bluuebunny/crossref_metadata_2025 huggingface dataset:
Finite Volume Simulation in Porthole Dies Extrusion of Aluminum Profiles
Authors: Cheng Lei , Xie Shui Sheng , He You Feng , Huang Guo Jie , Fu Yao
Published: July 2011

FEM simulation of aluminum profiles in porthole die extrusion process using Lagrange mesh description will inevitably bring mesh self-contact, severe grid distortion and frequent remeshing, which will result in the loss of computational accuracy and excessive calculation time. In order to solve the above mentioned problems, numerical simulation of aluminum profiles with large and complicated cross-section in extrusion process was achieved using finite volume method based on Euler mesh description. The metal flow behavior and welding course was investigated in detail, which can provide the theoretical guide for porthole die design and optimization. In addition, extrusion experiment was carried out by numerical simulation results. The experimental extrudate was in good agreement with the simulation results, which laid a good solid foundation for non-steady state extrusion process analysis of large scale and complicated cross-section profiles.
Uniformity Assessment of Digital Prints based on NPS and CSF
Authors: Kong Ling Jun , Jiang Zhong Ming , Gao Xue Ling
Published: July 2011

The standard for digital print quality and its measurement technology is now under consideration, and uniformity evaluation should be an important and essential quality factor. The paper provides a practical quantitative measurement method for traditional visual assessment on uniformity, and proposes a simple and effective IUI index to evaluate the uniformity of digital prints through NPS curve of the printed flat areas and CSF of HVS. The validity of the IUI is demonstrated through its applications in the uniformity assessment of the digital prints.
Decentralized IMC-PID Controler Design for Multivariable System
Authors: Jin Qi Bing , Jia Shao Qiong
Published: July 2011

For a class of multivariable second-stage time delay system, this paper study the decentralized controller designing method based on RNGA matching method, then design the IMC-PID controller for the paired main elements. Simulation results show that the decentralized control method can easily control the original system, using the IMC-PID controller, the control effect obtained enhancing
J-Automatic Welding Robot Software Design
Authors: Song Hai Feng , Lv Xiao Qing , Hu Sheng Sun
Published: July 2011

In this paper, according to nuclear reactor pressure vessel for the J-groove type, independent research and development of a special groove in the J-automatic control system program. This paper introduces a PC-based industrial computer as the host operating system and the functional modules are described respectively, by comparison of a variety of robot programming languages​​, ultimately to achieve the goal of the program using the Visual C++ MFC platform. The system has a friendly interface, which can be easily set to display, on-line adjustment and automatic welding for the preservation, through simulation experiment with industrial PC connection to verify that the entire system software design is reasonable, functional and meet the actual needs of production.
Researches on the Ring Stiffness Condition in Cold Ring Rolling
Authors: Pan Li Bo , Hua Lin , Qian Dong Sheng
Published: July 2011

Cold ring rolling is a kind of advanced manufacturing technology. During rolling process the ring may be collapsed or deformed unexpectedly under the pressure of guide roll because the stiffness condition is not met. The force of guide roll to ring was obtained by analyzing the forces to ring. The stiffness condition expressions of ring during rolling were shown after constructing the mechanical model. According to the expressions, the effects of several parameters on the stiffness condition were discussed and analyzed in detail, such as position angle of guide roll, friction coefficient and feed rate, etc, which revealed essential reasons of some cases occurring in cold ring rolling. Then the ring blank dimension was deduced based on the ring stiffness condition. The dimensions of ring blank should meet a relationship to ensure the ring stiffness condition to be satisfied during rolling, which can conduct the practical manufacturing effectively. Finally the analysis and effect laws were proved by finite element simulation experiments. The researches could be helpful to control parameter in cold ring rolling effectively for high quality products.
Effect of Different Particles Distribution on Microstructure and Corrosion Resistance of Nickel-Base Laser Cladding Coatings
Authors: Cao Yang Xiao Lu , Ma Ming Xing , Wu Qi Wen , Ye Xiao Yang , Liu Wen Jin , Zhang Hong Jun
Published: July 2011

Nickel-base composite coating reinforced by in situ synthesized multiple carbide particles were fabricated on AISI 1045 steel surface by pre-placed laser cladding. Nowadays most researches focus on the wear resistance. This study mainly focuses on the corrosion resistance property. Investigate the effect of different particle distribution on corrosion resistance of the cladding layers by controlling the amount of Zr, Ti and WC. The microstructure and electrochemical property are analyzed by scanning electron microscope (SEM) and electrochemical test equipment. The maximal particle distribution density and particle area ratio appear when Zr:Ti:WC=1:2:2. The polarization curves show that in 0.05mol/L HCl electrolyte the coatings’ corrosion resistance have positive correlation with particles distribution density and particles area ratio, and all the coatings are significantly better than 314L stainless steel in corrosion resistance.
Proposal for Machining Optical Free Form Surfaces Using Atmospheric Pressure Plasma Jet
Authors: Zhang Yan Fu , Wang Bo , Dong Shen
Published: July 2011

Optics with free form surface can be achieve special imaging effects and reduce component amounts in optical systems. However, it is difficulty to fabricate high accuracy, damage-free optical surface with free form surfaces by conventional method. Atmospheric plasma machining is a non-contact chemical processing method which can fabricate optics without damaged layer. Numerical controlled atmospheric pressure plasma machining (NC-APPM) method is proposed to machine optical free form surfaces. A new atmospheric pressure plasma jet generator was designed to get Gaussian rotational symmetry removal spot and the spot maximum diameter is 1.5mm. Base on dwelling time algorithm, a sinusoidal wave structure, the pitch 2mm and the amplitude 500 nm, is fabricated on a pre-polished flat silica quartz surface using three-axis numerically controlled machine made by ourselves. The result shows that the amplitude error is 59 nm compare to the expectation value surfaces using numerical controlled atmospheric plasma machining method.
Synchronous Control of Multi-Integrated System of Electro-Hydraulic with Mechanic Based on Virtual Axis Model
Authors: Yang Ji Dong , Wu Jian Qu , Deng Yong Quan
Published: July 2011

The article gives a solution to the precise synchronous control of multi-hydraulic cylinders which exist in the large-sized pressure and flattening machine by the virtual axis method. To fulfill the job, the scheme introduces the acceleration feedback to the virtual control model to make the model practical. According to the Newton’s mechanical law and fluid mechanic, the article set up the model mentioned above. The control system presented is investigated through simulation of Matlab under step disturbance and productive practice which successfully demonstrate the effectiveness of the proposed control model.
Investigation of Dry Cutting and Applications of Cutting Fluid in Ball-End Milling Process
Authors: Tangjitsitcharoen Somkiat , Rungruang Channarong
Published: July 2011

In order to realize the environmental hazard, this paper presents the investigation of the machinability of ball-end milling process with the dry cutting, the wet cutting, and the mist cutting for aluminum. The relations of the surface roughness, the cutting force, and the cutting parameters are examined based on the experimental results by using the Response Surface Analysis with the Box-Behnken design. The in-process cutting force is monitored to analyze the relations of the surface roughness and the cutting parameters. The proper cutting condition can be determined easily referring to the minimum use of cutting fluid, and the minimum surface roughness and cutting force of the surface plot. The effectiveness of the obtained surface roughness and cutting force models have been proved by utilizing the analysis of variance at 95% confident level.
In-Process Monitoring and Estimation of Tool Wear on CNC Turning by Applying Multi-Sensor with Back Propagation Technique
Authors: Tangjitsitcharoen Somkiat , Rungruang Channarong
Published: July 2011

The aim of this research is to propose and develop the in-process monitoring system of the tool wear for the carbon steel (S45C) in CNC turning process by utilizing the multi-sensor which are the force sensor, the sound sensor, the accelerometer sensor and the acoustic emission sensor. The progress of the tool wear results in the larger cutting force, the higher amplitude of the acceleration signal, and the higher power spectrum densities of sound and acoustic emission signals. Hence, their signals have been integrated via the neural network with the back propagation technique to monitor the tool wear. The experimentally obtained results showed that the in-process monitoring system proposed and developed in this research can be effectively used to estimate the tool wear level with the higher accuracy and reliability.
Modeling and Optimization of Mould Non-Sinusoidal Oscillation Process
Authors: Wang Hong Ming , Yang Bo Feng , Song Bang Min , Zhang Ting Wang , Yan Yong Qi
Published: July 2011

A model on non-sinusoidal oscillation of continuous casting mould was established to study the pressure in flux channel. The effects of oscillation parameters on the pressure in flux channel were researched. The non-sinusoidal oscillation parameters were optimized. When the casting speed is 1.8 m·min-1, the optimized oscillation parameters are: non-sinusoidal factor (α) is 0.198, oscillation amplitude (s) is ±4mm and oscillation frequency (f) is 165min-1. When the casting speed is 2.0 m·min-1, the optimized oscillation parameters are: α is 0.186, s is ±4.5mm and f is 155min-1. These optimized oscillation parameters are proved applicable in practice.
Cutting Performance of Cemented Carbide-Based Self-Lubricating Tool Embedded with CaF2 Solid Lubricants
Authors: Song Wen Long , Zhang Li Yin , Xu Chang Zhong , Li Xuan Qiu , Yan Jian Feng , Deng Jian Xin , Zhang Liang
Published: July 2011

Four micro-holes were made using micro-EDM on the rake face of the cemented carbide (WC/TiC/Co) tools. CaF2solid lubricants were embedded into the microholes to form self-lubricating tool (SLT-1). Dry machining tests on hardened steel were carried out with the SLT-1 self-lubricating tool and conventional tool (SLT-2). The cutting forces, tool wear and friction coefficient were measured and compared. It was shown that the cutting performance of SLT-1 self-lubricating tool was greatly improved compared with that of the SLT-2 conventional tool. Through the analysis of cutting force theory and test results, the mechanism of cutting performance improvement was considered to be the formation of a self-lubricating film on the rake face which decreases the shear stress and the reduction of contact length between chip and tool.
Simulation of Miniature Vapor Compression Heat Pump System
Authors: Zhong Xiao Hui , Gou Yu Jun , Zhou Shu Guang , Wen Zhi Mei
Published: July 2011

A prototype of miniature vapor compression heat pump system was introduced. On the basis of compressor, capillary, condenser and evaporator models, the steady-state model of air-to-water miniature heat pump system is developed with regard to energy and refrigerant inventory conservations among all these components. The results show that the relative error between prediction and experiment values is less than 5%, and the optimal match of condenser and evaporator lengths were obtained by simulation program.
Application the Cumulative Exergy Analysis to the Optimal Heat Exchange Process
Authors: Zhu Ping
Published: July 2011

This paper focuses on evaluation of the heat exchange process based on cumulative exergy analysis method. The case study chosen is the countercurrent heat exchange process that is widely used in the industrial processes. The optimal design is achieved by minimizing the annual total cumulative exergy consumption of the cold stream. The natural resource-oriented mathematical models are established in details. Obviously, the results from cumulative exergy optimization are imposed by the present state of the technology compared with the ones from thermoeconomics.
Interval Analysis Method of Uncertain Structural Systems Based on Random Model
Authors: Wang Zhao , Huang Min
Published: July 2011

The uncertain parameters of the structures are expressed by interval variables, and the governed equations of the structural system are obtained with the finite element method, then interval analysis is used to model the uncertainty in the static structural analysis and design. After the interval arithmetic integrated with random theory is studied, the confidence interval of structural response is achieved, and the approximate calculation is used with the method of Monte Carlo. Furthermore, by combining the interval variable of the structural response with confidence interval, an analysis method of uncertain structural systems is proposed based on the random model. The presented method can restrain expanding interval, and easy to engineering due to its convenient calculation.
Research on Protocol-Based Mechanism and Algorithm for Customer Collaborative Design Task Allocation
Authors: Song Li Jun , Zhou Kang Qu
Published: July 2011

Based on the task allocation problem in customer collaborative design ,which is a new product innovation mode, the task allocation was realized by using a task allocation mechanism based on the negotiation and a protocol was proposed for task allocation. Considering the effecting factors of the collaborative design, a decision-making algorithm based on the comprehensive evaluation was proposed in order to realize the optimal allocation of the task.
An Assessment of Subway Station Capacity
Authors: Xu Xin Yue , Liu Jun , Li Hai Ying , Zhao Lu Min
Published: July 2011

Each year, according to Chinese and European statistics, there are many serious injuries and even fatalities of travelers into subway transit stations. Consequently, it becomes more and more important for transit authorities to evaluate these facilities (platform, gates, stairs, escalators, etc.) under critical traffic conditions, such as rush hours or emergency situations. The purpose of this paper is to review existing research results, develop the main Framework of station capacity assessment and finally point out the key issues of subway station capacity assessment.
Research of Customization Model Based on MES
Authors: Wang Peng , Li Xue Jun , Huang Xin
Published: July 2011

Manufacturing execution system is the link in the process of enterprise implementation information integration.Structured simplified model of the virtual product list,improve efficiency of customized products management. Established model for segment customized products in time and space. Classified the parts and products which had the same specifications.These products can directly get from the warehouse and distribution.Classified the products that need to completely redevelopment at the same time. Attained the purpose of shorten the delivery time. And on this basis, designed customization model for products based on MES. Under the support of information exchange capabilities platform by manufacturing execution systems . Deliver customization model data to the production unit in time, to ensure that custom products completion on time, by volume and quality.
Research and Application of Inventory Management System of Foundry ERP Based on Multi-Agent
Authors: Tang Hong Tao , Zhou Jian Xin , Song Jian
Published: July 2011

By analyzing the characteristics of foundry enterprises and the features of multi-agent theory, this paper applies this theory in the management of foundry enterprise. A multi-agent model and a detailed multi-agent model of inventory management are constructed in this study. The KQML is adpoted to meet the requirements of communication between agents. This study set up KQML messages about data manipulation and then map these KQML messages to SQL clause. Based on this model, an inventory management system of ERP for foundry enterprise is developed. The successful application of this system proves that it is applicable to use the multi-agent theory to enhance the management of foundry enterprises.
DOA Estimation Algorithm in Switch Antenna Array with a Single Cycle of Sampled Data
Authors: Zhang Ke , Ma Peng , Zhang Jian Yun
Published: July 2011

For DOA estimation of coherent signals in switch antenna array (SAA), a new fast algorithm is proposed. Instead of conventional sub-space algorithm’s covariance matrix, a Toeplitz matrix is constructed with a single cycle of sampled data. It is proved theoretically that the ranks of the Toeplitz matrix is equal to the number of signal sources and has no relations with the coherency of the signal source. Through eigenvalue decomposition, signal and noise subspace are obtained respectively, then DOA estimation can be done by one-dimensional spectral peak searching according to the MUSIC algorithm. The theoretical analysis and simulation results demonstrate validity and superiority of the novel algorithm.
An Analytic Iteration Method of Geometrical Nonlinear Analysis for Frame Structures and its Application Program Research
Authors: Sun Lu , Zhao Rui , Li Rui
Published: July 2011

Static method and energy method are two mainly solution methods for structure calculation presently. Static method often appears insoluble complicated transcendental equations and continues hardly. Energy method can solve force analysis of complicated structure and it is a widely used method at present, but in general it is not exact. In this article, analytic iterative method is a calculation method of analyzing geometrical nonlinear of frame Structures, considering the influence of geometrical nonlinear in structure calculation, on foundation of the analytic method that expressed with deflection equation of pressure column with geometry parameter expression with the combination of traditional linear analysis method. And a calculating application program is written to calculate displacement and force of frame structure in the environment of MATLAB language in order to apply conveniently. Because this method is on basis of analytic method, its results have sufficient accuracy. At last, there is an example to explain.
Simulation Study of Converter Coherent Jet Oxygen Lance
Authors: Shen Ming Gang , Zhang Lei , Zhang Zhen Shan
Published: July 2011

In this paper, hydraulic model experiment is performed for comparing the agitation ability of the coherent blowing and the top-bottom blowing. And numerical simulation is implemented for studying the influence of the concomitant flow temperature and pressure on the core space of the main jet. And the results show that the agitation ability of the coherent blowing and the top-bottom blowing is considerable. And the core space of the main jet of lance increases along with the increasing of the concomitant flow temperature under a certain pressure.
Performance Analysis and Numerical Simulation in Elliptical Tubes
Authors: Zhang Song Bo , Lv Jing
Published: July 2011

By using the FLUENT software, the flow and heat transfer properties of several elliptical tubes were numerically studied. The mathematical models of the tubes flow field were established. The implementation incorporated a SMPLE-based semi-implicit solution algorithm that was applied to iterating calculation. Results shows that the surface heat transfer coefficient, temperature difference between inlet and outlet were all higher than circular tube, when mass flux equal to at inlet of elliptical tubes and circular tube and wall temperature was invariable. Therefore, the elliptical tube is a kind of effective heat transfer enhancement element.
Product distribution during Datong Coal Pyrolysis and Hydropyrolysis
Authors: Liu Quan Run , Xia Hao
Published: July 2011

Pyrolysis and hydropyrolysis of Chinese Datong coal was carried out at temperature from 350 to 650°C,under pressure of 2Mpa in a fix-bed reactor. The product distribution was determined, and gas evolution of coal pyrolysis and hydropyrolysis was also studied. The experimental results shows that coal conversion and water yield increase with temperature increasing during both pyrolysis and hydropyrolysis; tar yield increase during hydropyrolysis with temperature from 350 to 650°C, but the highest tar yield during pyrolysis is at temperature of 550°C. At high temperature area, CO、CH4 and C2+ has higher yield in hydropyroly than that in pyrolysis. The products distribution of pyrolysis and hydropyrolysis showed that the effect of H2 on coal thermal conversion only occurs at high temperature area.
Research on Feed Processing Parameters of the Cotton Comber
Authors: Ren Jia Zhi , Jia Guo Xin , Feng Qing Guo
Published: July 2011

For combed spun yarn of high quality, the feed amount per cycle and the bat weight have to be chosen correctly. When the feed amount per cycle and the bat weight are too low or too great, there is an effect on the combing efficiency, piecing quality, percentage of noil and quality of spun yarn. The influence of the feed amount per cycle and the bat weigh on combing efficiency, percentage of noil and piecing quality are analyzed theoretically. In order to investigate the effects of the feed amount per cycle and the bat weight on yarn quality (unevenness CV%, thin places, thick places and neps), The 14.6 tex yarn is spun on combing spinning system with E62 comber. The results of our investigations reveal that high combing efficiency and high quality yarn can be obtained with a lesser feed amount per cycle and a bigger bat weight on new type of cotton comber.
Effects of Cellulase Modification on Fiber Surface and Quality of Masson Pine Mechanical Pulp
Authors: Luo Qing , Li Xin Ping , Liu Ye
Published: July 2011

At present, paper industry has a lot of problems in China, such as the shortage of forest resources and high cost of pulping. Paper industry must be seeking high yield and low cost pulping process. In order to reduce the cost of mechanical pulp and increase the use of mechanical pulp, a lot of research and patent showed that the refining energy consumption of mechanical pulp would be further decreased using the corresponding enzyme to modify fiber of the raw materials before refining. The effects of cellulases modification on masson pine mechanical pulp were investigated in this paper. The modification conditions were as follows: the dosage of enzyme 75IU/g (to bone dry materials), temperature 500C, time 150min, pH value 5.5 and pulp concentration 15%. The effects of cellulase modification on the surface and quality of masson pine fiber of mechanical pulp were investigated by scanning electron microscope (SEM), atomic force microscopy (AFM) and fiber quality analyzer (FQA). It was found from the images of SEM that the original fiber surface was smoothly but markedly corroded after the cellulase modification. Moreover, the modification brought about more external fibrillation and longitudinal tearing during refining. AFM measurement results showed that the fiber surface roughness was improved after the cellulase modification because that the middle lamella, primary wall and outer layer of secondary wall were broken. The results of FQA measurement showed that the average fiber length increased slightly.
The Application of Fuzzy Analytic Hierarchy Process in Community Informatization Level Evaluation
Authors: Wu Jian Jun , Wang Yong , Xie Qing
Published: July 2011

Because of unscientific evaluation methods for the community infomatization level, the paper analysis various factors affecting the community infomatization level, according to the full life-cycle thinking for infomatization construction, establish the evaluation index system of the community infomatization level and use fuzzy analytical hierarchy process to build a evaluation model of the community infomatization level, which can help us to make an objective fair and accurate comprehensive evaluation for the community infomatization level, help to further development and improvement of community infomatization construction. Finally apply this model to a certain community evaluation of community infomatization level, and give the application process.
A Study on Speed of Fluid in Swirling Abrasive Jet Nozzle and Drilling Hole Performance
Authors: Zhang Dong Su , Liu Li Hong
Published: July 2011

By placing the whirling element in the nozzle body, swirling abrasive jet has been produced. The speed function of spiral groove and swirling contraction segment in inner of nozzle are analyzed. And the formulas of speed function are obtained. It is seen that movement of fluid in the spiral groove is regarded as spiral one-dimension axial symmetry, movement of fluid in the swirling contraction as spiral two-dimension axial symmetry. The swirling abrasive jet system has been established. The production method and the drilling test system of the swirling abrasive jet are introduced. The drilling mechanism of the swirling abrasive jet is analyzed. Through experiment, the effects of the whirling element structure and the jet parameters on drilling performance are studied. The results indicated that in the case of nozzle non-rotation, under the working pressure of 10 MPa, swirling abrasive jet can drill a deep hole on coal block of which Polodyakonov coefficient f is about 4, and that the diameter of the hole is 20~30 times the size of the nozzle exit diameter. So the swirling abrasive jet has a good drilling performance.
Analysis Methods of Bottom Pressure for Fractured-Vuggy Reservoir
Authors: Chang Bao Hua , Xiong Wei , Gao Shu Sheng
Published: July 2011

It’s difficult to measure bottom pressure in the fractured-vuggy reservoir, and measuring cost is usually high; In this paper, using the modified Beggs-Brill method, the variety of wellbore pressure has been calculated and analyzed. Results show that the variety of wellhead pressure is consistent with that of bottom pressure, and the variety of wellhead pressure is greater than that of bottom pressure. Thereby a simple method of predicting bottom pressure through wellhead pressure is established. Through example calculation, it’s confirmed that this method has a certain reliability and practicability.
Numerical Simulation of Unidirectional Solidification on Ingot of Heavy Plate Based on MARC
Authors: Ao Guang Wu , Shen Ming Gang , Zhang Zhen Shan
Published: July 2011

Unidirectional solidification technology is a producing process of cast large-sized ingots industry and control the single orientation microstructure of solidification. Combined with the conditions of production, casting the 23t ingot of unidirectional solidification for experiment, we made numerical simulation of the 23t unidirectional solidification ingot with MARC; these are consistent with the result of experiment, and testified the simulation is feasible, offered gist for the design of the mould and casting, and took on reference to the product field.
Algorithm for Rapid Slicing Based on Coordinate of STL Model
Authors: Mu Xiao Yun
Published: July 2011

Based on exist algorithm for STL model slicing. We proposed an algorithm that is based on STL model coordinate layering. When loading STL model, the algorithm layers the model according to the apex coordinate Z of each triangular facets. then calculate intersections according to the topologic relationship among interval edges and apexes of triangular facets in layers. Produce CLI files for rapid prototyping. The method optimized data frame and improved efficiency of slicing.
A Study of Springback of Sheet Metal Formed Parts Using ANSYS
Authors: Wang Xuan Zhi , Masood Syed H. , Ng Daron , Dawwas Omar
Published: July 2011

Springback is one of main reason for inaccuracy of sheet metal formed product. Therefore prediction of springback is very important for production of precise products. Springback is an elastic material recovery after unloading of the forming tools, and causes variations and inconsistencies of final part dimensions. This is affected by various parameters involved in the process of sheet metal forming. The main aim of this paper is to investigate the springback of finished part by analysing and controlling the effects of the control parameters on the springback of advanced high strength steels (AHSS). This is done by modelling a deep-drawing process and analysing the results as determined on ANSYS finite element analysis software.
Modelling of Surface Properties of Selected Silicate System
Authors: Dobrovská Jana , Dudek Rostislav , Vitásková Silvie , Kavička František
Published: July 2011

Presented paper deals with investigation of selected ternary oxidic system with high content of silicates from the viewpoint of surface properties. Research was focused not only on experimental investigation, but mostly on theoretical modelling of surface tension. This approach was chosen due to absence of compact set of information from the area of heterogeneous processes at high temperatures. It is moreover very often difficult to access appropriate data. Surface propertieswere investigated by sessile drop method. Afterwards calculation was made with use of selected semi-empirical models and obtained outputs were confronted with experimentally obtained data. Modelling comprised also temperature dependence of surface tension and influence of SiO2 on its values.
Optimal Tool Sequence Selection for Semi-Finishing of Mold Cavity
Authors: Pan Xin , Cai Yu Jun , Qi Tie Li
Published: July 2011

This paper proposes an efficient method to the lowest cost tool sequence for semi-finishing of mold cavity on a 3-axis mill machine. Suppose that the rough machining has completed, so the redundant slice is thin enough and can be removed with a single pass of the semi-finishing cutter. To guarantee the cutting operations do not gouge the desired surface, there is a largest cutter which can be used at any part of the surface. On the other hand, to improve efficiency, large cutter should be priority selected. Dynamic programming finds a near optimal tool sequence based on the approximate evaluation of machining cost.
Numerical Simulation of Three Dimensional Extrudate Swell Using Finite Element Method
Authors: Xu Xing Ming , Qin Sheng Xue , Wang Wei
Published: July 2011

The precise prediction of extrudate swell is significant to the control of melt flow and the quality of final products. A mathematical model of power law flow for polymer extrusion is investigated. The penalty function formulation is introduced to the finite element model and the free surface is updated with streamline equation in a decoupled method. A proper penalty constant is determined by comparison of numerical results with different penalty constants. The velocity field is obtained and the distribution of velocity on different cross sections is compared. The effects of volumetric flow rate and die shape on extrudate swell ratio are discussed. The simulation results are very important for the process and die design of the polymer extrusion.
Numerical Simulation of Welding Temperature Field on Side Beam of Train Bogie
Authors: Ren De Liang , Fang Min , Li Jian , Yu Shen Wei , Guo Hao , Qi Fang Juan
Published: July 2011

Numerical simulation based on finite element modeling is used widely for the prediction of welding residual stress and distortion. Considering this method, the accuracy of the ultimate result of the residual stress and distortion field is depended greatly on the accuracy of the welding temperature field. The APDL languages of ANSYS procedure was used in this study. In order to model the addition of the filler to the weld, element birth and death technology was selected. It well performed to simulate the moving of the heat source and the process of transient thermal convection. The results show that the change process and the distribution of the welding temperature field agree well with the weld reality.
Gas Bubble Behavior Model in Adhesive Bonding Using Thermosetting Polymer
Authors: Nie Lei , Zhong Yu Ning , Zhang Ye Peng
Published: July 2011

Gas bubbles entrapped in polymer intermediate layer often lead to voids which are severe defects of adhesive bonding qualities. Although the empirical method had been used for a long time to eliminate the bubbles, theoretic analysis considering the bubble behavior during bonding process is more preferable because of the better universality. The interrelationships between processing parameters and bubble deformation were investigated. A theoretic model describing those interrelationships was developed reasonably using gas diffusion theory to predict the bubble behavior. The mathematic equations of this model were deduced and the solution was obtained with some proper simplifications. Experiments under different conditions were carried out and the experimental results were contrasted with the theoretical predictions. It was obvious that when choosing temperatures and pressures carefully, the model could predict the bubble behavior accurately.
Drawing Process Analysis for Electrodeposited Nickel Coating by Finite Element Method
Authors: Zhou Li Qun , Li Yu Ping , Fu Cai Ming
Published: July 2011

A finite element method is used to simulate the deep drawing processes of nickel coating with steel substrate into battery shells. The Belytschko-Wong-Chiang shell elements are used and the kinematical work hardening model is adopted, while the ties with failure contact criterion is given to the coating and substrate interface. The stress-strain field and interfacial stresses in the drawing processes are obtained. The nickel coating appeared to be yielded in the drawing processes, of which the maximum effective stress reached 241MPa, and the biggest effective strain reached 0.7524. The interfacial stresses in the coating and substrate varied during the drawing process, and their maximal values reached 40MPa in compressive state.
Influence of pH Value and Precipitant on Zn2SnO4 Formation via Co-Precipitation Method
Authors: Wu Yu Shiang , Tsau Min He
Published: July 2011

Nanorod-shaped zinc stannate Zn2SnO4 (ZTO) with great photocatalytic activity was successfully synthesized via a co-precipitation method. In this paper, a strong base (NaOH) and a weak base (Na2CO3) are adopted as precipitants in order to form the precursor precipitate. The titration endpoints are fixed at pH6, pH8, and pH10 in order to adjust the solution precipitant quantity. Dependent variables above were not seen in other research before. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results show that the powders synthesized were ZTO nano-particles. Photocatalytic activity of the powders was measured utilizing a photocatalytic degradation reaction with methylene blue (MB) solution. The smallest particles were obtained by utilizing NaOH as a precipitant and adjusting pH to 6. Based on TEM images, the ZTO had nano-rod particle morphology. However, when precipitant Na2CO3 was utilized, particles agglomerated together, reducing specific surface area. Hence, the former sample shows better photocatalytic activity than the latter one. Consequently, powders titrated to pH6 by precipitant NaOH and calcined for 1 hour will form partly nano-rod particles with slight agglomeration, increasing the specific surface area of ZTO and bringing about the best photocatalytic characteristics.
Effect of Phosphorus on Microstructure and Properties of Al-Mg2Si Alloys Subjected to Electromagnetic Stirring
Authors: Ren Yu Yan , Li Ying Min
Published: July 2011

Al-Mg2Si composite has such advantages as low density, high elastic modules, simple manufacture technology and low cost. However, its strength and ductility need to be enhanced. Thus, the alloying element P was added to control the microstructure of Al-Mg2Si alloy and furthermore improve the mechanical properties of the composite. The experimental results show that the microstructure of the Al-Mg2Si alloys subjected to electromagnetic stirring can be significantly refined and the mechanical properties of the alloy get improved due to the addition of phosphorus. It is found that the best modification effect can be achieved when the adding amount of phosphorus is in the range from 0.7% to 1.1% and the holding time is about 15 minutes, and the mechanical properties of the Al-Mg2Si alloys get markedly enhanced.
Wrinkling Identification and Wrinkle Distribution of a Tube in Hydroforming with Radial Crushing
Authors: Liu Xiao Feng , Yang Lian Fa , Zhang Yu Xian
Published: July 2011

Hollow parts with variable cross-section are widely used in the area of automotive and aerospace industries due to their excellent properties. Wrinkling is one of the most common forms of instability in the process of manufacturing the parts. The minimum curvature of the cross-section profile of bugled workpieces is proposed in this paper to as a wrinkling indicator to characterize the form and extent of the wrinkle. The wrinkle distribution of 1Cr13Mn9Ni1N stainless steel tube in hydroforming with radial crushing under linear and constant hydraulic pressures is analyzed and the influence of the bulging methods on the wrinkling is investigated via finite element simulation. The results indicate that wrinkling under constant hydraulic pressure is more obvious than that under linear one, wrinkling in hydroforming with radial crushing is more serious than that in free hydro-bugling, wrinkling on the cross-section away from the middle cross-section is more distinct and the wrinkling on the side edge is obvious than that on the bottom of the bugled workpiece.
Thermomechanical Load Study on FGM Clad Hot Forging Die under Mechanical Press
Authors: Wang Hua Jun , Sun Yu Zhu , Wu Yan Zhao , Wang Hua Chang
Published: July 2011

Hot forging die bear periodic thermal load and mechanical load during service, and bad work environment makes the service life of dies generally short. Hot forging die damages mainly appear in temperature fluctuation zone, and gradient composite materials cladding process can be used to do surface treatment on homogeneous hot forging die. This process can greatly decrease the peak value of temperature and stress and prolong the service life of hot forging die. FE model of hot forging process under mechanical press was build based on Deform-2D, temperature and stress field of homogeneous hot forging die and FGM surface cladding hot forging die under mechanical press were compared. Then the characters of thermomechanical load based on FGM surface cladding hot forging die were described, which provided foundation for design and manufacture of FGM hot forging die.
Study on Mathematical Model of High Speed Milling Force for Plastic Mold Steel 3Cr2Mo
Authors: Xiao Jun Min , Xu Ying
Published: July 2011

Mold steel 3Cr2Mo has been used widely in manufacturing of plastic mold formed parts, owing to fine mechanical properties. However, it is also very difficult to cut mold formed parts of steel 3Cr2Mo due to high hardness. Ordinary NC cutting method of steel 3Cr2Mo is unable to relate to modern mold manufacturing due to bad cutting property, so it is extremely significant for improving cutting property of steel 3Cr2Mo to study the high speed milling technology. On the basis of improving the traditional cutting force formula, the mathematical model of high speed milling force for steel 3Cr2Mo was derived and solved by using the experimental data and constructing matrix equation based on MATLAB software. Comparing with experimental data, the error of mathematical model of high speed milling force could be controlled within 6 percent. Due to high precision the model of high speed milling force can meet practical engineering requirement and has great value in the fields of CAD/CAM/CAE.
Experimental Study on High-Speed Milling of SiCP/Al Composites
Authors: Ge Ying Fei , Xu Jiu Hua , Fu Yu Can
Published: July 2011

Tool life and tool wear, cutting forces and cutting temperature, surface finish, chip formation and surface generation were investigated when milling SiCp/2009Al composites at the cutting speed of 1200m/min using PCD tools. The results showed that PCD tool life was 150min when the 0.1mm tool wear criterion was chosen. PCD tool mainly suffered from tool grain breaking-off, chipping, abrasive wear, micro cracks and adhesive wear due to he very high-frequency impact and scrape of SiC particles. The peak value of the cutting force Fy (the radial direction) was over 1300N and the cutting vibration was very severe. The cutting temperature was 523.7°C. Pits, voids, matrix tearing and scratch were the main defects on the machined surface. The deformation layer thickness was about 20-35μm. The chip for the vol.20%SiCp/2009Al composite took the form of flow type and the mechanisms of the chip formation were the combination of dynamic behavior of voids/micro-cracks and adiabatic shear. For the vol.35%SiCp/2009Al composite, the chip was non-continuous and had the tendency of saw-toothed type. Material swelling and side flow, tool-workpiece relative vibration, feed rate and tool nose radius, removal mode of SiC particles were the main mechanisms of surface generation.
Edge Drop Control Technology of 4-Hi Tandem Cold Rolling Mill on the Premise of Considering Roll Grinding Accuracy
Authors: Yang Guang Hui , Cao Jian Guo , Zhang Jie , Yin Xiao Qin , Jia Sheng Hui , Zeng Wei
Published: July 2011

For gaining strip edge drop controllability and increasing roll grinding precision, the edge drop control work roll (EDW) was developed and designed in 1700 mm tandem cold rolling mill. During the rolling trial, the roll configuration between EDW and conventional backup roll didn’t match well because of the large fluctuation of strip edge drop, the lower shape control ability and non-uniform roll wearing, so the new roll configuration between EDW and varying contact backup roll (VCR) was proposed. After analyzing by finite element model, the result showed that the roll system configuration of VCR and EDW was better by 10.7% larger roll gap crown adjustable scope, 19.1% larger roll gap stiffness characteristics and 21.6% smaller pressure peak between rolls than before. The new roll system configuration has been applied to 1700 tandem cold rolling mill at WISCO after industrial testing.
A Study on Novel Gas Atomization Device for Preparing Ultra Fine Metal Powder
Authors: Dang Xin An , Wang Li Li , Yang Li Jun
Published: July 2011

On the basis of technologies of gas atomization, supersonic gas atomization, surface effect of electric charge and jet, we design a new-style device of two fluids atomization with the combination of solid atomization and electric field utilizing a LAVAL nozzle, a delivery tube of sectional type and the electrical field dispersion technique. The soldering tin of 63 A was atomized with the air, and the powder prepared was analyzed by optical granularity analyzer, nanometer magnetic particles and Zeta potential analyzer. The results show that the particle size with less than 8μm can reach 75%; the average particle size is 1.7612μm, and the first peak in the distribution curve is about 500 nm, which is an order of magnitude smaller than that the existing reported peak. The compound atomization device can refine the particle size of powers effectively, improve uniformity, yielding rate, and the purity of atomized powders and has a significant effect on atomizing, thus provides powerful supports for preparing ultra fine metal powders with high efficiency and low energy consumption and has a good prospect in application.
A New Method on Choosing Tool Materials at High Speed Machining
Authors: An Hu Ping , Rui Zhi Yuan , Wang Rui Feng , Guo Jun Feng
Published: July 2011

Aiming at the key problem of tool choice presented at high speed machining, this paper analyses the characteristic of existing materials of high speed machining tool from three aspects of mechanics, physics and chemistry, and sums up the cutting property of work materials combining with some experimental results and literatures. By integrated comparison of the property of materials of tool and workpiece, a method of choosing tool material for corresponding to workpiece is offered. Finally, some matched materials of tool and work are provided for convenient choice, which can acquire better effects than used testing or experience ways and means.
Effects of Rotating Electromagnetic Field on Solidification Microstructure of ZA27 Alloy
Authors: Wang Zhi Hua , Zhu Ming , Xu Guang Ji
Published: July 2011

In the present, by using rotating electromagnetic field (REMF) equipment, the effects of REMF for crystal growth processes in cast ZA27 alloy were investigated. It was found that the growth of the primary and secondary dendrites was restrained by alternative REMF and solidification microstructure transformed from dendrite to non-dendrite and globular crystal. The grain refinement effects were further improved with increasing of voltage.
The Discussion of {111}∥ND Formation Mechanism
Authors: Wang Tao , Leng Yan Hong , Chen Lian Sheng
Published: July 2011

{111}∥ND forms at deformation stage, it is connected with main slip systems, by analyzing main slip systems and its performance, {111}∥ND formation mechanism can be drawn. In addition, by analyzing cold reduction’s effect on main slip systems, the relationship between {111}∥ND and cold reduction can be drawn, and some experiments can be explained.
Preparation and Characterizations of NiTi Intermetallic Coatings
Authors: Deng Chun Ming , Liu Min , Deng Chang Guang , Dai Hong Liang , Zhou Ke Song
Published: July 2011

Much attention has been paid to NiTi intermetallic coating for enhancing cavitation erosion resistance property due to its shape memory effect. In this paper two processes were used to deposit NiTi intermetallic coatings. Process 1 was the deposition of NiTi intermetallic coating using warm spray process with NiTi intermetallic powder as feedstock, and solution treatment was subsequently performed. Process 2 was a mixture process of warm spray and laser treatment. Ni-Ti coating was first deposited via warm spray process with Ni-cladding Ti as feedstock, and laser-treatment was performed to realize the alloying of Ni-Ti. The microstructure and phase compositions for NiTi intermetallic coatings were characterized by means of SEM and XRD. The fundamental properties for NiTi intermetallic coatings were also analyzed.
Modeling of Resistance Spot Welding Process Using Nonlinear Regression Analysis and Neural Network Approach on Galvanized Steel Sheet
Authors: Luo Yi , Li Chun Tian , Xu Hui Bin
Published: July 2011

Modeling of resistance spot welding process on galvanized steel sheet was investigated. Mathematical models developed by nonlinear multiple regression analysis and artificial neural network approach were employed in the prediction of welding quality factors, namely nugget diameter, penetration rate and tensile shear strength, under some welding conditions. According to the prediction models on quality, the prediction systems of welding process parameters were formulated respectively on the basis of Newton-Raphson iterative algorithm and cascade forward back propagation algorithm in order to obtain the desired welding quality. The results showed that the prediction precision of cascade forward back propagation algorithm was higher than Newton-Raphson iterative algorithm. The current duration had the largest prediction error, followed by electrode force and welding current. Therefore, it was concluded that the current duration was the most difficult parameter in prediction system of welding process in order to obtain the desired welding quality.