bluuebunny/crossref_metadata_2025 huggingface dataset:
Dynamic Analysis and Experimental Research of Laser Cutting Machines
Authors: Zhang Qing Ping , Wang Zheng Ru , Wang Yan Fang
Published: April 2014

Vibration is one of the most important problems in laser cutting machine tool, which causes the manufacturing errors, also influences the machining accuracy of the parts. Modal analysis can calculate vibration type of structures. The paper presents how to use the powerful FEA software ANSYS to do the modal analysis on laser cutting machine tool and also studies the undamped free vibration on laser cutting machine tool. Finally, the test results and theoretical results were compared to verify the rationality of the modal, these provide theoretical base and conditions for dynamics analysis and optimal design.
Error Modeling Analysis of Face-Gear NC Grinding Machine
Authors: Ming Xing Zu , Wang Wei , Zhao Lei , Li Man De
Published: April 2014

Based on the multi-body system theories and used the homogeneous coordinate transform. Systematically analyzed the geometric error and thermal error of face gear NC grinding machine. Established the face gear NC grinding machine of grinding mathematical model of comprehensive error according with the mechanism grinding errors,To provide a theoretical basis of the error modeling analysis and the error compensation on NC grinding Machine Tool of face-gear.
Estimation of Failure Probability for Bearing and its Applications in the Case of Zero-Failure Data
Authors: Han Ming
Published: April 2014

This paper introduces a new method, named E-Bayesian estimation method, to estimate failure probability. In the case of zero-failure data, the definition of E-Bayesian estimation of failure probability is provided; moreover, the formulas of E-Bayesian estimation and hierarchical Bayesian estimation and the property of E-Bayesian estimation of the failure probability are also provided. For the estimate failure probability, in the following sections we will see simple the E-Bayesian estimation method is method than hierarchical Bayesian estimation method. Finally, the calculated results of bearing show that the proposed method is feasible and convenient in engineering application.
Development of NdFeB Permanent Magnet Generator
Authors: Tao Rui Min
Published: April 2014

Simple permanent magnet synchronous motor has the structure of reliable operation, small size, light weight, high efficiency, flexible shape and size and other characteristics. The pole surface of the rotor core is composed of several small magnet block arrays, spacing, width, height, and the magnet block arrays of magnetic blocks relationship between modulations. This paper introduces a development of NdFeB permanent magnet generator. Rotor structure of high-strength permanent magnet synchronous generator by the central shaft, attached to the core and its outer surface two pairs of circular arc-shaped magnets. The design of structures of the key components is demonstrated and the experimental results show the good performance of the generator.
Calculation Reactivity Degree for Axial Low-Account Turbines with Small Emergence Angles of Nozzle Devices
Authors: Fershalov Mikhail Yu. , Fershalov Andrey Yu. , Fershalov Juriy Yu.
Published: April 2014

This paper presents the possibility of constructing a mathematical regression model for the reactivity degree of turbine stages (with the nozzle exit angles 5 ° ... 9 ° and a diameter of 0.17 m) depending on the constructed and model factors that have the greatest impact on the function value.
The Structure Design of Product Equipment for the Rigid PVC Crusting-Foam Plate
Authors: Hu Xiao Zhen
Published: April 2014

Through deeply research and analysis the extruding technology of PVC crusting-foam plate, several main equipments of the production line system such as extruder power transmission system, machine barrel, screw, cooling stereotypes system and traction cutting system are designed. The drawings of all components and parts are drawn by using AutoCAD and Pro/E soft. After the production line assembled, some related experiments, measurement and analysis are completed, and the results show that the quality of PVC plates produced by our production line attained to technical level of imported products.
Dynamic Research of a Kind of Morse CVT Input Mechanism and Parameters Optimization
Authors: Chen Qin Hong , Sun Dong Ming
Published: April 2014

Dynamic simulation study on Morse CVT input mechanism was established by using software Adams, and it can get curves of displacement, velocity and acceleration of each bar and the torque of input mechanisms output in order to research its dynamic characteristics. This method is suitable for dynamic simulation of connecting rod mechanism, meanwhile it is easy to do optimal design by amending corresponding simulation parameter.
Experimental Studies on Triple-Chamber Piezoelectric Pump with Triple Vibrators under Different Working Modes
Authors: Han Bing , Zhang Zhong Hua , Wang Shu Yun , Kan Jun Wu , Ma Ze Hui , Zhu Hang Kai
Published: April 2014

The structure and working principle of serial-connection 3-chamber PZT pump was introduced, and the output performance of the PZT pump was analyzed under different working modes. The pump was tested, respectively, first with each of the three actuators at different location being actuated solely, and then with random two of the three actuators at different location being actuated (in anti-phase) synchronously. The test results show that changing the driving strategy can change the output performance of the piezoelectric pump, with the structural parameters, working parameters and connection Strategy determined. At a voltage of 150 V, the maximal flowrate and optimal working frequencies for the pump under working mode of left, middle, right chambers actuated solely are 9/7.5/11 ml/min and 260/380/720 Hz respectively. The maximal flowrate and the optimal working frequency for the pump under working mode of left and middle chambers/middle and right chambers actuated synchronously are 17/28 ml/min and 460/600 Hz respectively.
Experimental Study on a Piezoelectric Energy Generator with Support Device Excited by Rotating Magnets
Authors: Fu Jia Wei , Wang Shu Yun , Kan Jun Wu , Huang Fang Sheng , Han Bing , Mao Kai Feng , Fan Chun Tao
Published: April 2014

Introduce a piezoelectric energy generator (PEG) with support device excited by the magnetic coupling force between rotating magnets fixed on a rotator and nickel plate fixed on a piezo-beam. The influence of magnetic force (number of the magnets), rotating speed and the work condition of the piezo-beam (with support device or free condition) on energy generation of the PEG was investigated experimentally. The research results show that there are several optimal rotating speeds for the PEG to achieve peak voltage at speed range of 0 to 1200r/min. Under the distance of rotating magnets and the piezo-beam is given, the peak voltages rise with the increasing of rotating magnets number and rotating speed.The maximum peek voltages from the PEG with 2/3/4 rotating magnets fixed on the rotator are 14.4/18.6/20.2V respectively and optimal rotating speeds are 660/456/348r/min. The support device makes optimal rotating speeds move backward, exerts great influence on the rising phases of the peak voltages, prevents piezo-beam from deforming excessively and improve the reliability of PEG.
Two Load Distribution Measurement Methods of Single-Lap Composite Joints
Authors: Xu Zhi Xiang
Published: April 2014

Load distribution is a precondition for strength predictions of multi-bolt composite joints and thus accurate load distribution measurement methods are required. Here two improved methods that strain gauge belts and improved instrumented fasteners are adopted to test the load distribution of single-lap three-bolt composite joints. Although the strain gauge belt can eliminate some errors induced by the manual mounting, it results in rather large errors relative to the theoretical spring model solution. In comparison with the strain gauge belt, the load transfer ratios obtained from improved instrumented fasteners are closer to the theoretical solutions and smaller errors can be obtained, which offers powerful evidence for the applicability of the improved instrumented fasteners to the load distribution measurement of single-lap multi-bolt composite joints.
A Wave Power Device Based on the Principle of the Connecting Rod’s Transmission
Authors: Zhu Guo Liang , Zhang Yan Jun , Zhu Feng
Published: April 2014

The current structure of the world energy system is in transition, the traditional methods have been unable to meet human's requirements to energy, and the collection and utilization of new energy sources have become a very promising research directions, such as solar energy, tidal energy, wind energy, etc. China's energy structure exists many problems; therefore we must vigorously develop renewable energy technologies. This article briefly discusses the issues of China's energy structure and the potential of wave energy, also introduces an effective use of sea wave energy devices, and analyses its structure, working principle and efficiency.
Feature Analysis for Driller Trip Operation Using AC Variable Frequency Motor
Authors: Yin Xiao Li , Fan Cheng Zhou , Liu Zhen Xing
Published: April 2014

This paper analyzed the kinematical and mechanical feature of the trip operation for the 03A driller based on the dynamic brake theory of AC variable frequency motor. The moving pattern of the strip operation and the variable information of the load in winch roller were mastered. We checked the safety coefficient of the winch brake and put forward the suggestions on the safe operation for AC variable frequency controlled driller. This paper is very important for promoting the application of AC frequency technology in drillers.
Functional Availability Modelling of CNC Machine Tools
Authors: Li Xiao Bing , Gao Jun , Zhang Zheng , Zhu Xiao Cui
Published: April 2014

A new method for calculating the instantaneous availability was proposed based on Functional Data Analysis method. It introduced the Quadratic Bernstein Polynomial into the smoothing method firstly for the reliability which estimated by median rank method and estimated the fitting parameters by least square method. Then, under the assumption that the maintenance difficult of the CNCs was decreasing over the work time, chosen the appropriate smoothing basis function based on the trend after the time section adjustment for the estimated maintainability value. The Fourier basis system and the non-linear least squares were selected for the maintainability function smoothing method and the fitting parameters. Finally, the instantaneous availability model of CNCs was built based on the functional linear regression method, and a case example of 15 CNCs was given.
Mechanism and Suspension Control Study for Spherical Reluctance Motor with Magnetic Levitation
Authors: Xu Shao Hua , Zeng Li
Published: April 2014

This paper presents a novel Multi-Degree-of-Freedom spherical reluctance motor with magnetic levitation, it analyses mechanism of magnetic force and electromagnetic torque that spherical motor generates. Conducted a comprehensive control of the spherical motor and analysis and simulate the results of the suspension control system. The simulation experiments show that the state synchronization suspension control owns high precision and immunity to interference.
Strategy Analysis of Override-Control for Drum Height of Shearers
Authors: Zhang Lei , Yu Xiang , Li Wei
Published: April 2014

Aiming to solve the switch problem between auto-and manual-operation of shearer memory-cut due to variation of coal seam conditions, this paper proposes a method that introduces the strategy of override control to the controlling system of shearer memory-cut. This study also improves the control of hydraulic system for lifting cylinder, and designs an override control system for lifting cylinder of shearer. The procedure for controlling the height adjustment mechanism is thus addressed to offer a new control means for reliable operation of the shearer during operations.
The Research of ASR Strategy for the Spindle Inverter Control in CNC Machine Tool
Authors: Li Fang Yuan
Published: April 2014

It is known for rendering more torque in operation at low speed and suitably attaining high performance dynamic control for the inverter. This paper describes the research of ASR strategy for the spindle inverter control in CNC machine tool. The principles of the vector control and formulas for the coordinate transformation are illustrated. The accuracy of the torque depends on the accuracy of the motor parameters used in the control. So the powerful parameter tuning function should be enabled for all kinds of spindle to run effectively. The response of ASR will be perfect if the switching frequencies is used which is usually constant and set by the user.
F-RBFNN Used for Tuning Parameters of Adaptive PID Control for the Drive Motor of Car Dumper
Authors: Cui Fa Yi , Ma Lei Lei
Published: April 2014

In the current environment of energy saving, dumper run energy efficiently that has great practical significance. The drive motor speed determines the roll-over machine efficiency, with the result that motor speed optimal control using adaptive PID control system. Contrary to the volume of PID control, using neural network online-tuning; On hand of network selection, RBFNN and F-RBFNN are selected. Compared with the classical PID control, the PID control based on F-RBFNN and RBFNN achieve the amount of online tuning the parameters of PID control. Especially, compared with RBFNN, F-RBFNN which combines a fuzzy logic technology and RBFNN is more suitable for real-time nonlinear control of the roll drive motor speed. Because parameters tuning more rapidly and static and dynamic performance and anti-interference ability more powerfully.
Impact on Automotive Body Styling Dust Pollution
Authors: Chen Xiu Jun , Wu Yu Long , Sun Xiao , Wu Shang , Hu Wei Lin
Published: April 2014

Use of aerodynamics, air flow spectrum and gives the car body surface of the vehicle surface pressure distribution of the site prone to dust contamination was analyzed, designed body structure, and reduce eddy current flow separation zone, the body surface can be reduced dust pollution, body structure designed to provide a reference.
Multiple Targets Detection and Acceleration Estimation for Intelligent Transport System
Authors: Li Zhi Gang , Lv Jiang Tao , Wang Qiao Yun
Published: April 2014

For intelligence transportation system,it is necessary to resolve the problems of multiple targets detection and vehicle longitudinal control with high level response capability. False targets can appearance because of mistaking the combination of these beat frequencies of Frequency Modulate continuous wave radar. A novel waveform named double-slope symmetrical saw-tooth wave is proposed and its corresponding algorithm is also introduced to resolve the problem of multiple targets detection for automotive anti-collision radar. About vehicle longitudinal control, the purpose of this paper is to propose new approach to estimating relative acceleration information for vehicle longitudinal control without inter-vehicle communication. Computer simulation results and theoretical analysis proved that the proposed methods are effective and practical for multiple targets detection and acceleration estimation in intelligence transportation system.
Jumping Locomotion and it's Application in Robots – A Review
Authors: Khuong Tran Linh , Gang Zhao , Farid Muhammad , Sun Zhuang Zhi
Published: April 2014

This paper presents an overview of jumping robots and the methods used to stimulate them for their movements to prey something or escape themselves. The locomotion type is generally divided into two groups, i.e. directly actuated and indirectly actuated jumping robots. Three examples from the former and four of later class are analyzed in detail and their structures are presented with self-explained pictures. The advantages and disadvantages of each class are also discussed. On the basis of the analysis, it can be observed that directly actuated jumping robots are having more advantages comparatively and some future work is suggested to eliminate their flaws and make them more reliable.
Kinematics Analysis of Palletizing Robot
Authors: Han Xiu Shu , Tian Qiang
Published: April 2014

Structure analysis on four-bar linkage adopted in four-DOF palletizing robot is done in this paper. In the meanwhile, kinematics analysis of the robot modeled through D-H method, including forward kinematics, inverse kinematics, working space and flexibility, is accomplished. Furthermore, simulation of working space is done by taking advantage of the software MATLAB, and experimental verification of palletizing prototype engine under laboratory environment is also completed, which has demonstrated the feasibility of the robots working space and operational capability.
Platform of Industrial Robot Task Simulation Used in Welding Automation
Authors: Ge Yu Chen , Hu Yun Yan , Wang Jun , Mu Sen
Published: April 2014

Based on the research progress of off-line programming system, propose a virtual manufacturing platform to simulate and monitor industrial robot welding task, by combining motion simulation of three-dimensional models, welding characteristics information-driven and monitoring communications. The platform designed as a three-dimensional solid modeling foreground, with kinematics algorithms and task characteristics as the core, to achieve a common solution that provide jobs simulation ,tatistical information and on-line monitoring. And there is a feasibility analysis of technical means.
Research on Design of Industrial Robot
Authors: Hu Hai Dong , Diao Jin Xia
Published: April 2014

the existing experimental industrial robot systems are introduced in detail in this paper, including hardware description connection parameter settings and circuits, as well as the entire experimental system to complete the task. We also study the acceleration and deceleration algorithm handling robot using the servo robot more stable during operation, positioning more accurate, improve the mechanical hand function during operation, providing convenient cost-effective control system for the entire robot control system.
Experimental Analysis of Dynamic Characteristic for Automatic Tensioner
Authors: Zeng Xiang Kun
Published: April 2014

Experimental method and parameters to investigate the dynamic performances of an automatic tensioner are discussed. Parameters to evaluate the dynamic performances of a tensioner include dynamic stiffness, loss angle and equivalent viscous coefficient. Dynamic stiffness and loss angle can be measured directly, and the equivalent viscous coefficient can be calculated by torque-angular displacement loop which identified with the parameters including dynamic stiffness, loss angle, pre-load torque, pre-load angular displacement, excitation amplitude and excitation frequency. In this paper, the influences of excitation amplitude, excitation frequency and pre-load torque on the dynamic characteristics of tensioner are measured and investigated.
Broadband Microwave Transmission Achieved by Using Engineered Sandwich Materials
Authors: Ghezzo Fabrizia , Yi Xiang , Miao Xi Geng , Ji Chun Lin , Liu Ruo Peng
Published: April 2014

In order to improve the transmission of the energy and broaden the frequency band of an electromagnetic wave in the microwave frequency spectrum propagating through a slab of a polymeric material, we designed an optimized material system where a periodic array of metamaterial unit cells are embedded into a polymeric medium in a sandwich-like configuration. The optimization method targeted the overall size and geometrical characteristics of the metamaterial element that can meet the desired energy transmission requirements given a certain materials thickness and materials dielectric properties. The numerical results conducted on this type of metamaterials in a sandwich-like configuration showed that it is possible to attain a high degree of transparency with broadband characteristics by optimizing the performance of the metamaterials in correspondence of the transmission zeros of the substrate.
Cyclic Pulse and Chaos in an Erbium Doped Fiber Laser
Authors: Yan Sen Lin
Published: April 2014

Cyclic pulse and chaos are produced in an erbium doped fiber laser via modulating the pump in numerical simulation. Cyclic pulsing shows under the case of different conditions. Chaos and dual-cycle are studied. And a route is found from cyclic pulse to chaos with the modulation variable. Effects of the modulation level and frequency, pump, Er-doping concentration and photon lifetime are analyzed on cyclic pulse, respectively. We find three regions of periodic pulsing, unstable periodic pulsing and chaotic pulsing.
Determination of the Crystallographic and Electronic Structure of Cesium Holmium Polyphosphate CsHo(PO3)4 with One-Dimensional Tunnel
Authors: Zhu Jing
Published: April 2014

Solution reaction on the Cs2CO3Ho2O3NH4H2PO4 system at the high temperature led to a new cesium holmium polyphosphate, namely, CsHo (PO3)4. Single-crystal X-ray diffraction analysis shows that the title compound crystallizes in the monoclinic system, space group P21/c, and Z = 4 with the following unit-cell dimensions: a = 8.7598(4), b = 9.1580(4), c = 13.7271(6) Å, β = 100.078(1)°. The structure is a complicated three-dimensional (3D) network constructed by the interconnection of [P4O12]4- anionic chains and isolated HoO8 polyhedra via corner-sharing with 1D tunnels occupied by cesium atoms. The electronic structure, density of states, the chemical bonds, and optical properties have been also performed by density functional theory method.
Influence of Superficial Modification of Steels by Materials with Effect of Memory of the Form on Wear-Fatigue Characteristics at Frictional-Cyclic Loading
Authors: Blednova Zhesfina , Rusinov Peter Olegovich , Stepanenko M.A.
Published: April 2014

The results of a study of the effect of surface modification of steel materials with shape memory effect based on TiNi, TiNiCu, and NiAl on the functional and mechanical properties of the samples are reported. Experimental studies have shown the efficiency of the developed technologies. A substantial increase in wear resistance, and friction durability under cyclic loading was found. It is shown that the most universal characteristic of wear-fatigue properties is adaptability, which is determined by the multi-fractal structure of the parameterization.
Effect of Packaging Materials on the Reliability of LED Modules under High Temperature Aging Test
Authors: Xiang Wen Jing , Nie Lei , Li Hua Jing , Huang Fei
Published: April 2014

Phosphor and silicone are common used packaging materials in LED fabrication and have great influence on the reliability of LED modules. In order to understand the effect of these materials, test LED samples were prepared with different sets of packaging materials. An aging test at a constant temperature of 125°C was performed to discover the failure process. The results of aging test shown that the luminance of all samples fell obviously. But the luminance decrease of samples without phosphor and silicone was the least. As to other samples, the carbonization of silicone and the consequent bubbles reduced the luminance rapidly. And the phosphor had the similar influence on the luminance. If phosphor and silicone were used at the same time, the luminance would reduce quickly and then the modules would fail.
Controllable Synthesis of ZnO Nanostructures via Template-Free Electrochemical Deposition at Low Temperature and their Optical Properties
Authors: Duan Jun Hong , Sun Jian Xing
Published: April 2014

We report template-free electrochemical deposition method for preparing ZnO nanostructures arrays on indium tin oxides (ITO) glass substrate. Multiform ZnO nanostructures, such as nanotubes, nanorods with tower-like tips, cone-like tips and groove-like tips, are controllably synthesized at 60 °C, which is lower compared with the prepared temperatures of reported works. The results of XRD indicate the wurtzite ZnO nanostructures are single-crystalline and grow along the c-axis perpendicularly on the substrate. These findings have potential for the growth of high-quality ZnO nanostructures arrays and device applications.
Fiber Materials AC Impedance Spectroscopy and its Application
Authors: Li Xiao Feng , Pan Xiang Gao
Published: April 2014

This article presents a recent study on the behavior of impedance versus frequency of fiber materials. When applying a constant amplitude, it was experimentally observed that the impedance of fiber materials first dropped steeply and then retained in a stable state being followed by a rapid increase with increasing inspiriting signal frequency. The overall impedance versus frequency curve revealed a bathtub-like shape. This behavior is therefore defined as bathtub phenomenon of fiber alternating current (AC) electric conductance. Analysis of the bathtub phenomenon, by using the circuit theory and medium polarization theory, revealed that there exist four different kinds of current in a fiber material when it is exposed to an AC electric field, viz., absorbing current, conductance current, charging current and superficial current. The study showed that this phenomenon is well consistent with and can be evaluated by the medium polarize theory. Understanding of the bathtub effect of fiber AC electric conductance provides a theoretical basis for development of a breaking-through solution to resolve many challenges of conventional impedance technique, such as greatness test error and electrode polarization, etc. The results of this research can be applied to the technology development of novel equipment design for the quick fiber moisture test.
A Method for the Prediction of Fatigue Life of Notched Metallic Material
Authors: Lin Xin
Published: April 2014

The traditional methods for the prediction of fatigue life of metallic material consider only the two processes of fatigue initiation and fatigue cracking, while the process from fatigue cracking to breaking has been neglected. This paper provides one new method of estimating the fatigue life of under-constant-amplitude loading spectrum---non-local gradient damage enhancement model method. Based on the finite element procedure and the partial damage model, this method inserts the non-local strain's definition formula into the loading function and damage rate increment formula. From this method, the non-partial gradient enhancement damage model is obtained. In this model, the material’s microscopic criterion factor and the material’s damage criterion have been considered, the process of endurance failure is also considered. Thus, the insufficiency of traditional research techniques is effectively avoided, the actual effect analysis of metallic material is more reasonable, and the actual operating mode is been conformed to.
Effect of High Strain Rate on Adiabatic Shear Sensitivity and Microstructures in Pure Titanium
Authors: Wang Tong Bo , Li Bo Long , Li Mian , Nie Zuo-Ren
Published: April 2014

As a model material, commercial pure titanium was rolled to plates with different dislocation boundaries. The dynamic mechanical response of Ti specimen was analyzed during impacted with Split Hopkinson Pressure Bar (SHPB) at different strain rates, and microstructure evolution was investigated using optical microscopy and transmission electron microscopy. It was found that adiabatic shear sensitivity was decreased with increasing strain rates for all as-annealed, 25% and 50% cold rolled states. To the contrary, for 70% cold rolled state the adiabatic shear sensitivity was increased with increasing strain rates. The microstructure of adiabatic shear bands (ASBs) were developed from elongation morphology to fine equiaxed grains in the specimens of 25% cold rolled state, and ASBs became broader with increasing strain rate.
Effect of Notch Radius on the Thermal Fatigue Property of a New Guide Vane Materials
Authors: Xia Peng Cheng , Han Guan Peng , Xie Kun
Published: April 2014

Thermal fatigue property of a directionally solidified nickel-base superalloy with different notch radius was studied. The results show that cycle numbers of crack initiation increase and resistance of thermal fatigue decreases with the rise of notch radius at the upper temperature of 1050°C. Thermal fatigue crack initiates at carbide or oxidized cavity. The join of oxidized cavity makes crack propagate. The propagation rate lowers with the increasing notch radius. Crack propagation direction is along <110> direction in {111} plane. The stress concentration drops and thermal fatigue property improves with the increase of notched radius.
Modal Analysis of Crankshaft under Multi-Speed
Authors: Xu Yan Ming , Wang Ran Ran , Teng Xian Bin , Ge Tao
Published: April 2014

In the process of calculating the crankshaft frequency and vibration mode, free mode is always applied for the crankshaft modal analysis. Considering the effect of centrifugal force generated by the rotation to the crankshaft frequency and vibration mode, the frequency and vibration mode of multi-speed cases are calculated, and compared, which fully shows the vibration situation of the crankshaft in the process of actual working situations, the results match actual situation.
Effects of Casting Temperature on as Cast Microstructure and Tensile Properties of AS31-Sr Alloy
Authors: Wang Jin Wei , Zhou Ji Xue , Tang Shou Qiu , Chu Fu Min , Yang Yuan Sheng
Published: April 2014

Casting temperature has important influence on microstructure and tensile properties of casting products. Effects of different casting temperatures (670°C, 700°C, 730°C and 760°C) on as cast microstructure and tensile properties both at ambient temperature and elevated temperature of AS31-0.1%Sr (mass fraction) alloy were studied.The experimental results show that there exist polyhedral shape, fine fibers shape and a few Chinese script Mg2Si particles in AS31-0.1%Sr alloys. The grains at the casting temperature of 700°C are finest. The ultimate strength,yield strength and elongation at both ambient temperature and 150°C first increase when the casting temperature increases from 670°C to 700°C and then decrease with the casting temperature continuously increasing to 760°C.
Flow Behavior and Processing Map of Mg-4Al-3Ca-1.5Zn-1Nd-0.2Mn Magnesium Alloy
Authors: Chen Gang , Chen Wei , Zhang Guo Wei , Zhai Jing , Ma Li
Published: April 2014

Compression tests of Mg-4Al-3Ca-1.5Zn-1Nd-0.2Mn Magnesium alloy as-extruded had been performed in the compression temperature range from 200°C to 350°C and the strain rate range from 0.001 s1 to 1 s1 and the flow stress data obtained from the tests were used to develop the power dissipation map, instability map and processing map. The optimum parameters for hot working of the alloy had been determined. According to the processing maps, the most optimal temperature range is 280°C to 350°C and most optimal strain rate range is 0.001 S-1 to 1 S-1.
Formation Pathway of CuInSe2 through Solvothermal Route
Authors: Zhang Jian Fei , Peng Xiao Li , Guo Wen Bin , Zhang Shu , Xiang Yong
Published: April 2014

CuInSe2 (CIS) is a promising material for thin film solar cell applications. In this work, CIS powders have been synthesized by solvothermal route at different reaction time. X-ray diffraction patterns and Raman spectra of the products reveal that the optimal reaction time is 36 h at 200 °C in order to obtain pure CIS phase. SEM images show an irregular morphology of synthesized CIS material. The formation pathway of CIS has also been studied. Cu-Se compounds are formed at the beginning of the reaction, which act as an important intermediate for the formation of CIS products. This result is not consistent with the reported mechanism.
Impact Performance of ZnAl27Cu2.5MgMn Alloy from Room Temperature to 250°C
Authors: Kang Ming Long , Hu Wu , Zeng Jian Min
Published: April 2014

The impact performance of ZnAl27Cu2.5MgMn alloy from room Temperature to 2500 °C
has been investigated by pendulum impact testing. The surface morphology of impact fracture is observed by scan electron microscope (SEM). The results indicate that impact energy of the alloy decreases as the temperature increases when the temperatures are lower than 100°C. Between 100°C and 200°C, impact energy increases as the temperature increases. And when the temperature exceeds 250°C, impact energy decreases dramatically. Impact energy gets to the maximum at room temperature. Impact behavior of the alloy can be evaluated by the width of impact spectrum curve. The wider the peak of impact spectrum curve, the higher the impact toughness. Whereas impact toughness is worse if peak is narrow.
Making Non-Dendritic Structure via Modified Cooling Slope Technique
Authors: Chen Y.T. , Tsao Chi , Chiang C.H.
Published: April 2014

The cooling slope technique has been developed in recent years, which controls the nucleation and growth of the primary grains during solidification to achieve fine and non-dendritic microstructures. In this study, A356 Al alloys were processed through a modified cooling slope technique to obtain fine, non-dendritic microstructures, in which the cooling rate of the cast crucible was controlled. Three process parameters, namely pouring temperature, inclined slope angle, and the cooling rate of the cast crucible, were varied during the processing. The cooling slope was water-cooled with a constant water flow rate. The solid fraction and the size distributions of the primary grains along the vertical and horizontal positions of the cast ingots were measured individually. The macro-segregation was examined in terms of the distribution of the solid fraction. The yields of the ingots were calculated for studying the efficiency of the cooling slope technique. The effects of the three process parameters on the microstructures, macro-segregation, and yields were studied by the Taguchi method.
Metallic Coatings: Al-Zn Alloys
Authors: Alshmri F.
Published: April 2014

Steel sheet has one major drawback, it is attacked by moisture at low temperatures and oxygen at high temperatures. Fortunately, coatings can provide protection to steel sheet from corrosion. Aluminum and aluminum zinc coatings can be applied by different methods. These are chemical vapor deposition coating (CVD), slurry coating, vacuum coating, spray coating, cladding, electroplating, electrophoresis, diffusion coatings, cementation, calorizing and hot dipping. This paper aims at providing a survey of these processes.
Relationship between Creep Crack Propagation Rates of P92 Steel and Welding HAZ and High Temperature Creep Fracture Parameter C* Based on Reference Stress Method
Authors: Wang Li Xin , Sun Chang Ming , Wang Yan Bo , Xu Lian Yong
Published: April 2014

Uniaxial creep tests on micro-regions of P92 steel base metal and welding HAZ specimens were carried out at 923 K and under different stress levels. The creep equation of index of B and n was obtained from the test data fitted by using least square method. Then, creep crack growth tests based on the reference stress method on P92 steel base metal and welding HAZ compact tensile samples were carried out at 923 K and under stress intensity factor K of 18 MPa·m1/2. From the calculated and experimental data, it was found that a good relationship existed between the creep crack growth rate da/dc and high temperature creep fracture parameter C*. The reference stress method was verified to calculate the C* of compact tension specimens and can predict the creep crack growth rate of the P92 steel base metal and welding HAZ materials under steady state creep conditions. At the same time, high temperature defect evaluation parameters of D0 and Φ were obtained by fitting the linear parts in the relation curves using the log-log method. This study provides tests data on the defects evaluation and life prediction of P92 steel welding materials.
Research of the Factors which Influence the Corrosion of Defective Stainless Steel Funnel
Authors: Yang Yong Min , Zhao Ke Xin , Chen Ze Peng
Published: April 2014

Stainless steel products are used in some building for excellent performance. But actually using in complex environment and influencing by several factors, the products may be eroded. The objective of this study was to account for the cause of the corrosion of the submitted funnel sample. In general, the approach is to formulate and conduct a series of laboratory tests, and interpret the results. Based on the findings, corrosion of the submitted stainless steel funnel could be attributed to three factors, such as material factor, site condition and corrosion.
The Characteristic of Microstructures and Mechanical Properties of a Cu-Ag In Situ Composite Material
Authors: Xie Guo Liang , Wang Qiang Song , Guo Qing Miao , Mi Xu Jun , Xiong Bai Qing
Published: April 2014

A Cu-24 wt % Ag composite alloy is prepared to reveal the evolutions of microstructures, mechanical properties and textures formed by cold rolling. A typical alternating distribution of Cu and Ag phase layers is observed, which becomes much finer with increasing cold rolling reduction. Copper texture ((112)<11-1> texture) and Goss texture ((110)<001> texture) with high intensities are found in the Cu phase of cold rolled samples. Ag phase containing strong Goss texture and weak Brass texture are observed, quite different from the case in cold rolled pure Ag. Significant change of textures, from the Goss texture to (111) textures with increasing rolling reduction, has been found of Ag phase. The strengthening mechanism of this Cu-Ag composite is described by a equation similar to the HallPetch relationship, the fitted results based on which shows good agreement with the experimental data when the layer thickness is lower than 100-200 nm.
The Control of Carbon Content in Sintering Process of Tungsten Steel
Authors: Chen Yong Zhi , He Wei Feng , Wu Peng , Yang Yu Hui , Ye Jing
Published: April 2014

The optimal control of carbon content is one of the most important factors of excellent properties of tungsten steel material. The control of carbon content in tungsten steel materials could be started from several ways. This paper discusses the control of carbon content of tungsten steel material in sintering process. In this paper, that is the main measure to control the carbon content in the sintering process: The control of balance between hydrogen and carbon in pre sintering process; The control of balance between carbon and oxygen in vacuum sintering.
Perforation of Aluminum Plates with Ogive-Nose Projectiles Using Axisymmetric Smoothed Particle Hydrodynamics
Authors: Sun Wei Hai , Ju Gui Ling , Wang Li Jun , Yang Ban Quan , Pan Jing Wen
Published: April 2014

The 2D axisymmetric smoothed particle hydrodynamics (ASPH) has been adopted to study the perforation of AA5083-H116 aluminum plates with ogive-nose hard steel projectiles. The deceleration history curves of the projectile by the ASPH were presented for three impact conditions. Impact vs. residual velocity curves were constructed and the ballistic limit velocity was determined. The computational residual velocities and the ballistic limit velocities from the ASPH agree well with available experimental data. The study shows that the ASPH is able to emulate the perforation of aluminum plates as observed in the experimental investigations of high velocity impact.
Assessment of PBE0 Calculation of C-NO2 Bond Dissociation Energies for Nitroaromatic System
Authors: Su Xin Fang , Huang Wei , Wu Hai Ying
Published: April 2014

Density functional theory (DFT) is used to calculate the C-NO2 bond dissociation energies (BDEs) in nitrobenzene; 3-amino-nitrobenze; 4-amino-nitrobenze; 1,3-dinitrobenzene; 1,4-dinitrobenzene; 2-methyl-nitrobenzene; 4-methyl-nitrobenzene and 1,3,5-trinitrobenzene nitroaromatic molecular system. B3P86 and PBE0 methods in combination with 6-31G** and 6-311G** basis sets are employed. Comparison between the computational results and the experimental values reveals that the calculated C-NO2 bond BDEs can be improved from B3P86 to PBE0 functional. Level of theory employing PBE0/6-311G** is found to be sufficiently reliable to compute BDEs of C-NO2 bond for nitroaromatic molecules with an average absolute error of 0.98 kcal mol-1.
Characterization of Radome Materials Comprising LTCC-Derived FSS on a Quartz Glass Plate
Authors: Miao Xi Geng , Feng Qing Wen , Ghezzo Fabrizia , Fang Xiao Wei , Yue Yu Tao , Zhao Zhi Ya , Liu Ruo Peng
Published: April 2014

Frequency selective surfaces (FSS) and recent metamaterials (MTM) have shown unique electromagnetic characteristics and are of potential benefits for radome applications. To make the radomes/windows high-temperature resistant, the substrates of the frequency selective surfaces or metamaterials should be made of ceramic/glass-based materials of a low dielectric constant and a low loss tangent. However, fabricating ceramic/glass-based FSS or MTM is always challenging. In this paper, a constrained low-temperature co-fired ceramic (LTCC) technique was used to produce quartz glass-based radome material consisting of a frequency selective surface (FSs) layer embedded in a surface laminate. Due to the constrained sintering shrinkage, the geometry and the dimensions of the unit cells of the FSs were not subjected to significant variations and thus the measured electromagnetic (EM) wave transmission spectra matched those of the computer simulation results quite well. This preliminary work marks the beginning of our long-term efforts toward the goal of achieving high-temperature resistant, highly electromagnetic wave transparent, as well as carefullydesigned and fabricated radome materials.
On the Possibility of Neglecting the Coupled-Mode Oscillations of a Single-Mass Dynamic System under Non-Steady Kinematic Excitations
Authors: Melnikov Boris E. , Khazieva Lina F.
Published: April 2014

In the paper was examined the impact of biconnectivity of oscillations of single-mass system on the dynamic factor under unsteady dynamic impact.
Investigation on Microwave Property of Fe/Co Mixed Powders
Authors: Zeng Zhao Yang , Lv Zhen Jian , Ji Xing Wei , Lu Ming
Published: April 2014

For the purse of improving the microwave absorption ability of carbonyl iron, Co power was chosen as additions to add into the sample. Both analyze and measurement proved that the addition of Co power effectively decreased the conductivity, while not obviously destroyed the magnetic property of the sample. In this way, the addition of Co power improved the sample surface matching effect, and correspondingly, the absorption ability is increased.
Analysis and Simulation of UAV Aircraft Flight Dynamics
Authors: Mohammed Tariq O. , Elkhmri Naser M. , AboBakr Hamza
Published: April 2014

The objective of the present work is to evaluate the static and dynamic stability of the Flying Wing Unmanned Aircraft Vehicle (UAV) model using the Tornado software. The longitudinal and the lateral-directional aerodynamics were studied using the model with incompressible flow, asymmetric, conditions. The stability coefficients were calculated and give proof that the aircraft is statically stable. Using the stability coefficients, the longitudinal and lateral-directional equations of motion were written to evaluate the dynamic stability of the vehicle. Good flying qualities were obtained, rating in Level 1 for the Cooper and Harper scale.
Performance of Emulsified Asphalt Full Thickness Cold Recycling Subgrade Materials
Authors: Li Jun Xiao , Yin Xiao Bo , Yuan Jian , Zang Hechao , Hao Zong Rui
Published: April 2014

Full thickness cold recycling subgrade materials were prepared by cement-emulsified asphalt solidified RAP and stabilized soil.The effect of adding amount of emulsified asphalts change on unconfined compressive strength, indirect tensile strength and water stability of cold recycled mixtures with different ratios was studied,and the mechanism of action of cement and emulsified asphalt in the mixtures was analysised via microscopic test. The results show that a proper addition of emulsified asphalt can improve the performance of cold recycled mixtures and the best emulsified asphalt mixing content is 3%. Microscopic test indicate that the cement hydration products space network structure interfinger with the emulsified asphalt network structure, so the cold recycled mixture tightly coupled to a semi-rigid whole, and the mixtures strength can form and develop.
Preparation of Nano-SiO2 Particles Modified by Fluorine Silane Coupling Agent
Authors: Wei Xiao Li , Zhang Fa Xing
Published: April 2014

In this paper nanoSiO2 particles were prepared with the surface grafted fluorine coupling agents and double bond by using surface modification technology. Dispersion effect of nanoSiO2 particles were studied in different solvents ultrasound cavitation. Test results showed in infrared spectroscopy, TEM and laser particle size distribution analyzer that both F8261 and KH-570 have been grafted onto the surface of nanoSiO2 , particle size and distribution of nanoSiO2 after modified by the two coupling agent became smaller and more narrow; Tg-DSC analysis showed that when the amount of of the coupling agent is up to 10%, fluorine coupling agent and double bond grafted onto surface of nanoSiO2 particles reach the saturation.
Ring-Opening Polymerization of Lactide Using Aluminum Salen-Type Initiators
Authors: Zhang Qing , Tian Jing , Cao Zhi Qi , Xu Ru Xia , Sun Zhen Zhen , Wang Xiao Juan , Cui Jian Jie , Li Jun Ni
Published: April 2014

In this investigation, Schiff bases aluminum complex was synthesized and used as the initiator in the polymerization of D,L-lactide. The aluminum complex was characterized by infrared spectroscopy (IR), and nuclear magnetic resonance spectroscopy (NMR). The influences of different factors, including reaction time, reaction temperature, and the ratio of D, L-lactide/Al3+ on the synthesis of polylactide were described. The results showed that Schiff bases aluminum complex could be successfully applied in the ring opening polymerization. The optimum condition of the ring opening polymerization of D,L-lactide, which included D,L-lactide/Al3+ (mol/mol) ratio of 250, reaction temperature of 120 °C, and reaction time of 16 hours.
Structure Design and Manufacturing of the Composite Blade for the Icing Wind Tunnel
Authors: Yu Ze Bin , Liu Zheng Chong , Leng Shuang , Cai Yong
Published: April 2014

The structure design and manufacturing of the fan blade ware researched based on large-scale temperature change, high-revolution, multi-constraint conditions, high-fidelity profile and so on. The numerical modeling was performed in MSC, including strength, stiffness as well as eigenfrequency analysis, optimized to layer thickness and mass of blade. The resin transfer molding (RTM) process was used to ensure the blade geometrical tolerance. Multiform tests were provided to verify that the design and manufacturing is reasonable and the blade satisfies with application requirement.
Study on Fiber Reinforced Composite Materials with Wushu Cultural Heritage
Authors: Chen Wei , Liu Chao
Published: April 2014

This paper analyzes the properties of fibre reinforced composite materials, which are used for the improvement or reform of Wushu equipment so as to promote Wushu cultural heritage. Reinforced composite materials can help promote the reform or improvement Wushu protective gear and target, Wushu performance or fitness appliances, expressing Wushu moves better and highlighting its artistic attribute . Besides, this paper also expounds strengthening the popularization of Wushu to provide help for improving the traditional Wushu conditions as well as strong support for the development of Wushu athletics and Wushu standardization.