bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of SBA-15 within Short Reaction Time
Authors: Zhang Jing , Mi Long , Yan Shi
Published: July 2013

Mesoporous molecular sieves SBA-15 was synthesized by using tetraethyl orthosilicate (TEOS) as silica source and pluronic 123 (EO20PO70EO20) as a template within short reaction time (6 hours) in acidic media. The influences of the different synthesis parameters such as crystallized time and crystallized condition was investigated .The resultant samples were characterized through XRD and Nitrogen adsorption. The results showed the well ordering channels SBA-15 can be synthesized under air atmosphere within 6 hours, and the best proportion could be obtained with 1 TEOS: 0.010 P123:2.17 HCl:231 H2O. After heating at 1273K for 2 hours and boiling at 373K for 24 hours, the calcined SBA-15 was proved there is well stability.
Properties of High-Quality LaAlO3 Film Deposited by In Situ Plasma-Enhanced-Atomic-Layer-Deposition
Authors: Cao Duo , Cheng Xin Hong , Jia Ting Ting , Xu Da Wei , Zheng Li , Wang Zhong Jian , Xia Chao , Yu Yue Hui
Published: July 2013

Plasma enhanced atomic layer deposition (PEALD) method can decrease film growing temperature, and allow in-situ plasma treatment. LaAlO3 films were deposited with PEALD at 180°C. High resolution transmission electron microscopy (HRTEM) results exhibited amorphous microstructure of both films even after rapid thermal annealing (RTA) at 800°C. X-ray photoelectron spectroscopy (XPS) spectra suggested that the valence-band offset between the LaAlO3 film and the substrate was 3.3 eV. The electrical experimental results indicated that the leakage current densities were 0.10mA/cm2 and 0.03mA/cm2 respectively at a gate bias of |Vg-Vfb|=1V and the equivalent oxide thicknesses (EOT) of them were 1.2 nm and 1.4 nm, respectively. The densities of interfacial states were calculated to be 1.70×1012eV-1cm-2 and 1.09×1012eV-1cm-2, respectively.
Electronic Structures and Magnetic Properties in Ti-Doped ZnO
Authors: Chen Yi Fei , Song Qing Gong , Li Rao
Published: July 2013

Using first-principles calculations based on density functional theory, we investigated systematically the electronic structures and magnetic properties of Ti-doped ZnO. The results indicate that Ti doped ZnO prefers the ferromagnetic ground state and shows a metallic behavior. We found that Ti-doped ZnO is a weak ferromagnet and FM exchange interaction is short-ranged. In addition, it has been found that Ti atoms have a tendency of cluster together around O atoms.
Microstructure and Surface Oxides of Cutting Tool Material on 9SiCr4
Authors: Fu Ya Bo , Chen Xue Lin
Published: July 2013

The cutting tool material of 9SiCr4 is widely applied in the manufacturing. The paper studied the microstructure and surface oxides on 9SiCr4 by SEM and XRD. through the studying of microstructure, paper find that basal body- Fe is distributed with the lamellar shape on 4-9 μm, and FeC3- called cementite again and Si distributed with small spherical or elliptical particle shape on 0.5-1μm, and Cr distributed with large spherical or elliptical particle shape on 3-5μm and W distributed with large rod shaped on length 1.5μm and width 0.5μm. Moreover, Surface oxides of 9SiCr4 are NaNO3, Na3H (CO3).2H2O, Fe2O3 and Fe3O4.
Inductively Coupled Plasma Etching of Pt/Ti Electrodes in Cl-Based Plasma
Authors: Zhong Zhi Qin , Yang Cheng Tao , Zhang Guo Jun , Wang Shu Ya , Dai Li Ping
Published: July 2013

Dry etching of Pt/Ti film was carried out using Cl2/Ar plasmas in an inductively coupled plasma (ICP) reactor. The influence of the various process parameters, such as RIE power, ICP power and Cl2/Ar gas mixing ratio, on the etch rate and selectivity of photoresist to Pt/Ti film were investigated systematically and optimized. It was revealed that the etch rate and the selectivity strongly depended on the key process parameters. The etch rate was found to increase dramatically with increasing of RIE power and ICP power. But by changing the ratio of Cl2 to the total gas, the maximum etch rate could be obtained at the proper ratio of 20%. The results also indicated too low or too high RIE power and the Cl2 ratio was detrimental to the selectivity. The optimized parameters of Pt/Ti dry etching for high etch rate and low selectivity of photoresist to Pt/Ti were obtained to be pressure: 10mT, RF power: 250W, ICP power: 0W, Cl2: 8sccm (standard cubic centimeters per minute), Ar: 32sccm.
Simulation of an Explosive Separation Device Used in Aerospace Craft
Authors: Ye Yao Kun , Yan Nan , Ding Feng , Man Jian Feng
Published: July 2013

In order to study the work principle and separation features of an explosive separation device used in aerospace craft, this research establishes a three-dimensional finite element model based on ABAQUS software. Through simulation of separating process, the work principle is made clear, the separation time and maximum separation velocity are respectively 2.4ms and 8.9m/s. Meanwhile, a measurement system is designed for experiment and verifying the simulation results. The tested separation time and maximum separation velocity are respectively 2.8ms and 7.5m/s ,which shows that the proposed finite element model and simulation can provide references for the research and development of explosive separation devices in aerospace crafts, as well, it is also an effective way to analyze and evaluate the feature of explosive separation device.
Preparation and Characterization of Positively Charged Quaternized Chitosan/PEI Composite Nanofiltration Membranes
Authors: Han Run Lin
Published: July 2013

2-Hydroxypropyltrimethyl ammonium chloride chitosan (HACC) with positively charged character was utilized to fabricate the functional layer of the composite NF membrane and reinforced polyetherimide (PEI) ultrafiltration (UF) membrane was used as the support layer. When the composite membrane was prepared under optimized conditions and tested at 0.4 MPa and 10 oC, the flux of the composite NF membrane was about 18 L/m2h and the MgCl2 rejection of it was about 81.6%. The composite membrane showed classical positively charged membrane character which had higher rejection to high valent inorganic salts.
Effects of Film Thickness on Laser Induced Voltage (LIV) of La2/3Ca1/3MnO3:Ag0.05 Thin Films Grown on LaAlO3 Substrates
Authors: Liu Xiang , Yan Yi Zhi , Chen Qing Ming , Zhang Hui , Cao M.G. , Yang Y.A. , Zhang P.X.
Published: July 2013

La2/3Ca1/3MnO3:Ag0.05(LCMO:Ag0.05) thin films were prepared on vicinal cut LaAlO3(LAO) substrates with various film thicknesses by pulsed laser deposition technique (PLD). XRD results show that all the samples are shown along the (00l) orientation in orthorhombic structure with Pbnm space group. While the film thickness is around 450nm, the optimum LIV effects of the epilayer thin film have been obtained. The LIV effects enhancement of the LCMO:Ag0.05 thin films due to the photon scattering effects have been restrained and anisotropic seebeck coefficient improved.
Finite Element Analysis on the Blast Resistant Performance of Multibarrel Tube-Confined Concrete Column in Different Cross-Sections
Authors: Wu Sai , Zhao Jun Hai , Xiong Er Gang
Published: July 2013

Based on the finite element analysis software ANSYS/LS-DYNA, this paper numerically analyzed the dynamic performance of MTCCCs with different cross sections under blast load, followed by the study and comparison on the differences of the detonation wave propagation and failure modes between the columns in circular cross section and square cross section. The results show: The blast resistant performance of the circular component is more superior than the square component for its better aerodynamic shape that can greatly reduce the impact of the detonation wave on the column; The main difference of the failure modes between the circular and square cross-sectional components under blast load lies in the different failure mode of the outer steel tube. The simulation results in this paper can provide some references for the blast resisting design of MTCCCs.
Conical Surface Sealing Performance of Pipe Connection Fits
Authors: Qiu Ming Xing , Wang Jian Jun , Wang Zhen Xing , Li Zhan Ying
Published: July 2013

The conical surface sealing performance of a pipe connection fit (PCF) has been studied by means of an equivalent mechanical model and the contact finite element analysis (FEA). By building an equivalent mechanical model, we studied the basic mechanical relations between the jointing parts, proposed a sealing mechanism, and identified a basic pretension-relaxation-leakage mode occurring in the sealing process of a conical surface PCF. Then we simulated the contact states of the PCF sealing surface using a multi-body elastic contact finite element method (FEM). In addition, the characteristics of the pretension-relaxation-leakage mode were further discussed in terms of the contact forces as well as the contact areas on the sealing surface. These results revealed some fundamental characteristics inherent in the sealing process of conical surface of PCFs, and demonstrated the potentials of the contact FEA in studying PCF sealing performance.
Video Object Detection Algorithm Based on Gaussian Mixture Models
Authors: Fu Zhao Xia , Wang Li Ming
Published: July 2013

The moving object detection of the video image is the basis of sequence image analysis, and it is the research hot issue of today’s foreign and domestic scholars. For detecting the moving object from the scene image in time, a detection algorithm of video moving object based on Gaussian mixture models is proposed in the paper. The pixel values are seen as the combination of the foreground Gaussian distribution and the background Gaussian distribution, and the background estimation and the adaptive background update will be put up. The statistical number of the foreground pixel of the current frame determines whether the light has a larger change, and it combines with the frame-difference method to detect moving object. The experimental results show that the algorithm can quickly and accurately establish the background model and accurately segment the foreground object.
The Optimization of the Pass Structure of Double Regenerative Burner with the Numerical Simulation of Thermal Stress Field
Authors: Jiang Fan Zhi , Kong Jian Yi , Ouyang De Gang
Published: July 2013

In order to solve the problem of cracks of the double regenerative burner, six kinds of low stress pass structures were newly developed and corresponding 3D CAE models were set up. With the FEM numerical simulations of thermal stress field of various combinations of different pass structures and the comparative study, the optimized pass structure that the thermal stress is relatively lower and thus can improve the service life of burner was determined.
Application of Steel Plates on the Retrofitting of Current Reinforced Concrete Coupling Beams
Authors: Bei Cheng , Li Shi Wei , Su Ray K.L.
Published: July 2013

Coupling beams are essential structural elements of reinforced concrete coupled shear wall to resist earthquakes and other lateral loads. But many current reinforced concrete coupling beams are insufficient in resisting lateral loads due to their bad ductility. So a test of retrofitting methods of deep coupling beams with steel plates since their good performance in the ductility and deformation was made to find ways of improving the ductility of the beams, and the results of this retrofitting method prove good because of the incensement of the ductility, deformation and strength of the beams.
Analysis and Simulation of Low Speed Sensorless Vector Control with Two Current Signal Injection Schemes
Authors: Li Yu Dong , Zhou Bo , Liu Ying , Zhao Cheng Liang
Published: July 2013

Two current signal injection methods, the fluctuating high frequency (HF) current signal injection and low frequency (LF) current signal injection, were discussed. The basic principles of rotor position self-sensing using these current signal injection and the key techniques in implementation were presented and the simulation models for sensorless vector control systems of a permanent magnet synchronous motor (PMSM) were established using two proposed rotor position estimation methods. Comparative simulation study of the fluctuating HF current signal injection and LF current signal injection was investigated, and draw the conclusions that the saliency-tracking scheme using fluctuating HF current signal injection possesses simpler configuration and better speed-adjustable performance both in static and dynamic.
Design of Gas On-Line Monitoring System Based on STM32 & Linux
Authors: Guo Shun Jing , Li Jing
Published: July 2013

A new portable gas detect & alarm device which is controlled by Single Chip Micyoco is proposed in this paper, which means the hardware and drivers designation of system uses STM32F103 as its central processing unit and also expounds the detail of software and hardware design. The system communicates with metrical instrument by the RS485 BUS. It can monitor the mine gas in network. It has good man-machine interaction contact surface and can be inserted into intelligence instrument as a general module.
Study on RFID-Based Intelligent Management System for Vehicles
Authors: Xu Su , Teng Wan Li
Published: July 2013

Along with the increase of the number of motor vehicles in urban areas, the relatively backward parking lot management has resulted in many problems such as the difficulty of parking and chaos management. In this paper, a RFID-based vehicle intelligent management system is designed, and its system structure, working flow and software design idea are also introduced in details. This intelligent vehicle management system is cored at ultrahigh RFID (radio frequency identification device), in which legal vehicles are unnecessary to stop in entering and exiting, and also all identification and judgment are automatically implemented by the system from a remote distance.
Study on Multisensor Data Fusion of Ultrasonic Sensor
Authors: Liu Bao Jun
Published: July 2013

Aiming at data fusion of Autonomous car multisensors experiment at many times on distances, a novel fusion method is proposed based on the approach degree and weights. The method calculate mean and variance based on the measured sensors data, Using the maximum and minimum approach degree of this fuzzy set , the approach degree of the measured data from various sensors is processed quantitatively ,eliminating outlier data by Grubbs method, assigned the weights of data measured in the fusion process reasonably , so that the final expression of the data fusion is obtained, thus the data fusion of multisensor is realized.Test results demonstrate that this method can bring higher fusion precision, and more suitable for microcontroller and embedded systems applications.
Design and Error Estimates of Cut Tobacco Feeding by Wind System
Authors: Zhou Xiao Zhong
Published: July 2013

The cut tobacco transporting is the absolutely necessarily important tache, whether the transportation process stability is a direct impact on production quality and manufacturing standards. The wind system is adopted by most tobacco companies because of it caused least disruptive of the cut tobacco structure and the pipe network layout of system is flexible, but the wind system is greater influence by itself, different control methods are caused greater difference of process indicators, for example essence and spice ingredients, moisture proportion and smoke flavor. Based on the above reasons, so we need to design the control method of wind system necessarily, in addition we must checkout the control accuracy opportunely, so that it is satisfied by the actual working conditions.
Research of Microwave Detector Signal Automatic Gain Control
Authors: Wang Ai
Published: July 2013

With the social development and progress of science and technology is constantly updated, the original combination of intelligent switch control method for automatic control of microwave detector signal has been far failed to meet the present demand, we need to study the new technology, this paper to automatically select microwave detector signal gain Research and Implementation of the control method as the research subject, and hope to contribute to a microwave detector signal automatic gain control method study with friends and readers.
Research of Underground Tag's Anti-Collision Algorithm
Authors: Chen Yan Ge , Wang Ya
Published: July 2013

Study of the conflict questions of multiple miners (electronic tag) in the same RF induction area of the underground personnel positioning system. Analyze the Pure Aloha algorithm, Time Slot Aloha algorithm, Dynamic Framed slotted Aloha algorithm based on Binary algorithm. And put forward a kind of mixed anti-collision algorithm through improved.
Hydraulic Cylinder Driving Based on Synergetic Control
Authors: Liu Ya Qiu , Wu Qu , Wang Chun Xiao
Published: July 2013

A controller for hydraulic cylinder driving is designed according to synergetic theory. Based on a cylinder model, the synergetic controller is tested. Simulation results using PI and synergetic control under two kinds of reference input demonstrate that synergetic control is suitable for cylinder driving in MDF hot-pressing because there is no overshoot for tracking. And it is shown that converging speed, affects systems tracking performance.
Resarch of Embedded Web Server in Manufacturing Engineering
Authors: Fan Li Mei
Published: July 2013

Articles submitted Embedded Web Server based on Web management model in Manufacturing Engineering, the main solution is the use of a Web browser to access a large number of non-Inter net equipment under limited resources and processing power, control, and management and other issues. Enabling device networking and intelligent management, field programmable equipment online remote monitoring, management and maintenance functions can be achieved, providing reliable technology for the network intelligent management of industrial production automation systems and smart appliances, supported.
Water Injection Station Design Based on One-For-Several Rotor VVVF Technique
Authors: Chang Yan Rong , Wang Shou Hu , He Ru Xian
Published: July 2013

In the process of oilfield water injection volume of injection allocation often appears with the pump displacement situation does not match; the widespread adoption of stator frequency technology allows the pump displacement and volume of injection allocation phase matching. But the technology in pump class load application speed range is limited, there is still a reflux valve control blind area," turn off undead" problem. One-for-several" rotor frequency Technique in water injection station application solved the control blind area problem, the full realization of the variable frequency close return voltage injection, at the same time, the successful implementation of the slip power efficient feedback. Stable water injection pressure of the system and the electric energy is saved, satisfy the oilfield high efficiency, fine water needs, has a high application value.
Design of External Memory Based on the C8051F02x Microcomputer
Authors: Liu Zhi Jing
Published: July 2013

The C8051F02x microcomputer and its saving structure are introduced, I/O function expanding and connecting are analyzed for its data. The exterior data and the structure of the memory are elaborated with the technique expanding request. Access or expansion of external data memory, external memory interfaces (EMIF). Its data memory address space can be flexibly implemented by the on-chip internal memory can be extended to chip memory. EMIF can be configured as address / data multiplexed or non-multiplexed mode. When big capacity FLASH memorizer is needed, this paper provides a realistic design and methodology for microcomputer and string big capacity FLASH of total line, through the setup and analysis of the SPI of the C8051F02x MCU inner part.
Resonance Analysis of PCB Power-GND Pairs
Authors: Liu Rui , Xiao Dan
Published: July 2013

PCB Power-GND resonance is important in PI design. This article introduces PCB power-ground pairs resonance analysis methods, based on the comparison of theory calculation and simulation in Sigrity PowerSI via one simple example. The relationship between Z simulated parameter and resonance frequency is discussed, additionally, considering about the impact of excitation source impedance, VRM should be modeled as voltage source and drink IC should be modeled as current source to get right simulation results.
Communication Transmission Device Based on New Nano Material
Authors: Lin Huo Yang
Published: July 2013

Nanomaterials is an important part of the whole field of nanoscience and nanotechnology, which involves the structure, properties and applications of nanomaterials, nanomaterials preparation technology and its detection means. All the individual nanoresearch areas, such as nanoelectronics, nanochemistry and nanobiology are all involved in the study of nanomaterials. This article briefly describes the electrical, optical and optoelectronic properties of nanomaterials, and elaborates the application of New nanomaterials in communication transmission, which is designed to strengthen the exchange of learning.
Size Tunable Synthesis of Gold Nanoplates by Gamma Irradiation in Presence of Polydiallyldimethylammonium Chloride as the Capping Agent
Authors: Francis San Ju , Nuwad J. , Gupta Alka , Sainis J.K. , Tewari R. , Gupta Nidhi , Mitra D. , Varshney Lalit
Published: July 2013

A simple gamma irradiation strategy was developed for the synthesis of gold nanoplates by employing polydiallyldimethylammonium chloride (PDDA) as the capping agent. The nanoplates produced had hexagonal, triangular and truncated triangular shapes and the size of the nanoplates could be varied from 500 nm to 5 μm by adjusting the concentration of Au3+ and PDDA in the solution. X-ray diffraction and selected area electron diffraction investigations proved that the nanoplates are single crystals bound by the {111} planes on the top and bottom surfaces. The nanoplates were also characterized by energy dispersive X-ray analysis and X-ray photoelectron spectroscopy.
Evaluation of TiO2 Nanotube Thin Films Fabricated by Anodic Oxidation
Authors: Okumoto Yusuke , Kawakami Ryo , Sato Yuuki , Yoshikado Shinzo
Published: July 2013

Titanium dioxide nanotubes (TNTs) were grown by anodic oxidation of a titanium thin film deposited on an indium tin oxide (ITO) glass substrate. The TNTs were arranged densely and formed a thin film on the ITO substrate. Anodic oxidation was carried out at 550oC in an electrolyte. The inner diameter and tube length of a grown TNT were approximately 15 nm and 0.5 μm, respectively. Several of the TNT tube openings were closed by lids. These lids could be removed by sputter etching for a short time. The crystal structure was non-crystalline. The power conversion efficiency of a dye sensitized solar cell fabricated using the TNT thin film as a negative electrode is much smaller than that fabricated using conventional TiO2 nanoparticle thin films, at present.
Synthesis of U-Type Strontium Hexaferrite by Polymerizable Complex Method
Authors: Kikuchi Takeyuki , Yoshida Shinji , Nakamura Tatsuya , Yamasaki Tohru , Nakanishi Makoto , Fujii Tatsuo , Takada Jun , Ikeda Yasunori
Published: July 2013

Synthesis of U-type hexaferrite was investigated in the various strontium-based systems (Sr-Me-Fe-O system, Me = Co, Zn, Cu, and Ni). Precursors of ferrites were prepared by polymerizable complex method. Sr4Me2Fe36O60 (Me = Co and Zn) U-type hexaferrites were synthesized at the temperature range between 1423 and 1483 K in air. Coercivity of obtained ferrite was decreased with increasing heat treatment temperatures. Cu substitution reduced formation temperature of U-type hexaferrite.
Synthesis of the Sr3Zn2Fe24O41 Z-Type Ferrite by Polymerizable Complex Method
Authors: Tainaka Takuya , Kikuchi Takeyuki , Nakamura Tatsuya , Yamasaki Tohru , Nakanishi Makoto , Fujii Tatsuo , Takada Jun , Ikeda Yasunori
Published: July 2013

Synthesis of Sr3Zn2Fe24O41 Z-type ferrite was investigated. Precursors of ferrite were prepared by polymerizable complex method. Identification of formed phases in the obtained samples and determination of lattice parameters of Z-type ferrite were performed by powder X-ray diffraction (XRD). Single-phase of Sr3Zn2Fe24O41 Z-type ferrite was synthesized by heating at 1463 K for 5hours in air. M-H curve of prepared single-phase Sr3Zn2Fe24O41 Z-type ferrite was measured by using vibrating sample magnetometer (VSM). It was revealed that Sr3Zn2Fe24O41 Z-type ferrite has larger saturation magnetization (23.5 μB/formula unit) than that of Sr3Co2Fe24O41 (22.7 μB/formula unit) and shows characteristic two-step saturation of magnetization as well as Sr3Co2Fe24O41 Z-type ferrite.
Grain Size Dependence of the Microstructure and Dielectric Properties of Potassium Niobate-Barium Titanate Ceramics
Authors: Yamashita Kenta , Fujii Ichiro , Nakashima Kouichi , Kumada Nobuhiro , Kuroiwa Yoshihiro , Takahashi Tetsuhiro , Tsukada Takeo , Wada Satoshi
Published: July 2013

In this study, 0.8 KNbO3(KN) -0.2 BaTiO3(BT) ceramics were prepared using KN powder with the diameter of 100 nm and BT powders with the diameter of 100, 300, or 500 nm. The relative densities were more than 96 % of the theoretical densities of the samples. The dielectric constant of the samples was temperature-stable at temperatures between-50 and 300 °C and it was found that the dielectric constant of the 0.8KN-0.2BT ceramics increased as the BT diameter increased.
Growth and Ferroelectric/Piezoelectric Properties of (K,Na)(Nb,Ta)O3 Ferroelectric Single Crystals
Authors: Hattori Takuya , Kitanaka Yuuki , Noguchi Yuji , Miyayama Masaru
Published: July 2013

Single crystals of (K,Na)Nb1-xTaxO3(KNNT) were grown by the top-seeded solution growth (TSSG) method under high oxygen pressure atmosphere (Po2= 0.9 MPa), and their dielectric properties were investigated along [10cubic(the cubic notation). KNNT single crystals in a composition range of 0x0.65 were successfully obtained. Through the measurements of x-ray diffraction and dielectric properties, we propose a temperature (T)-composition (x) phase diagram in the KNNT system in which a successive phase transition from orthorhombic (Amm2), tetragonal (P4mm) to cubic (Pmm) occurs with increases inTandx.
Influence of Film Texture on Reliability of Sol-Gel Derived PZT Thin-Film Capacitors
Authors: Noguchi Takashi , Sakurai Hideaki , Fujii Jun , Doi Toshihiro , Watanabe Toshiaki , Soyama Nobuyuki
Published: July 2013

Time-dependent dielectric breakdown (TDDB) of lead titanate zirconate (PZT) thin-film capacitors derived by a sol-gel deposition process has been studied. Without any change in heat treatment conditions such as temperature, ramping rate, and keeping time, the films grain size was varied by adding a small amount of organic additive to PZT sol-gel solution for a control of nucleation to form PZT oxide. The reliability was remarkably improved by fabricating interfaces with multi-annealing process, parallel to film surface when the grain size is greater than film thickness, which seems to suppress conductivity of oxygen vacancies.
Dynamic In-Process Stock Based Tool Path Generation for High Surface Finish Rough Machining
Authors: Ding Song Lin , Mo John P.T. , Yang Daniel
Published: July 2013

This paper presents a new tool path generation strategy for rough machining based on the dynamic in-process stock model of the workpiece. Compared to conventional roughing method, the new tool paths result in a better surface finish but consume the same machining time. The cutter locations in the tool path are determined by removing the peak portion of the residual materials on the stock. The geometric information of remaining stocks is updated dynamically in the in-process model once each cutting pass is completed. The overall machining time is no longer than the conventional method since no additional tool paths are added. The proposed method was implemented in Catia and has been validated by simulation and cutting tests with flat end and ball nose cutters on a 3-axis CNC milling machine.
Parameters Optimization and Experimental Study of Aero-Engine Blade in Electrochemical Machining Based on High-Risk Machining Parameter Elimination
Authors: Li Zhi Yong , Niu Zong Wei , Li Li
Published: July 2013

Because the process of blade in electrochemical machining(EMC) can be effected by many factors, such as blade shapes, machining electrical field, electrolyte fluid field and anode electrochemical dissolution, different ECM machining parameters maybe result in great affections on blade machining accuracy. Regard some type of aero-engine blade as research object, a great deal of ECM machining parameter combination which probably result in machining failure can be eliminated based on BP neural network firstly. Furthermore, the optimized ECM machining parameter combination has been discovered. To verify the validity of the optimized ECM parameter combination, a serial of machining experiments have been conducted on an industrial scale ECM machine, and the experiment results demonstrates that the optimized ECM parameter combination not only can satisfy the manufacturing requirements of blade fully but has excellent ECM process stability.
Preparation and Characterization of Nano Zinc Borate/Epoxide Resin Composite
Authors: Gao Ping Qiang , Song Wen Hua , Wang Xing
Published: July 2013

A nano zinc borate wasprepared via coordination homogeneous precipitation method using sodium borate (Na2B4O7•10H2O)and zinc borate nitrate (Zn (NO3)2•6H2O). The characterizations of theas-obtained samples were studied by X-ray diffraction(XRD), Field-emissionscanning electron microscopy (FESEM), Fourier transform infrared spectrum(FTIR) and differential thermal analysis (TG–DTA) It had been found that theproducts had excellent inflaming retarding effect for epoxide resin.
Analysis and Experimental Investigation of Grinding Force in Ultrasonic Vibration Mill-Grinding of Brittle Materials
Authors: Qiao Guo Chao , Dong Guo Jun , Zhou Ming
Published: July 2013

Based on the Kinematic analysis, the indentation fracture mechanics is used to build a force model of ultrasonic vibration mill-grinding. To verify the force model, experiments are carried out for silicon nitride ceramics with various machining parameters, meanwhile grinding forces are measured. Finally, comparison between predicted results with experimental results is presented.
Design of a 5-Axis CNC Machine Tool Applied to Dental Restoration
Authors: Lei Xiao Bao , Xie Feng , Zhao Ji Wen
Published: July 2013

In this work, a 5-axis machine tool used for dental restorations is designed. In view of the fact that its special characteristics of the applications, the mechanical structure and main part of the machine tool have been designed and chosen with careful calculation. The machine tool is equipped with a high speed electro-spindle driven by computerized velocity and can rotate at a maximum speed of 60,000 rpm, which driving unite is equipped with servomotor and optical grating for its better motion precision control. Meanwhile, by using the motion controller card, the machine is controlled with a closed-loop numerical control system. Based on the theory of multi-body system, and through analyzing the matrix of the position transformation and the displacement transformation, a model for positioning errors is put forth for error compensation in programming way. The grinding programs enable exact copies of the object to be fabricated. The satisfactory results show this machine tool has excellent performances.
Design of Acoustic Emission Monitoring System for Defects of Hull Plate
Authors: Xu Zhen Ying , Huang Jun , Cai Yang Yang , Gao Shu Yuan
Published: July 2013

An acoustic emission (AE) monitoring system has been developed for micro cracks of hull plate, which has a human-machine interface (HMI) designed by Labview, with functions of signal acquisition, storage and replay, key parameters extraction. With the powerful signal processing capabilities of MATLAB, defects can be rapidly and accurately located.
Layered Clay Rubber Composites
Authors: Runcy Wilson , Nithin Chandran , Sabu Thomas
Published: July 2013

The field of nanotechnology is one of the most popular areas for current research and development in virtually all technical disciplines. This obviously includes polymer science and technology. In recent year, researchers have been working on a new scale of reinforcement by incorporating a fine dispersion of clay silicatelayers in the polymer matrix to obtain polymer nanocomposites. Nanoscale layered clays, due to their high aspect ratio and high strength, can play an important role in forming effective polymer nanocomposites. Polymer nanocomposites have received much attention due to its large surface area and very high aspect ratio. Polymer nanocomposites especially rubber based nanocomposites is one of the many composite materials in which researchers and engineers have shown great interest due to their potential to be used in critical applications. Polymer layered silicate (PLS) nanocomposites often exhibit remarkable improvement in materials properties when compared with the virgin polymer or conventional micro and macro composites. These improvements can include high moduli and tear strength, improved heat resistance and electrical properties, decreased gas permeability, swelling to solvents and flammability.
Photocatalytic Degradation of Alizarin Cyanine Green G, Reactive Red 195 and Reactive Black 5 Using UV/TiO2 Process
Authors: Vyas Jaimin , Mishra Manish , Gandhi Vimal
Published: July 2013

The photocatalytic degradation (PCD) of three commercially textile dyes, namely Alizarin Cyanine Green G (ACG), Reactive Red 195 (RR195) and Reactive Black 5 (RB5) has been investigated using TiO2(Degussa P25) photocatalyst in aqueous solution under UV light. Experiments were conducted to optimize various parameters viz. amount of catalyst, initial concentration of dye and solution pH. Degradation of all the dyes was examined by using UV spectrophotometer. Photocatalytic degradation increased with increasing TiO2loading (in the range 0.51.5 g/L) and decreasing with increasing dye concentration (in the range 20-100 mg/L) and solution pH (in the range 4-10). Result demonstrated that the reactivity of the three dyes for TiO2catalyzed PCD was as follows: Reactive Red 195>Reactive Black 5>Alizarin cyanine Green G, respectively.
The Effect of Superheating and Cooling Rate on Primary Precipitation of Si in Hypereutectic Al-Si Alloys
Authors: Saleem Saud , Fredriksson Hasse
Published: July 2013

The effect of superheating and cooling rate on primary precipitation of Si was studied in hypereutectic Al-Si alloys. Alloys with compositions of 15, 18 and 20 wt% Si were solidified in unidirectional solidification equipment from different temperatures and drawing speeds. The fraction of primary silicon was measured over a certain distance of the sample in the steady state region. Results show a large variation in primary silicon fraction along the sample length and with varying cooling rate. The fraction of primary silicon and primary aluminium around silicon increases with increasing superheat. These fractions decrease with increasing cooling rate and the structure changes to a more refined dendritic-like primary silicon. Different morphologies of Si and their transformation during solidification can be seen over the sample length. An analysis of the quenched solidification front shows the possibility of strong convection ahead of the solidification front. The convection can be caused by density variation in the liquid due to the cluster structure of the melt which changes the microstructure.
Application Research on DC Casting Process by Annular Electromagnetic Stirring for a Modified 7075 Alloy
Authors: Xu Jun , Wang Hai Jun , Tang Meng Ou , Zhang Zhi Feng
Published: July 2013

The annular electromagnetic stirring (A-EMS) process, as an advanced melt treatment technology, is increasingly applied in metallurgy industry. DC casting by A-EMS was applied in this study to investigate the solidification behaviour of a modified 7075 alloy. The effects of DC casting without EMS, with normal electromagnetic stirring (N-EMS) and with annular electromagnetic stirring (A-EMS) on microstructure, composition segregation and mechanical properties of continuously cast billets were compared. Research results showed that the billets with higher performance, lower macro-segregation, more uniformly fine solidification structure were obtained in the case of A-EMS.
Comparison of Oxide Thickness of Aluminium and the Effects of Selected Alloying Additions
Authors: Hinton Elizabeth M. , Griffiths William D. , Green Nick R.
Published: July 2013

An experiment was undertaken to study the oxidation of liquid superpure aluminium (SP-Al) and alloys containing Mg, Si, Cu and Fe. The alloys were held at 750 °C, for a number of different holding times up to 7 hours. A comparison of the oxidation of SP-Al (superpure) held at 700 °C, 750 °C and 800 °C for 3 hours was also carried out. On observation of the samples using SEM and EDX the oxides of SP-Al and the Al-Mg alloy grew quickly (by 5.8 μm after 7 hours and 2 μm after 1 hour, respectively), in a manner reported in the literature. The other alloys had reduced rates of oxide growth, with thickness changes between 30 nm and 0.25 μm for Al-Si, Al-Cu and Al‑Fe alloys. Changes in holding temperature showed a thick oxide on samples held at 850 °C for 3 hours.
Influence of a Novel Master Alloy Addition on the Grain Refinement of Al-Si Cast Alloys
Authors: Bolzoni Leandro , Nowak Magdalena , Hari Babu N.
Published: July 2013

The grain refinement practice using Ti based chemical additions is well established for wrought Al alloys, especially in the last few decades. In the case of Al-Si casting alloys the practice of adding grain refiners and the impact on castability is not well established in industries. The main reason is the chemical instability of conventionally known Ti based grain refiner which reacts with silicon forming intermetallic phases. Recently, researchers at Brunel University have identified a novel chemical composition that can refine the grain structure of Al-Si alloys in an effective way. Over the last year, this novel grain refiner in the form of master alloy was developed and tested in various Al-Si cast alloys that are commonly used in industry. Significant grain refinement is obtained when the master alloy is added to the liquid metal prior to casting. Moreover, the grain size of the Al-Si cast alloys is observed to be less sensitive to cooling rate when the master alloy is added. In this work, the influence of addition of the master alloy on microstructural evolution of various Al-Si alloys cast under various cooling rates is presented.
Vacuum Induction Melting of TiNi Alloys Using BaZrO3 Crucibles
Authors: Zhang Zhao , Xing Fang Yuan , Zhu Ming , Zhu Kai Liang , Lu Xiong Gang , Wu Guang Xin , Li Chong He
Published: July 2013

In this paper, BaZrO3, which is successfully used to prepare the YBCO single crystal superconductor, is introduced into the melting of titanium alloys. The density of the home-made BaZrO3 crucible reaches 97% of theoretical density, and TiNi alloy is melted using this crucible by the vacuum induction method. It is found that the home-made BaZrO3 crucible possesses excellent thermal shock resistance. After melting, the surface of the ingot is smooth and it can be separated from the crucible easily, there is no reaction layer and elemental diffusion between the refractory and the melt is not observed, the oxygen content of the melt is about 600 ppm, and the increase of other impurity elements (i.e., Ba, Zr) is negligible. This implies that the BaZrO3 is a promising candidate for refractories for melting the TiNi alloy.
Formation of Bulk Nanostructured Al3Ni from Elemental Micropowders Using High-Pressure Torsion
Authors: Alhamidi Ali , Edalati Kaveh , Horita Zen Ji
Published: July 2013

The formation of bulk nanograined Al3Ni intermetallics from elemental micro-powder mixtures of Al-25 mol.% Ni are studied after processing by high-pressure torsion (HPT) for various turns at 473 K and at 573 K. It is found that nanograined Al3Ni intermetallics with high angles of misorientation are produced at temperatures well below the melting temperature. The fraction of Al3Ni intermetallics increases by increasing the shear strain and increasing the HPT processing temperature. During HPT, both Ni and Al atoms diffuse significantly in each other with a diffusion coefficient well comparable to the atomic interdiffusion in the Al3Ni intermetallic at its melting temperature.
Thermodynamics-Integrated Simulation of Precipitate Evolution in Al-Mg-Si-Alloys
Authors: Povoden-Karadeniz Erwin , Lang Peter , Öksüz Kerem I. , Jun Wu , Rafiezadeh Siamak , Falahati Ahmad , Kozeschnik Ernst
Published: July 2013

Metastable precipitates govern the mechanical properties of hardenable Al-alloys. A computational precipitation simulation approach is presented that is based on a combination of compiled and assessed thermodynamic and diffusion data with predictive physical models. Predictive precipitation kinetics simulation delivers approximations of thermodynamic properties that would otherwise require time-consuming computational techniques based on density functional theory. Coupling of thermodynamics with thermo-kinetic simulation of hardenable Al-alloys Al-Mg-Si 6016 is presented.
Fatigue Crack Growth in Cast and Wrought Aluminium Alloys
Authors: Gavras Anastasios , Spangenberger Anthony , Lados Diana A.
Published: July 2013

Fatigue crack growth (FCG) behaviour of cast aluminium alloys with different strengthening mechanisms (A535, 319, A356, A390) and wrought aluminium alloys (6061) was investigated in this study. Among the various parameters that can affect the propagation of fatigue cracks, the initial flaw size and microstructure were studied and correlated. Long and small FCG tests at low and high positive stress ratios were conducted on these materials in room temperature air. The mechanisms of FCG at the microstructural scale were identified and will be compared and discussed. In addition, two-parameter design diagrams were constructed to link loading conditions to microstructural response and fracture modes determined from fractographic observations. Finally, a new methodology and tools that can be used to bridge the differences between small and long fatigue cracks were developed and will be presented.
Relationship between Laser Parameters - Microstructural Modification - Mechanical Properties of Laser Surface Melted Magnesium Alloy AZ91D
Authors: Taltavull Catalina , Torres Belen , Lopez Antonio Julio , Rams Joaquin
Published: July 2013

Laser surface melting is a high-energy surface treatment that allows modification of the microstructure and surface properties of Mg alloys. In the present work, a high-power diode laser has been used to study the microstructural and mechanical modifications that occur when laser surface treatments are applied to the surface of the AZ91D Mg alloy. Laser-beam power in a range of 375-600 W and laser scanning speeds of 45-60-90 mms-1 has been used to develop a range of laser surface melting treatments. By controlling the laser parameters, two types of surface modifications can be obtained. Complete laser surface melting takes place at high laser input energies whilst at low laser input energies, selective laser surface melting occurs with modification of only one phase in the microstructure of the alloy; the other phase remained unaffected. In terms of mechanical properties, the microstructural modifications introduced by the laser surface treatment implied a hardness homogenization along the melted region.
Enhanced Mechanical Properties of AA5083 GTA Weldments with Current Pulsing and Addition of Scandium
Authors: Babu N. Kishore , Bhikanrao Patil Yogesh , Sivaprasad K.
Published: July 2013

AA5083 alloy is welded with gas tungsten arc welding using optimized welding parameters. Al-Si-Sc master alloy filler with varying contents of scandium is used for welding. Welding was carried out with and without AC-pulsed current techniques. A narrow heat affected zone with more refined grain structure is observed in the case of the pulsed current technique. Furthermore, it is observed that the columnar solidification structure in the fusion zone was suppressed and fine equiaxed grains were formed in the weld zone with increasing scandium content, which is attributed to the grain refinement effect of scandium with the generation of increased nucleating sites during weld solidification. This effect is reflected in mechanical properties also. An increased hardness of about 10 % results with pulsed current technique compared to about 20 % with an addition of 0.75 % scandium. However, in the case of tensile properties pulsing resulted in about 8 % increase in tensile strength and addition of 0.75 % scandium resulted in about 40 % increase in tensile strength. Both the pulsed current technique and the addition of scandium were observed to be better in increasing not only strength but also elongation due to the refined grain structure in the weld fusion zone.
High Strength Aluminium Sheet Metal Joining by Resistance Spot Welding
Authors: Gradinger Rudolf , Sotirov Nikolay , Rettenbacher Gottfried , Pangerl Christoph , Dörner Philipp , Minichshofer Stefan , Becirovic Almedin , Melzer Carsten , Uffelmann Dirk
Published: July 2013

Aluminium AA7075 is well known as extrusions, plate or sheet metal predominately in aerospace applications. The continuing efforts for reducing the weight but still maintaining the safety of vehicle structures are opening up the way for this alloy in automotive applications. Since this branch is very different to space as well as aircraft industries in manufacturing methods, costs and production numbers, the development of appropriate processes is necessary. After showing a high potential for deep drawing of AA7075 sheets under elevated temperatures, the joining technology options are now under investigation too. Since spot welding is very common in automotive body-in-white manufacturing, an innovative version of this process is evaluated for applicability for welding AA7075-T6 sheets to each other and to proven automotive aluminium alloys. The results of sample weldments, including mechanical static strength, micrographs, hardness, radiography and parameters for a stable process range, are presented.
Current Models of Dynamic Deformation and Fracture of Condensed Matter
Authors: Merzhievsky L.A.
Published: July 2013

The main types (groups) of models of deformation and the fracture, used for the solution of problems of dynamic and shock wave deformation of materials, are considered. All models are divided into three main groups: macroscopic (models of mechanics of continuous medium), microstructural (based on the description of evolutions of ensemble of defects ) and atomistic (are used in calculations by methods of molecular dynamics and quantum mechanics). The short characteristic of models of the listed groups is given. Some approaches to development of the most perspective multilevel models are described. The simple test for applicability of models for the description of shock and wave processes are offered. Approaches to the description of destruction of materials and used at this criterion are considered. The perspective directions of development of models of dynamic deformation and fracture are suggested.