of the reconstructed model, the distribution of cutting force at every point of the cutting edge tended to be reasonable, and the rationality of the optimal model was proved. This will offer a new idea to improve the level of slotting cutter design as well as a reference of complex forming cutter design that was completed by using the modern design method.
Development of Ultra-Precison Single-Plane Lapping Machine
Authors: Song Yue Xian , Li Qing Jian , Li Sheng Lan , Wang Cheng Yong , Zheng Li Juan
Published: October 2013

An ultra-precision lapping machine is developed, with precision turning technology to condition lapping plate in situ, pressurizating by cylinder pressure, and cooling frictional heat with inner cooling system, the lapping machine is used for ultra-precision lapping of brittle materials. The design concept and the structure of the key components of the utra-precision sngle-plane lpping mchine are discussed. After precision turning, the flatness of lapping plate is down to 0.002 mm/400 mm, and experimental results show that the flatness of circular grating glass has been greatly improved after ultra-precison lapping.
Rotary Ultrasonic Machining of Sapphire: Feasibility Study and Designed Experiments
Authors: Zhang Cheng Long , Feng Ping Fa , Pei Zhi Jian , Cong Wei Long
Published: October 2013

Sapphire, widely used in high-speed integrated-circuit chips, thin-film substrates, and various electronic components, is regarded as one of the most difficult to cut materials owing to its great hardness and low fracture toughness. Rotary ultrasonic machining (RUM) has been regarded as an effective processing method for hard and brittle materials. In this paper, RUM process is introduced into the drilling of sapphire for the first time. The feasibility to machine sapphire using RUM is studied. Moreover, results of a designed experimental study into RUM of sapphire are presented to discuss the main effects as well as interaction effects of process parameters (ultrasonic power, spindle speed, and feedrate) on outputs. The process outputs investigated include cutting force and edge chipping size.
Fabrication of Wave-Like Microstructure on the Bottom of Microflow Channel of Metallic Bipolar Plate
Authors: Tang Hong Liang , Wan Zhen Ping , Tang Yong
Published: October 2013

Metallic bipolar plates with unique wave-like microstructure on the bottom of microflow channel have shown promising prospects for the application in proton exchange membrane microfuel cell. A novel method—milling with special thin slotting cutters is developed for fabrication of wave-like microstructure on the bottom of microflow channels. The special thin slotting cutter is manufactured by removing one or several teeth every one tooth of the traditional slotting cutter regularly. Forming mechanism of wave-like microstructure is presented and experimental tests have been conducted for validation of the feasibility of the novel method. Results show that the wave-like microstructure can be successfully fabricated on the bottom of microflow channel. The bottom of bipolar plates with wave-like microstructure is not a flat plane, but a wavy groove. The wavelength and amplitude of wave-like microstructure increase with the increase of feed speed and the number of removed teeth.
Analysis on Regularity of Fatigue Crack of Heavy Carbide Insert Under Dynamic Alternating Loading
Authors: Liu Li , Cheng Yao Nan , Qian Jun , Gong Ya Nan , Wu Ming Yang , Yan Fu Gang
Published: October 2013

In the machining process of large parts, the dynamic alternating loading suffered by heavy carbide insert is very large, so the fatigue failure of the insert is serious. Through the analysis the effect of dynamic alternating force - thermal load on insert’s crack, and the fatigue crack experiment of inserts under dynamic alternating loading will be done, the formation conditions and distribution law of fatigue cracks can be researched under the effect of dynamic mechanical shock and thermal shock. And the fatigue crack will be theoretical analysis through the fatigue curve in the range of test cutting parameters. It can provide effective basis for the optimizing the heavy-duty cutting parameters and reducing the fatigue crack failure of heavy-duty cutting insert.
Effects of TiN Content on Mechanical Properties and Microstructure of ATN Materials
Authors: Wang Min , Zhao Jun
Published: October 2013

In order to investigate the effects of TiN content on Al2O3/TiN ceramic material (ATN), the ATN ceramic materials were prepared of TiN content in 30%, 40%, 50%, 60% in the condition of hot press sintering. The sintering temperature is 1700°C, the sintering press is 32MPa, and the holding time are 5min, 10min, 15min. The effects of TiN content on mechanical properties and microstructure of ATN ceramic materials were investigated by analyzing the bending strength, hardness, fracture toughness. The results show that ATN50 has the best mechanical property, its bending strength is 659.41MPa, vickers hardness is 13.79GPa, fracture toughness is 7.06MPa·m1/2. It is indicated that the TiN content has important effect on microstructure and mechanical properties of ATN ceramic materials.
An Optimized Particle Filter for Signal De-Noising Processing
Authors: Chen Han Xin , Tu Ling , Sun Kui , Liu Cen
Published: October 2013

The traditional particle filter (PF) algorithm is well known for signal noise reduction processing, but it exists problems of particle impoverishment and cumulation of estimation errors. An optimized PF algorithm called RBF-PF is proposed in this paper, which uses radial basis function network for training and optimizing the process of particle filter in the sampling. Experimental analysis verifies that the new method used to gain the signal-to-noise ratio is better than traditional PF algorithm during dealing with the added noise signal.
Analysis of the Factors Affecting Stability of Hard Cutting System
Authors: Chen Guang Jun , Kong Ling Guo , Xu Rui , Liu Xian Li
Published: October 2013

The flutter in the hard cutting has a significant impact on the efficiency of production, the quality processed, the environment in processing, the cost, and the life of the machines and tools . However, the application of the method named numerical simulation in MatLab predicted the stability limitation of the hard cutting system, analyzed the influence of cutting system dynamics parameters on the stability limitation of system, at the same time, an experimental verification of hard cutting had been carried out. And the results of analysis showed that improving the system stiffness K and cutting system damping ratio ζ, cutting the stiffness coefficient Kc and the direction coefficient , adjusting the cutting speed to the correct, reducing the amount of turning ap, decreasing the tip radius of circular arc , increasing the feeding f can be used as the methods of vibration reducing in the system. So the results of the research provide reference for the reasonable choice of cutting parameters.
Development and Research on the Dynamics Simulation System for Surface Grinding Process with Diamond Wheel
Authors: Chen Yong , Huang Guo Qin
Published: October 2013

Vibration during high-speed surface grinding process is one of important factors to influence surface precision of machined workpieces and lead to low efficiency of grinding machine. Process parameters are usually obtained from empirical data or reference manuals for the avoidance of serious vibration even chatter and its effect. As a result, it generally leads to low rated power of machine tool and long processing cycle. To solve the problem, designing and development on a dynamics simulation system for surface grinding with high accuracy ,which will be capable to predict a series of dynamic characteristics in time and frequency domains, such as grinding force-vibration, as well as phase/frequency characteristics, relative power spectral analysis etc is necessary and shows good application prospect. Meanwhile, the system will be used to indicate the process parameters optimization and investigate distribution characteristics of grain chip thickness and surface topography precision. In the paper, surface grinding process with diamond wheel is chosen as the study object and its dynamic characteristics are investigated. Based on studies on the comprehensive influence mechanism of regenerative chatter theory and wheel run-out rotational model on instantaneous grinding chip thickness of grain unit, analytical models of grinding force are improved. Differential equations of damper grinding vibration system with two-degree-of-freedom and a close-loop control system model with regenerative chatter feedback circle on the basis of interaction behaviors of force and vibration are built. Several relevant numerical methods are introduced to develop the simulation system of grinding dynamics. By comparative analysis on solution accuracy, steadiness and convergence of the correlative algorithms, explicit Runge-Kutta formula is identified as the best solution to simulation system modeling. On the basis of the above work, main subsystems and functional modules in the system are presented. The whole designs of framework and prototype systems are finished.
Analysis and Test of the Driving Wheel of Planetary Rover in Simulated Lunar Surface
Authors: Huang Yu Xin , Wang Tong Yu , Lin Lin , Wang Li Meng , Zhang Hu
Published: October 2013

In this paper, a rigid wheel of the rover is designed. We discuss the physical parameters of the typical metal materials to analyze the static load stress of the structure of rigid wheel. Comparing the moon environment with the earth environment, we draw up various optimization schemes and deduce the model of subsidence relationship of the wheel and the soil. In addition, the tephra is used to make the simulated lunar soil applied in the basic mechanical experiments of the vehicles in the moon. Then we use the optimized rigid wheel to conduct the test experiment of different vertical load and slip ratio of rolling on the simulated lunar soil. The subsidence relationship model of the wheel is discussed and we have analyzed the experimental data.
A New Method of Point-to-Point Comparison Interpolation for Involute
Authors: Yan Kai Yin , Wang Jing Ping , Zhou Ru Zhong
Published: October 2013

This paper presents a new interpolation method for involute in polar coordinate system based on pulse incremental algorithm and point to point comparison method. The new idea is that the diameter deviation of the base circle at any interpolation point is calculated and introduced to be a criterion to determine the feeding direction of next step. Consequently, the interpolation computing becomes very simple and high contour accuracy can be obtained. With slight modification of numerical control (NC) system, this method can be realized on NC milling machines equipped with two simultaneous movement axes. A case study has shown that this method is feasible and effective.
Design of Automatic Control System of Grinding Zone Temperature in Grinding Hardening
Authors: Cheng Wei , Liang Ping
Published: October 2013

The grinding hardening is a new technology which utilized thermal of grinding zone to heat-treat the workpiece surface layer. In grinding hardening process, grinding zone temperature directly affects the quality of surface layer of heat treatment. The high temperature heat pipe is very good device of control heat transfer. In order to make the grinding zone temperature slightly change in grinding process, this paper describes a design of temperature automatic control technology. A high temperature heat pipe contact with the workpiece’s grinding zone. The zone temperature is measured using infrared radiation pyrometer and the temperature data will be used to control the high temperature heat pipe’s thermal resistance through the PID controller. That is that the PID controller will adjust the contact area between workpiece and high temperature heat pipe, thus achieves control of workpiece’s surface hardening requirements.
Comprehensive Cutting Force Model for Milling Processes with Solid End Mills and Inserted Cutters
Authors: Song Qing Hua , Liu Zhan Qiang , Ai Xing
Published: October 2013

A generalized cutting mechanics model is proposed for milling processes with solid end mills and inserted cutters. The unified mathematical model is employed for the description of the solid milling flute and insert on a reference tool body. The friction and normal forces acting on the rake face are transformed into milling coordinates using a general transformation matrix by simply assigning operation specific parameters. The generalized model can be used to predict and optimize the machining operations including solid end mills and inserted cutters.
Advanced Nano-Finishing Process of SrTiO3 Substrate by Cluster MR-Effect Plate
Authors: Bai Zhen Wei , Yan Qiu Sheng , Lu Jia Bin
Published: October 2013

As a new multifunctional material, strontium titanate (SrTiO3) ceramic has a wide application in grain boundary layer capacitor (GBLC) with the microstructure characteristics of semi-conductive crystalline grain and insulated boundary. An ultra-precision nanofishing technique is developed to lap and polish the brittle and thin SrTiO3 substrate with the cluster MR-effect plate where the abrasives are constrained by the cluster MR-effect chains, under the influence of a magnetic field, the carbonyl iron particles (CIPs) and non-magnetic abrasive particles remove material from the surface of workpiece being machined in this paper. Mahr XT20 roughmeter, Keyence VHX-600 and Olympus S4000 microscopes are used to investigate the characteristic of machined surface and the mechanism of material removal. An ultra-smooth planarization surface of SrTiO3 substrate with surface roughness Ra 3.8 nm (Mahr), RMS 0.973 nm (Veeco interferometer) is obtained under a high efficiency. It is found that the pore structures of the sintered substrate would weak the machinability of SrTiO3 and influence the further improvement of surface quality.
Experimental Study in High Efficiency Milling of Hydrogenated Ti6Al4V Alloy
Authors: Yang Shu Bao , Xu Jiu Hua , Fu Yu Can , Zhu Guo Hui
Published: October 2013

Milling tests were undertaken to analyze and compare the machinability of hydrogenated titanium alloy Ti6Al4V. Uncoated WC-Co tool inserts were used in the study. The feed and the depth of milling were maintained constant, and only the milling speed was varied because it is the most affecting parameter. Results showed that cutting force and tool life were greatly influenced by the contents of hydrogen. Tool life decreased at first and then increased gradually with the increase of hydrogen content, and the maximum magnitude decrease of tool life is about 0.2%H, meanwhile, the maximum tool life is about 0.5%H. However, with the increase of cutting speed, the favorable effect of hydrogen on the titanium alloy machinability would be weakened even disappear, therefore, 50-100m/min would be a suitable choice of cutting speed.
Study on Acoustic Emission Characteristics of Fiber Reinforced Ceramic Matrix Composites
Authors: Yang Mei Ning , Song Xiao Fei , Lin Bin , Yang Yang , Peng Wen Zhen
Published: October 2013

Through acoustic emission on-line monitoring system, the effective value of acoustic emission is measured, which produces in the grinding of fiber reinforced ceramic matrix composites. The mapping relationship, grinding parameters and the effective value of acoustic emission, is discussed qualitatively. And the influence of different grinding directions on the effective value and spectrum also is studied. These could be significant guidance for controlling the grinding process to improve the machining quality.
Research on Critical Cut Depth of Glass BK7 in Diamond Cutting
Authors: Jia Peng
Published: October 2013

In diamond cutting of optical glasses, the magnitude of critical depth of cut for brittle-ductile transition is an important factor affecting the machinability of the work material in terms of production rate and surface quality. In this work, scratching tests with increasing depths of cut were conducted on glass BK7 to evaluate the influence of the cutting fluid properties on the critical depth of cut. Boric acid solutions of different concentrations were selected as cutting fluids in the tests. The resulting scratches were examined utilizing a white light interferometer and the values of the critical depth of cut were determined based on the observations of the micro-morphology of the scratch surfaces produced. Experimental results indicated that compared with the process without cutting fluid action, the critical depth of cut in diamond cutting of glass BK7 can be increased by using boric acid solution as the cutting fluid.
Optimization of the Two-DOF Passive Damper for the Machining Vibration Control Based on the SDM
Authors: Yang Yi Qing , Dai Wei
Published: October 2013

Two-DOF (Degree-of-Freedom) passive damper is found to be able to attain better performance than the Single-DOF damper in the machining vibration control. However, the optimization is much more complicated as there are more design variables. A new approach of optimizing the Two-DOF passive damper is proposed based on the Structural Dynamical Modification (SDM) method. The physical model of Two-DOF damper damping single mode is presented, and the Frequency Response Function (FRF) of the primary structure are formulated. Numerical simulation is carried out and the optimal geometrical parameters are obtained with an objective ofHnorm. It is found that the Two-DOF passive damper can achieve the best vibration suppression effect than the SDOF damper, two separate SDOF dampers and uniform-density bar while the mass ratio is the same.
Experimental Study on Wear and Fracture of Ball-End Milling Cutter in High Speed Machining Stainless Steel 0Cr13Ni4Mo
Authors: Chen Dong , Tan Guang Yu , Liu Guang Jun , Li Guang Hui
Published: October 2013

An experimental study on wear and fracture of ball-end milling cutter in high speed machining martensitic stainless steel 0Cr13Ni4Mo is studied in this work. Through the SEM micrographs and energy spectrum analysis of the wear pattern of the rake face, severe coating spalling is found near the main cutting edge. Fracture is seen on the entire cutting edge, in which micro-chipping occurs on the both ends of the cutting edge, and chipping occurs in the middle of the cutting edge and is the conchoidal spalling on the rake face. Combined with the high-speed photography of the milling process, the fracture area is consistent with the chip-adhesion area.
Extraction of Cutter-Workpiece Engagement for Multi-Axis Milling
Authors: Yang Yun , Wan Min , Zhang Wei Hong , Ma Ying Chao
Published: October 2013

Cutter-workpiece engagement (CWE) is the contact zone where the cutting flutes enter and exit the workpiece as a function of axial depth of cut. Determination of CWE is the basis for predictions of cutting forces, machining error and chatter stability in multi-axis milling. In this paper, a solid modeling approach is developed to extract CWE for multi-axis milling by means of removal volume, which is obtained by subtracting analytic tool swept volume from in-process workpiece. Meanwhile, the feasible contact surfaces are used to trim the removal volume in order to determine CWE surfaces. Simulations are also performed to confirm the validity of the proposed method.
A Study on Tribological Behavior of Engineering Ceramics - Representative Metals
Authors: Wang Peng Xiao , Tian Xin Li , Zhang Bao Guo , Wang Long
Published: October 2013

In order to obtain the optimal engineering ceramics-metals pair with the best tribological performance, the tribological orthogonal tests for engineering ceramics such as Si3N4, SiC, ZrO2 and representative metals such as 45steel, CCr15 bearing steel, tin bronze QSn4-3 and tin-based babbit ZChSnSb8-4 with oil-less lubrication were carried out by using UMT-3 wear machine and SEM. Single factor analysis of load on friction and wear properties of Si3N4- babbit pair was performed. The results indicate that ceramic-metal pairs possess excellent tribological performance. Si3N4- babbit pair has the lowest friction coefficient and SiC-babbit pair is best in attrition. The friction coefficient varies sharply on low loads and the wear rate monotonous rises with the increase of load.
Finite Element Analysis for Strength Checking of Driven Wheels of "Ferris Wheel" Amusement Machine
Authors: Li Bing Bing , Liu Chun Zhe , Wu Jing Ran
Published: October 2013

This paper illustrates finite element analysis software aided strength checking of driven wheels of Ferris Wheel amusement machine. After analyzing framework bearing under extreme working conditions, it comes to a reasonable conclusion that the experience shows that 3D design and analysis software can help improve the productivity of amusement machine research and development, and finite element software can be applied to make it more efficient to design and check parts under intricate force.
The Analysis on Dynamic Characteristics and the Structural Optimization of HRG Polishing Machine Tool
Authors: Chen Ming Jun , Yu Lin , Liu He Nan , Chen Wan Qun
Published: October 2013

The dynamic characteristics of machine tool directly affect machining accuracy of the final parts. Taking the self-developed HRG ultra-precision polishing CNC machine tool as the research object, the simplified finite element model is established with the finite element analysis software to do the dynamic analysis and the natural frequency is detected as the index of the dynamic performances. Based on the comparative analysis of the natural frequency and vibration modes, the gantry and the supporting frame are recognized as structural weaknesses of the machine tool, and then the modal test is done to verify simulation results. Eventually the structural weaknesses are optimized effectively. The 1st order nature frequency of the optimized gantry and the optimized supporting frame is increased 75.5% and 80.8% respectively so that they have better dynamic performances, resulting in offering higher workpiece quality and process stability.
Experimental Study on the Influence of Cutting Parameters on Thread Precision of External Thread Turning
Authors: Li Kang , Jiang Li , Chen Ming
Published: October 2013

External thread turning is a complex 3-D process in which the cutting conditions vary over the thread cutter profile. There are a lot of factors that affect the thread precision. This paper focuses on the influences of the lubrication method, cutting speed and the number of passes on the thread precision. Several stainless steel turning tests were conducted. The results showed that lubrication method was the most important factor that affected the thread precision, while the number of passes was the least important one. MQL (Minimum Quantity Lubrication) could reach the effect corresponding to wet cutting at specific cutting parameters and showed great potential to replace traditional lubrication method.
Experimental Study on Heat Transfer Effect of Heat Pipe Grinding Wheel
Authors: Chen Jia Jia , Fu Yu Can , He Qing Shan , Chen Chen , Zhang Wei
Published: October 2013

High temperature in grinding can cause thermal damage to the workpiece. In order to reduce the grinding zone temperature, a method about enhancing heat transfer based on the rotation heat pipe technology is proposed. In this paper, the heat transfer effect of heat pipe grinding wheel (HPGW) under different conditions such as the rotating speed of grinding wheel, the kinds of working fluid and the film thickness are analyzed. The results show that the HPGW has great superiority of heat transfer under certain conditions.
Electrochemical Impedance Spectroscopic Study on DSSC Sensitized with Begonia malabarica Lam.
Authors: Singh Lakshmi K. , Karlo Tado , Pandey Arvind
Published: October 2013

Electrochemical Impedance Spectroscopic studies of dye sensitized solar cells fabricated usingBegonia malabaricaLam. as sensitizer has been carried out. Various electrochemical parameters such as charge transport resistance at the TiO2/dye/electrolyte interface, recombination resistance, chemical capacitance, transient diffusion coefficient, diffusion length and time constant, were calculated using Diffusion-recombination transmission line model. The evaluation of these parameters provides the underlying charge transport mechanism for the present cell. The reported cell has an efficiency of 1.74 % and fill factor of 45%.