bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of the Corona Discharge on ZnTe Film
Authors: Ri Na , Li Guo Rong
Published: August 2011

The effect of corona electric field on the surface of Pr-doped ZnTe thin film was studied. The device which can produce the high-voltage corona electric field is developed and used. The V-A characteristics of positive and negative corona discharge between the adjacent needle plates were measured. Whether positive or negative corona discharge, the corona discharge current of the plate is increased with the applied voltage increasing; the voltage range of negative corona discharge is wider than that of the positive corona discharge, meanwhile under the same applied voltage, the negative corona discharge current is bigger, not only its curve is smooth, but also its discharge is stable. The thermal effect of electric field is small. The electric field strength is 7.0 kV•cm-1. By atomic force microscope, it is found that the size of particles becomes large and uniform, and the surface becomes rough with electric field treatment. The measurement results reveal that the average radius of particles is 108.70nm before the effect and 227.27nm after the effect. By UV-Vis Spectrophotometer, it is found that a strong optical absorption peak appears at the region of 220 - 250nm with electric field treatment. This means that the stronger light absorption peak turn out a blue shift under the effect of electric field. The phenomenon of the blue shift proves that the high-voltage corona electric field has an impact on the band gap of the film. The voltage range of the negative corona discharge is wide and stable. The thermal effect produced by the high-voltage corona electric field on the sample is very small, so usually it can be ignored. The high-voltage corona electric field can change the surface morphology of some films, makes the current density of the sample location increase in a small cross section. The negative high-voltage corona discharge should well be used to research in biophysics such as the transgenic plants. High-voltage corona discharge mutagenesis has become a new physical mutation technique. Introduction
The Effects of Curvature Radius on Cutting Force and Stability during End Milling
Authors: Liu Wan Zhu , Liu Qiang , Gao Ge , Yan Xue
Published: August 2011

The influence of radius ratio of cutting point and cutter on cutting force and stability during end milling process is presented in this paper. To derive motion equations, a 2 DOF mechanical model of end milling considering both regenerative and self-excited effects was established. Different ratio values during three milling conditions were analyzed. Cutting forces as well as stability under different radius ratios by changing curvature radius and cutter radius were elaborated respectively. The results show that when other parameters are set fixed, cutter with relative large radius has smaller cutting force and larger stable range. Cutters with same radius will overlap on cutting force when radius ratio is large enough even under different milling conditions. The proposed analysis on cutting force and stability can be used to determine the optimal parameters, such as cutter radius and spindle speed etc. to improve the accuracy and productivity.
Wire Electrical Discharge Machining (Wire EDM) Cutting of Flexures for a Rotary Flexural Bearing Fabrication
Authors: Luo Hong Ping , Zhou Zhi Xiong , Zhang Yong Jun , Guo Zhong Ning
Published: August 2011

Wire electrical discharge machining (Wire EDM) cutting of flexures for a rotary flexural bearing fabrication is developed. The results of FEA calculation and theoretical analysis show that one of the main factors affecting flexures’ machining is the weak torsional stiffness of the bearing cage, thus excessive deflections due to machining stress, heat generation and spark-induced vibrations may occur. To minimize flexure deflection during the machining process, a specially designed fixture is utilized. Other technical measures, including residual stress relief before and after Wire EDM cutting, reasonable cutting sequence planning, multiple-cutting (i.e., rough cut followed by several trim cuts) etc., are also adopted for cutting. Dimensional accuracy of ±5µm was obtained over the 150µm thickness for the bearing flexures, a variation of less than 3µm was achieved for the flexures of opposing sides, and surface roughness of better than Ra 0.3μm was obtained for the flexures of the entire bearing cage. These results show the validity of measures aforementioned.
Monitoring of Tool Wear in Rotary Ultrasonic Machining of Advanced Ceramics
Authors: Liu Li Ping , Lin Bin , Fang Feng Zhou
Published: August 2011

Tool wear and failure monitoring has raised quite a lot of interests among researchers and has consequently been studied in a number of research projects by a number of research organisations. However, few researchers monitored tool wear in rotary ultrasonic machining (RUM) using various sensors. This paper, for the first time in literature, presents an experimental monitoring on tool wear in RUM of silicon carbide (SiC) using accelerometer, force and acoustic emission sensors. A digital microscope was used to observe the actual tool wear during the experiment. After describing the experimental procedures, it presents and discusses the results on tool wear and acceleration signal, force signal and acoustic signal in RUM of SiC
Development and Experimental Study of MWEDM Prototype
Authors: Huang Rui Ning , Lou Yun Jiang , Li Ze Xiang
Published: August 2011

A Micro Wire Electrical Discharge Machining (MWEDM) prototype is developed for fabricating micro complex parts. It mainly includes granite basement, micro energy pulse generator, precise servo mechanics, detection and servo control system, constant tension winding systems. Experiments are done on the prototype. Experimental results show that: the peak current and pulse duration have obvious influence on surface roughness and machining time, and they also have an optimum value for the highest cutting speed. The servo reference voltage also influences the surface roughness and machining time. Utilizing micro wire electrode with diameter in 30m, the MWEDM can machine micro slot with minimum size of 38m, which proves that the discharge gap width can be controlled not more than 4um, and so small discharge gap is beneficial for part’s machining accuracy. All kinds of complex micro part (such as micro gear, micro bearing bracket, micro shaped holes, etc.) can also be machined by this prototype.
Impact of Ni-2 Laser Cladding Coating on the Repeated Impact of the Dynamic Response
Authors: Shen Ling Lin , Shi Shi Hong , Fu Ge Yan , Liu Lei
Published: August 2011

Repeated impact tests on a 1Cr18Ni9Ti sample and a 1Cr18Ni9Ti sample with Ni-2 laser cladding coating are done and grade test data were collected intermittently. The results show that under the repeated impact loading which is far below the yield strength of material, there will be plastic deformation on both 1Cr18Ni9Ti sample and 1Cr18Ni9Ti sample with Ni-2 laser cladding coating, and the deformation of the former is more than the latter. For the 1Cr18Ni9Ti sample: from the perspective of impact frequency, the deformation rate of the gridding in every layer is largest in initial thousands of times, with the increasing number of impact, deformation rate decrease gradually, until zero; View from the layer in coordinates, more closer to the surface gridding layer, the deformation rate is larger, The average deformation rate of the gridding decreases continuously with the increasing layers deep. For the 1Cr18Ni9Ti sample with Ni-2 laser cladding coating: coating surface deformation is largest, change of gradient reduces gradually along the layer deep, that means repeated impact deformation has ‘skin effect’, the value is inversely proportional to the depth from the surface. The matrix deformation is similar with the coating, the value is inversely proportional to the distance from the faying surface.
Architectural Design of Bionic Structure and Biomimetic Materials
Authors: Huang Hai Jing , Wu Zu , Zhi Li Hui Zi
Published: August 2011

After a long evolution and natural selection, the creatures in the nature mostly have a graceful shape, reasonable structure and unique function. The architects have already got inspiration devised many beautiful and practical architecture from these creatures. This paper will compare some bionic architectural structure and material with the creatures in the nature to clarify a bionic structure, the principle and application of bionic material, so as to better understand the design connotation of biomimetic architecture for further development, and to provide the reference.
Service Rate Optimization of Manufacturing Cell Based on Cost Models
Authors: Zhang Yan Yan , Su Cheng , Shang Yong , Li Zhong Xue
Published: August 2011

Since most traditional manufacturing cell design methods and some involved algorithms developed in the past few years always investigate the selection and arrangement of equipment during the design process, this paper describes a new methodology focusing on optimizing the service rates of the manufacturing cell under developing. At first, the expected cost model based on queuing theory of each process in a manufacturing cell is developed and then the optimal service rates of the equipment that make the cost the least could be obtained. Next, the designer can choose the facilities according to these parameters to configure a new manufacturing cell whose total expected cost is optimal. Finally, a numerical example is used to illustrate the advantage and validity of the new design method.
Research on Jobshop Scheduling Problem with Energy Consumption
Authors: Wang Jia Hai , Gong Wen Tao
Published: August 2011

Discrete machine manufacture enterprises have to induce new low-carbon manufacturing model in order to solve a dilemma of mutual restraint between development and electric energy consumption. The paper presents an approach to solve JSP with the objective of minimizing the energy consumption by shortening the distance between electricity peak and valley according to theory of load shifting in electricity. The mathematical model is proposed for JSP with objective of minimizing the energy consumption and processing time of entire batch, then the idea of time division is introduced, and a solving method based on GA built-in eM-Plant is employed to verify the model and get satisfactory scheduling results.Discrete machine manufacture enterprises have to induce new low-carbon manufacturing model in order to solve a dilemma of mutual restraint between development and electric energy consumption. The paper presents an approach to solve JSP with the objective of minimizing the energy consumption by shortening the distance between electricity peak and valley according to theory of load shifting in electricity. The mathematical model is proposed for JSP with objective of minimizing the energy consumption and processing time of entire batch, then the idea of time division is introduced, and a solving method based on GA built-in eM-Plant is employed to verify the model and get satisfactory scheduling results.
An Improved Palmer-Based Heuristic for Two-Stage Flexible Flow Shop with Group Constraint
Authors: Li Zhan Tao , Chen Qing Xin , Mao Ning
Published: August 2011

Based on a background to the mould job shop, this paper considers a two-stage flexible flow shop scheduling problem subject to release dates, where the first stage is made up of unrelated machines and tasks have group constraint. The objective is to find a schedule that minimizes makespan in that flexible flow shop environment. For this problem, a mathematic model is formulated. Because this problem is NP-hard, an improved Palmer-based heuristic (denoted by MPL) is proposed. Based on MPL, a new heuristic (denoted by IMPL) is developed. In order to test the efficiency of the two heuristics, sets of examples are designed. Compared to the MPL, the performance of IMPL is more superior.
Nondestructive Testing of Wood-Plastics Structural Plates with Stiffener
Authors: Yu Gui Wen
Published: August 2011

In order to set up a new effective method for measuring mechanical properties of the wood-plastics structural plates with stiffener, three different nondestructive testing (NDT) methods were used on the specimens with stiffener, which were made of virgin high-density polyethylene (HDPE) with poplar fibers as filler. The values of dynamic Young’s modulus of the specimens were measured by a FFT system. And the values of static bending modulus of elasticity (MOE) were also determined by three point bending test according to ASTM D790-03. The paper analyzed the variability of the dynamic Young’s modulus of specimens with stiffener obtained with different NDT methods, and the correlativity was also estimated between the dynamic Young’s modulus and the static MOE of all specimens. The results suggested that the intensity of the wood-plastics structural plates could be enhanced by stiffener, and the NDT methods could be appropriate to estimate the dynamic Young’s modulus of the wood-plastics structural plates with stiffener.
Design and Analysis on Greedy Algorithm Based on Distribution Center Location
Authors: Liu Cheng
Published: August 2011

For the problem of distribution center location about 0-1 mixed integer programming, the necessary and sufficient conditions for the solvable model are given. A heuristic algorithm is designed with the idea of the greedy algorithm by further combined the model characteristics. It is proved that the algorithm could quickly converge to satisfactory solution, and the algorithm is bounded by polynomial time, and the complexity of the algorithm is given.
Developing a Selection Model for the Solar Power System
Authors: Chang Che Wei , Liu Chin Sung , Huang Ching Ya
Published: August 2011

Solar power is one of the most popular developing industries in the world. This study uses grey relational analysis to evaluate solar power products connected to the gen-connected system, hybrid-system and standalone system, with tracking system, tracking system with motors, and stationary type to select the most effective.
Synthesis and Luminescent Properties of New Oligofluorene Derivatives Containing Various Comonomers
Authors: Hu Xiao Dan , Wang Shao Hong , Hou Zhao Xia
Published: August 2011

Two kinds of oligofluorenes containing acetylene units are synthesized by Sonogashira coupling reaction. naphthalene and anthracene are co-polymerized with ethynylfluorene, respectively. The structure and properties are characterized using NMR, UV-vis spectroscopy, elemental analysis, DSC and photoluminescence. The oligomers are soluble in common organic solvents such as benzene and easily spin-coated onto glass substrates. The products yield strong emission differing from blue to green-yellow, and red-shift are suppressed with the growth in size of co-monomers.
Research on CAD Model Data Conversion for RP Technology
Authors: Cai Dong Gen , Zhou Tian Rui
Published: August 2011

The data processing and conversion plays an important role in RP processes in which the choice of data format determines data processing procedure and method. In this paper, the formats and features of commonly used interface standards such as STL, IGES and STEP are introduced, and the data conversion experiments of CAD models are carried out based on Pro/E system in which the conversion effects of different data formats are compared and analyzed, and the most reasonable data conversion format is proposed.
Research on the Variable Leads Transmission Mechanism Meshing Surfaces
Authors: Zhang Wei , Shi Xiang , Li Dong Bo
Published: August 2011

In this paper, the surface shapes of roller followers and spiral groove are researched. General surface equations of different types of roller follower are studied. According to the ordinary equation of spiral groove, the region shape between roller follower and spiral groove is discussed with the Hertz contact theory. By researching on the common mesh type, we can conclude that the gap shape function is elliptic equation.
The Application of DELMIA in ARJ21 Aircraft Central Wing Assembly Simulation
Authors: Liu Hong Jun , Tong Xiao Yan , Lv Sheng Li , Fan Qing Ming
Published: August 2011

This paper is to explain the application of DELMIA in 3D digital virtual assembly. It takes ARJ21 aircraft central wing assembly simulation process as an example. It introduces the related modules of DELMIA software and discusses the application of DELMIA in aircraft assembly simulation through the central wing assembly process simulation and human task simulation in the ARJ21 aircraft central wing assembly simulation.
Experimental Droplet Formation of Magnetostrictive Inkjet Head to the Change of Driving Waveform
Authors: Yoo Jae Hyun , Park Young Woo , Yoon Kyung Hyun , Yoo Eun Ju
Published: August 2011

This paper presents the experimental characterization of droplet formation in accordance with different types of driving waveform. The objective of the experiments is to generate sound droplets with a minimal volume depending on the types of driving waveform. For it, two types of driving waveform are used to investigate the droplet formation of the M-Jet: one is bipolar and another W-shaped. In the case of the bipolar waveform, ti lead to fluid flows from the liquid reservoir into the chamber in the M-Jet and th is time to impose a pulse under the constant magnetic field, resulting in the formation of the droplets. The droplet volume decreases as ti increases, and increases with further increase of ti. The threshold ti is equal to 500 s. The droplet volume decreases as th decreases, but the droplet formation was not successful at less than 550 s. In the case of the W-shaped waveform, maintains ti and th where is set from bipolar waveform, control the tr, where retracted MM keeps to control droplet volume. The tail becomes longer as tr increases. The droplet volume remains nearly constant as tr increases, but rapidly increases with further increase of tr. When the two driving waveform, the W-shaped driving waveform seems to be effective in reducing the droplet volume, and achieves the reduction of volume by 30 percent.
A Single Machine Scheduling Problem with Earliness and Tardiness Penalties Using Memetic Algorithm
Authors: Kaweegitbundit Parinya
Published: August 2011

This paper considers single machine scheduling problem. The objective is to determine sum of earliness and tardiness cost has been minimized. The memetic algorithm is developed to solve this problem. To evaluate performance of memetic algorithm, the solution of propose method is compare with the optimal solution. The results show that the average percentage deviation is less than 10. Here, the computational time required by the MA is significantly less than the time required by the optimal solution method. This result is more emphasized as the problem size is getting larger.
A Review on Development and Trend of Intelligent Maintenance System
Authors: Ao Yin Hui
Published: August 2011

Condition Based Maintenance (CBM) is becoming to be employed by many manufacturing factories. Performance prediction and multi objectives optimization are much needed in current CBM. The research of Intelligent Maintenance System grows rapidly. This paper summarized the key technologies of intelligent maintenance. It reviewed the recent research and developments in data acquisition, feature extraction, health evaluation and reliability prediction. The paper concludes with a brief discussion of possible future trend of intelligent maintenance.
Study on Measurement of Polymer Orientation Degree Base on SVM
Authors: Wang Yan , Lin Wei Guo , Xu Hong , Liu Tao
Published: August 2011

Aiming at the difficulty of measuring orientation degree of polymer material online, a soft-sensing approach based on ultrasonic velocity measurement is proposed．Firstly, the ultrasonic velocities of polymer samples are measured using a DSP-based ultrasonic velocity measurement circuit, with the ultrasonic sensor perpendicular to the extrusion direction of polymer material, the orientation degrees of samples are calibrated with infrared spectroscopy, the relationship between the ultrasonic velocities and the orientation degrees are then established based on SVM. With the measurement model and the ultrasonic velocity measured online, the orientation degree of polymer material can then be measured online. Test results in Lab shows that this approach can implement accurate measurement, and the relative error is about 5%.
Design and Implementation of Height Detection of the Cotton Top-Cutting
Authors: Xu Yan , Gou Xiao Peng , Zhou Jian Ping
Published: August 2011

This paper introduced an automatic height detection system of cotton top-cutting based on SCM80C51. The system finished primarily signal collection of cotton height, signal transmission, execution device control and feedback control between stroke displacement of hydraulic cylinder and the cotton height, implemented accurately height control to made the top cutter automatically adjust the top- cutting height to the change of the cotton height, completed precision operations of agricultural.
Design of Stable Image Platform on Airborne Camera
Authors: Qian Yi Xian , Yang Li Bao , Hu Fang Rong , Hong Xue Ting
Published: August 2011

Modulation transfer function resulting from random vibration was analyzed. To conclude that the effect of angular displacement was the major factor. Allowable MTF degradation was represented, and convert allowable MTF degradation into stable system design parameters, which can guide perfect design for stabilization system. Based on the spatial mechanism and translational principle of parallelogram, an irrotational displacement isolator was developed. It can meet the requirements of irrotational displacement and damp. An instance was given; and 34dB reduction was achieved at frequency of 100HZ. With the help of MSC.ADAMS simulation software, simulated curve proves correct for isolator, and the irrotational displacement mechanism was tested by optical method, coupled angle is less than 8″, it can satisfy the demand of aerial imaging.
A Method of Speech Segregation in Noisy Environment
Authors: Li Cong Qing , Sun Li Ying , Li Jian Jun
Published: August 2011

On the basis of zero-crossings detection, a new method of speech segregation is proposed using these clues of Interaural time difference(ITD), zero-crossings peak amplitude(ZCPA) and zero-crossings power. The estimation of ITD is utilizing the statistical properties of zero-crossings detected from binaural filter bank outputs in order to get more reliable ITD estimation in noisy environment. Signal phase ambiguity in the high frequencies is solved by correcting the signals in the high frequency channels by means of the ITD values calculated by ZCPA algorithm in the low channels. Spline interpolation is used for sound segregation in order to make sound signal segregated correspond to the original sound signals as much as possible. The test for sound segregation in various mixture sources is made. The results show that the method can make can segregate various mixed sound sources effectively. The advantages of the proposed method are the robustness to noise, the less computational complexity and no need to train the masks for sound segregation.
Modeling and Analysis of End of Life Vehicles Recovery: an Enhanced IDEF0 Methodology (Part I)
Authors: Wang Yu , Chen Ming , Gao Jun Qing , Chen En
Published: August 2011

During the entire life cycle of a vehicle, from design, manufacture, usage to final recovery, there exist very complex materials, energy and information flow as well as the interactions among different stages. To better understand this closed loop, it’s important and significant to model the whole loop from a system engineering point of view. This work proposed a unified modeling method based on enhanced IDEF0. By taking materials flow, information flow, energy flow as well as the interactions among processes into account, a holistic hierarchical model for the entire life cycle of vehicles was established in this work, which helps to provide a novel way of understanding the recovery infrastructure, identifying the key issues to be tackled, and further finding the opportunities to improve it.
Modeling and Analysis of End of Life Vehicles Recovery: An Enhanced IDEF0 Methodology (Part II)
Authors: Wang Yu , Chen Ming , Gao Jun Qing , Chen En
Published: August 2011

The process of end-of-life vehicles (ELVs) recovery usually includes pre-treatment, dismantling, shredding, non-ferrous sorting and finally energy recovery or land-filling. Using enhanced IDEF0 method, various models corresponding to different stages of a vehicle’s life cycle were established in this work together with previous work. Based on these models some key issues are identified to help make a better strategy for ELVs recovery so as to meet the increasing rigors requirements by legislatives such as EU directives.
Investigation into Tribological Properties of TD-Treated D2 Steel for Applications in Dry Machining of Aluminum Alloy
Authors: Wang Lin Lin , Nie Xueyuan
Published: August 2011

This research is to investigate tribological properties of thermal diffusion (TD) treated D2 steels against aluminum (Al 6061) counterface material for its potential applications in dry machining/forming of aluminum composite materials. A hard vanadium carbide (VC) layer was formed on the tool steels by the TD process. Original D2, thermal treatment hardened D2 and TiN coating on hardened D2 were used as references. Pin-on-disc tribo-tests were performed on those samples against Al pins under a dry sliding condition. Wyko profilemetry analysis showed that Al pin material transferred to the D2, hardened D2 and TiN coating surface and caused adhesive wear, which may negatively influence product quality in machining/forming applications. The TD-VC coating on D2 steel has a good adhesive wear resistance and anti-sticking of aluminum performance, which is a promising material used for dry machining/forming of aluminum.
Studying on Rare Earth Aluminizing Process of GH4169 Superalloy
Authors: Luo Jun Ming , Xu Ji Lin , Deng Li Ping
Published: August 2011

The aluminizing process by solid powder on the surface of GH4169 superalloy with different Y2O3 content and different aluminizing temperature was investigated in this paper. The results show that the crystalline phase of aluminized coating is composed of AlNi, FeNi and AlNi3, and the phase of AlNi reaches 78.1%, which indicates that aluminium atom has infiltrated into the alloy surface. Y2O3 can greatly improve compactness of the aluminized coating, increase thickness, surface micro-hardness and high temperature oxidation resistance of the aluminized coating. The thickness of the coating increases with the increase of temperature, but the microstructure of the aluminized samples cannot obviously divided into aluminized layer, transition layer and matrix when the aluminizing temperature is too high (980°C) or too low (920°C), and even the aluminized coating is porous and coarse at 980°C. The high temperature oxidation resistance of all the aluminized samples is improved compared to without aluminized samples. According to the microstructure, thickness, surface micro-hardness and high temperature oxidation resistance of aluminized coating, the optimal aluminizing process is 950°C×7h with 4%Y2O3.
Formation Mechanism of Nanostructure of HVOF Sprayed Nanostructured WC-17Co Coating
Authors: Gou Guo Qing , Huang Nan , Chen Hui , Li Da , Liu Yan , Ji Hua , Zhu Yong Hui , Wang Gui Guo , Yu Jin Peng
Published: August 2011

Nanostructured WC-17Co coating was prepared by means of High Velocity Oxygen Flame (HVOF) technique. Characteristic of nano-structure of the coating was analyzed. The coating seems to be of lamination structure formed by fully or partially melted powder. It shows that the coating consists of melted and recrystallized zone, semi-molten zone and un-melted zone. Amorphous phase and nanocrystalline phase co-existed in the coating is due to the rapid heating and cooling during spraying. The nanostructured coating possesses excellent mechanical properties, which are closely related to the unique nanostructures existed in the coating.
The Research on Cylindrical Ultrasonic Rolling Machining Used for Strengthening Metal Surface
Authors: Chen Wen Rui , Ma Yong , Lou Zhi Feng
Published: August 2011

Material mechanics and dynamic properties affect the service life of parts, and also the normal operation of machines. In order to reduce the processing time and improve the quality of machining, a cylindrical roller was used in the research. Cylindrical ultrasonic rolling machining (CURM) is an efficient way to enhance the service properties and surface characteristics of components. CURM was designed and later tested on the 45# steel surface. The result showed that the plastic deformation of surface layer was symmetrical and the surface grain was reduced in size by approximately 4.2%. The result of the experiment showed that CURM was effective in enhancing the productivity as well as enlarging the yield strength and hardness of components.
Microstructure and Properties of In Situ Synthesized Composite Coating by Tungsten Inert Gas Cladding
Authors: Zhao Li Ping , Liu Zong De , Li Bin
Published: August 2011

Ceramic particulate-reinforced Ni-based composite coatings are commonly used in the industry for protection against wear. With an aim to investigate the properties of this coating, ceramic coating reinforced by in-situ synthesized (Ti,Cr,Nb,Mo)xCy particles was prepared on AISI 1045 steel substrate by tungsten insert gas cladding. The microstructure and microhardness of the coatings were analyzed by scanning electron microscopy (SEM) and microhardness tester. The results showed that excellent bonding between the coating and the AISI 1045 steel substrate was uniform, continuous and almost defect-free. The maximum hardness value achieved 1013HV, which is about 5 times compared to that of the AISI 1045 steel substrate.
Angular Distortion Analysis on Multipassed Welding of Combined Joint Types Using Thermo-Elastic-Plastic FEM
Authors: Lidam Robert Ngendang A. , Manurung Yupiter H.P. , Ridhwan M. , Ridzwan M.A.R. , Shahar S. M. , Yusof Z. M. , Sunhaji K.A. , Ghalib T. , Haruman E. , Chan Y. C.
Published: August 2011

A 2D and 3D thermo-elastic-plastic (TEP) FE Analysis has been developed to simulate the angular distortion induced by Gas Metal Arc Welding (GMAW) process on combination of butt and T-joint with thickness of 9 mm. The material used in this study was low alloy Manganese Carbon steel S355J2G3. In this research, SYSWELD 2010 with its computation management tool known as Multipassed Welding Advisor (MPA) was used to analyze the distortion behaviour of combined joint types. To model the heat source of GMAW, Goldak’s double ellipsoid representation which is available within this FEA code was selected. The final objective of this research is hence aimed to be base line study to provide preliminary information in preparing the tools or equipments for experimental investigation.
Research on Radio Frequency Wireless Communication Technology
Authors: Shang Xiao Feng , Wang Zhi Jian , Fan Chao Gang
Published: August 2011

On many occasions, the wired communications technologies can not meet the actual needs, such as in the operating in the wild or harsh environment. If using communication module built by radio frequency communication chip to achieve the data transmission of two regions of space, take MCU as a control component to achieve the freely data communication docking. This will be a good way to solve the wireless communications problems.
Computer Simulation of Heat Treatment Process for Support Plate of Nuclear Reactor
Authors: Liu Xing , Mukai Ryuji , Deng Xiao Hu , Ju Dong Ying
Published: August 2011

This paper focuses on the thermal stress and deformation analysis of the support plate of a nuclear reactor during the quenching process. A 3D finite element model of the support plate is incorporated into nonlinear coupling analysis that considers temperature, stress, and deformation. To verify the effect of cooling rate on the thermal stress and deformation of the model, we applied the heat transfer coefficients of water and heat treatment oil, depending on temperature variations, into heat conduction analysis. This analytical method enables the determination of the maximum deformation and residual stresses, so that the strength of the support plate can be identified.
Quality Diagnosis and Error Compensation Based on Integrated SPC/EPC in MMPs
Authors: Feng Jia , Jiang Ping Yu
Published: August 2011

In the multistage machining processes (MMPs), SPC is widely utilized to control the quality of machining processes and diagnose the processing error. But there is a defect, that it can not compensate the error when the machining process is abnormal. For this issue, a new method of quality diagnosis and error compensation is proposed based on EPC (engineering process control). A new framework for processes quality diagnosis and error compensation about the description of machining processes and controlling mechanism of machining process quality is proposed first. And the mapping model of machining error propagation is introduced to explore the model of the error compensation decision. From theoretical level, modeling level and solution level, the mapping model from the decision model based on EPC to SPC is studied, in which the key technologies are the machining error propagation model and the error compensation model. Therefore, the machining error propagation network is utilized to build the error propagation model, and an adaptive control method based on the stability theory is introduced to make error coordination optimization.
Study on Metal Flowing Law for Isothermal Extrusion Deformation of AZ31 Magnesium Alloy
Authors: Li Xu Bin , Zhang Zhi Min
Published: August 2011

In this paper, rigid plastic finite element method simulation of AZ31 wrought magnesium alloy radiator isothermal extrusion is studied according to the stress - strain data of magnesium alloy obtained from isothermal compression experiments and the mathematical model of warm forming by the regression. And the paper focuses on the AZ31 magnesium alloy during isothermal extrusion, the deformation force and metal flowing law. The simulated stress field, strain field, velocity field, load changes and so on from simulation can predict the defect in deformation, and offer the reliable reference basis for such parts processing in isothermal extrusion.
Process Research on Cold Rolling of Gulley Ball Bearing Inner Ring
Authors: Qi Liang Tao , Sun Bao Shou , Shu Xue Dao
Published: August 2011

3D model of 6006 gulley ball bearing inner ring is established in this paper. Based on the study of finite element numerical simulation on the cold rolling process of inner ring by Deform-3D software, the paper shows the influence of the feed rate of idle roller, rotational rate of driving roller as well as wide-diameter ratio on the rules of rolling forming of bearing inner ring. Through the research of numerical simulation, it is discovered that feed rate of idle roller and wide diameter ratio have a greater impact on the ring end surface quality larger than rotational rate of driving roller does. Thus, process parameters should be chosen reasonably according to mold parameters and material parameters, which will help improve the stability of the cold rolling process and the rolling production efficiency.
Influence of Initial Microstructure on Rheology of Al-Zn-Mg-Cu Alloy during Thermal Compression
Authors: Xu Lei , Dai Guang Ze , Huang Xing Min , Zhao Jun Wen , Han Jing
Published: August 2011

The rheological behavior of two kinds Al-Zn-Mg-Cu aluminum alloy with different extrusion ratio was studied by thermal compression in 300°C~450°C and in strain rate range of 0.01 s-1~10s-1 on Gleeble1500D simulator. The results show that: (1)the flow stress increases with deSuperscript textcreasing deformation temperature and increasing strain rate, and the initial microstructure influence the rheological behavior, the flow stress with fine grain is higher than that with coarse one except in strain rate 0.01s-1 and 0.1s-1 in 450°C owing to deformation easily with more grain boundary sliding in high temperature and low strain rate.(2)The flow stress of Al-Zn-Mg-Cu aluminum alloy during hot compression can be expressed as hyperbolic sine constitutive equation with Arrhenius parameter, the apparent steady state activation energy for hot compression with coarse grain is of 181.51kJ/mol, while that with fine grain is of 203.02kJ/mol.(3) The apparent steady state activation energy decreases with increasing temperature and strain rate, and the value of fine initial microstructure is higher than the low extrusion ratio rod commonly.
Influence of Processing Parameters of Warm Compaction on Green Density of Molybdenum Powder and Compact Defect Analysis
Authors: Li Jian , Yang Bin Ting
Published: August 2011

Utilization of MSC.Marc FEM software, the typical warm compaction process of molybdeum powder was simulated. Influence of processing parameters of warm compaction on green density of molybdenum powder were studied. Furthermore, the commonly defect existing in green body were analyzed. The results show that compaction pressure is an important factor on green density. At the beginning of warm compaction, average relative density rises linearly along with the increasing pressure. The green density increases with the suppression speed increasing, when velocity value reaches 7mm/s the density will not increase anymore. After the value of friction coefficient is greater than 0.1,green density decreases with the friction coefficient increasing. Influence of temperature on compaction is improvement of the lubrication condition, and reduces the friction coefficient. The appearance of axial tensile stress is the important factor which causes delamination and cracks. Internal friction and lubrication condition of powder mixed system is the important reason results in defect.
Prediction of Fracture Force of Weld Line Based on Artificial Neural Networks
Authors: Zhu Peng Fei , Sun Xiao Fang , Lu Ying Jun , Pan Hai Tian
Published: August 2011

A feed-forward three-layer neural network was proposed to predict the fracture force of injection-molded parts’ weld line. Firstly, the most significant process parameters which affect the fracture force of weld line were analyzed. Secondly, melt temperature, injection pressure, holding pressure and holding time were chosen as import variables and the fracture force of weld line was chosen as output variable to construct artificial neural networks. Furthermore, the performance of ANN was evaluated and tested by its application to verification tests with process parameters randomly selected which all of them were not used in the network training. Results showed that the ANN predictions yield mean absolute percentage error (MAPE) in the range of 0.86％,and maximum relative error (MRE) in the range of 1.84％ for the test data set, and which can comparatively accurately reflect the influence relation of the injection process parameters on part’s quality index under the circumstance of data deficiencies.
ANSYS-Based Finite Element Analysis on Automotive Panel Drawing Die
Authors: Wang Jian Ping , Liu Cheng Long , Lu Peng , Ma Fu Gui
Published: August 2011

Taking a company’s automotive panel drawing die as an example, this paper numerically simulates the process of drawing forming based on finite element analysis (FEA) software ANSYS, the design rationality of die structure is analyzed combining distribution characteristics of stress and strain, the paper also proposes feasible improvment measures according simulation analysis to optimize the structure of drawing die. The study result shows that analysis results based on ANSYS can forecast defect and failure regions in the forming process of automotive panel drawing die, optimize the design of drawing die, prolong the die life effectively, and reduce production cost.
Research on the Blank Design Method of Closed Rolling the High-Neck Flange
Authors: Xiao Min , Shu Xue Dao
Published: August 2011

Blank shape design is the prerequisite and foundation of optimization for the closed forming the high-neck flange. This paper obtained the design formulas of blank size with analyzing the mathematical model of flank blank based on the principle of volume invariably during the rolling process.The blank of a special flange was designed by this method which was validated by the numerical simulation under the DEFORM software. The results indicate that the product is qualified with the blank shape based on this method. These research conclusions can provide scientific basis for forming the high-neck flange with rolling method.
Simulation of Temperature Field during the Laser Sintering Process of Nano-Hydroxyapatite Powder
Authors: Shuai Cijun , Feng Pei , Gao Chengde , Zhou Ying , Peng Shu Ping
Published: August 2011

A three-dimensional finite element model has been created to study the change rules of temperature field during the laser sintering process of nano-hydroxyapatite powder. The numerical simulation of temperature distribution has been achieved based on the equivalence between the sintering time and the sintering speed. The simulation results show that the temperature declines gradually along the radial direction of the laser spot. At the same time, there was the largest temperature gradient at the edge of the laser spot. The temperature of sintering layer rises with the increase of laser power linearly when the other process parameters are the same. The maximum sintering temperature is 1320°C with laser power of 8.75W, laser spot diameter of 4mm, sintering time of 5s and layer thickness of 0.2mm. The test results verify that nano-hydroxyapatite powder could be sintered under this process condition. It shows that the finite element model can be used to simulate the temperature field during the laser sintering process.
An Optimum-Curved Die-Profile for Investment Casting of Turbo Blades
Authors: Dong Yi Wei , Zhang Ding Hua , Bu Kun , Dou Yang Qing
Published: August 2011

In order to avoid tremendous modifications of the die cavity for investment casting of turbo blades, this paper proposed an inverse iterative compensation method that adjusts certain geometric parameters to establish the die-profile. The parameterized modeling is achieved by identifying geometric parameters describing the mean camber line; the optimum-curve die-profile can be obtained based on the inverse iteration algorithm. As a result, the dimension precision of turbo blades can be guaranteed. The applicability of this method is validated using numerical simulation data.
The Research of Shock Wave Attenuation Test of UHMWPE-PUF Composite by PVDF Piezoelectric Sensor
Authors: Cai Jun Feng , Yi Jian Zheng , Li Tian Peng
Published: August 2011

In the paper, The PVDF piezoelectric sensor was customized and the structure and test circuit of PVDF piezoelectric sensor is introduced. The polyurethane(PUF) reinforced by ultra high molecular weigh polyethylene (UHMWPE) material(UHMWPE-PUF composites) was synthesized. The pressure in UHMWPE-PUF composites under explosion load was measured and shock wave attenuation waveform is gained and the data is analyzed. The studies showed that PVDF piezoelectric firm sensor is suitable to shock wave measurement in material and UHMWPE- PUF composites can improve maximally shock wave attenuation properties of the material and have good applied outlook in the realm of anti-explosion.
Microstructure and Property of Cold Sprayed Copper Coating
Authors: Liu Yu Liang , Bao Zebin , Xiong Tian Ying
Published: August 2011

Cold spray is a new surface engineering technology. In this paper, pure copper particles were sprayed on the Al substrate by this method and the copper coating was deposited sucessfully on the surface of the substrate. The microstructure of the coating and the interface between the coating and the substrate were observed by optical and scanning electron microscopes, and the phase was identified by XRD for the pure copper particles and the coating. The microhardness of the coating is measured. The results show that mechanical bonding is the main mechanism for the interface between the coating and the substrate, and there is a few metallurgical bonding for the interface; the coating is dense and its porosity is less than 0.4%; XRD results indicate that there is no oxidation occurred during the spray process. The microhardness of the coating is about 160Hv, which is higher than that of the as-casted copper.
Indirect Hot Stamping of Boron Steel 22MnB5 for an Upper B-Pillar
Authors: Min Jun Ying , Lin Jian Ping , Xin Li Jiu , Li Jia Yue
Published: August 2011

During the indirect hot stamping process of boron steel, the pre-deformed component undergoes air cooling, one-side-contact cooling and both-side-contact cooling phases successively. The effects of pre-deformation and cooling rate on the phase transformation should be understood before conducting indirect hot stamping experiments of vehicle components. Uniaxial tensile tests of boron steel at RT were carried out to obtain specimens with different pre-strain levels. Then they were heated to 900°C according to the indirect hot stamping process and quenching tests were performed on them at different cooling rates. Metallographic observations were performed on the quenched specimens and their hardness was measured. The results show that the pre-strain at RT has little influence on the phase transformation of boron steel. This is due to the dislocation structure introduced by deformation at RT recovered during the heating process and it is good for the indirect hot stamping. Upper B-pillar parts were first cold pre-formed, and then were heated and hot stamped. The microstructure and hardness results at different locations on the indirect hot stamped components are demonstrated qualified.
The Innovation and Application of the Piercing Process inside of Parts
Authors: Zhang Yu Ping , Wei Guang Zhen , Xu Lai Min
Published: August 2011

This article analyses the characters of piercing process inside of automobile cover parts. It introduces the designing structure, its advantages and disadvantages in piercing process inside of automobile cover parts by a traditional process and by a new process. The traditional process is using cams across a bridge, but the new process is a creative way that is using PAD built-in standard cams. By comparing two processes, the new creative process is convenient for operations and ensures the combining moulds in one time. This mould has a tight structure and the dimensions are reduced significantly, which is benefit for shortening the moulds’ manufacturing cycle. The new process has some guiding significance for the parts by similar piecing inside process. It has been spread and applied in a cooperative company.
Velocity and Current Density Evaluation of Combined Plasma Arc for High Temperature Materials Processing by Computational Simulation
Authors: Dong Xiao Juan , Meng Jian Bing , Yin Zhan Min , Ma Chang Ning
Published: August 2011

A mathematical model was established to describe the electromagnetic, heat flow and fluid flow phenomena within a combined plasma arc. In the development of the model allowance was made for the conservation of mass, momentum, energy and the Maxwell equations. With the ANSYS finite analysis software, specific calculations were presented for a pure argon system, operating in a laminar mode. The distributions of the current density and velocity of combined plasma arc were gotten. In addition, the influences of process parameters, including arc current, argon gas flow rate and the distance from the nozzle outlet to the anode workpiece, on the velocity along the axial direction and current density distribution along radial direction were evaluated, respectively. The results shows that the velocity and current density of combined plasma arc are much dependent on the working current, while are less sensitive to the argon flow rate and the distance from the nozzle outlet to the workpiece anode.