bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of Grey Correlation Analysis on Tool Selection
Authors: Zhang Sheng Wen , Lan T.X. , Fang Xi Feng , Jia W. , Yang C.Q.
Published: March 2010

Tool selection is the important content of CAPP, and a great many influence factors and selection principles must be considered during tool selection. For the unreasonable phenomenon during tool selection and usage in present manufacturing enterprise, first the rule reasoning and fuzzy theory method are used to select proper tool set according to the processing conditions, then grey correlation analysis method is used to calculate the weight value of each tool and compare superiority of the these tools, and the best tool in existing conditions is obtained. Grey theory is used in tool selection to work out the problem of insufficient and incomplete information in the process of tool selection, and the cumbersome factors are simplified, the accuracy and efficiency of tools selection are improved. The research result has all-right reference meaning to other decision-making systems.
Design and Analysis of Big-Character Printer
Authors: Meng Ai Hua , Li Ming Fan , Zhou Jian Jun , Pan Yu Liang
Published: March 2010

The Big-character printer is a dot-matrix print equipment used in industry field. The print head is the key part of it. Sixteen jet valves are arranged in three lines alternated regular framework. Every valve is driven by giant magnetostractive actuator (GMA). The dynamic characters of valve body and GMA have been studied in the paper. The square wave response experiment shows that the valve bandwidth is more than 400Hz. The response plot has a good agreement with the simulation result. Meanwhile, the print dots are clear. Therefore, the BCP based on GMA could fulfill the requirement.
The Study on Suppression of Dimples in Digital Multi-Point Stretching Process
Authors: Zhang Chuan Min , Fu Wen Zhi , Li Xiao Da , Li Ming Zhe
Published: March 2010

In this paper, the basic theory of multi-point stretching process was introduced, the process of multi-point stretching of saddle part was simulated, the generation and suppression of dimples were studied [1~3]. The results showed that dimple is specific defect in the multi-point stretching process; the dimples can be suppressed effectively by elastic cushion technology. Thicker elastic cushion is more effective to suppress dimples, but the error between formed workpiece and objective shape will get large. By adopting elastic cushion with appropriate thickness, workpiece with smooth surface can be obtained and the forming error is small.
Influence of Preparing of Specimen on Internal Stress Measurement of Aluminum Alloy Thick Plate
Authors: Liao Kai , Wu Yun Xin , Gong Hai
Published: March 2010

The cut, a main preparing means of specimen, will cause a difference in stress distribution between thick plate and the specimen, so this article focuses on the topic of evaluating impact of the cut on stress measurement results. Firstly, the real surface stress distribution of the plate and specimen were determined by X-ray diffraction (XRD) and FEM. Secondly, according to the specimen dimension and machining procedure, the influence of the cut on internal stress measurement is obtained and compared with the FEM results. The conclusions are as follows: (1) the normal stress of cut plane steeply decreases and the stress gradient descends along with distance away from the cut. The range of distance is approximately one-thickness of specimen. (2) In order to obtain stable and reliable results, the plane size of specimen is taken three times larger than the thickness. (3) The milling processing of layer removal method (LRM) can change the surface stress state of specimen, but the machining effects on residual stresses can be removed by properly choosing milling parameters.
An Adaptive Local Meshfree Updated Lagrangian Approach for Large Deformation Analysis of Metal Forming
Authors: Gu Yuan Tong
Published: March 2010

The large deformation analysis is one of major challenges in numerical modelling and simulation of metal forming. Because no mesh is used, the meshfree methods show good potential for the large deformation analysis. In this paper, a local meshfree formulation, based on the local weak-forms and the updated Lagrangian (UL) approach, is developed for the large deformation analysis. To fully employ the advantages of meshfree methods, a simple and effective adaptive technique is proposed, and this procedure is much easier than the re-meshing in FEM. Numerical examples of large deformation analysis are presented to demonstrate the effectiveness of the newly developed nonlinear meshfree approach. It has been found that the developed meshfree technique provides a superior performance to the conventional FEM in dealing with large deformation problems for metal forming.
Research of Geometric Parameters Related to TRB Uniaxial Tension
Authors: Li Yan Hua , Du Ji Tao
Published: March 2010

A discrete method was used to separate the thickness transition zone (TTZ) with continuous change of thickness. Uniaxial tension models, with different lengths of TTZ and different thickness ratios, were simulated to obtain the effect of geometric parameters on TRB uniaxial tension. The results showed that both length of TTZ and ratio of thickness had effect on elongation percentage. The elongation percentage increased significantly on the condition that the length of TTZ was 80mm, which was closed to total length of specimen (120mm); Thickness ratio had more effect on movement during uniaxial tension. The results could provide important technical reference for formulation of TRB uniaxial Tension Test standard and promote the light-weight application of TRB on the automobiles.
The Drum Height Detection Model of the Shearer Cutting Memory Program Control
Authors: Sun Yue Hua , Liu Chun Sheng , Liang Xiao Ming , Yan Xiao Lin
Published: March 2010

The drum height was detected reliably, one of the main parameters for requirements of the shearer cutting memory program control was obtained. According to the principle of the drum lifting mechanism, two kinds of sensor detection conversion mathematical model based on the rocker angular displacement and the lifting cylinder linear displacement were established, the mathematical relation between the drum height and the sensor detection quantity and precision was derived, and the error of two kinds of detection was comparatively analyzed, therefore the theory basis to choose the sensor tape and precision to shearer cutting memory program control is provided.
Development of CAD System and Forming CAE of Porthole Extrusion Moulds for Hollow Aluminum Profile
Authors: Chen Ze Zhong , Li Zhuo Hua
Published: March 2010

According to the design principles and structure characters of the plane porthole extrusion moulds of hollow aluminum profiles, the general structure of a UG based CAD system for porthole extrusion moulds of aluminum profiles is designed after system analysis and plan, by adopting the object oriented technology and OMT (Object Modeling Technology) methods. Then the CAD system is developed based on UG software with the help of UG / Open GRIP re-developing tools. The sample design approved that it is quite convenient to design parametric porthole extrusion moulds CAD model by using the developed CAD system. In the last part, the FVM (Finite Volume Method) is used to simulate the process of extrusion. The metal flow, the equivalent stress distribution are analyzed for future optimization of the porthole structure.
Two Dimensional Vibration-Assisted Micro-Milling: Kinematics Simulation, Chip Thickness Computation and Analysis
Authors: Ding Hui , Chen Shi Jin , Cheng Kai
Published: March 2010

Two dimensional vibration-assisted machining is applied into micro-milling to improve cutting accuracy and prolong tool life. In this paper, the tool tip path of two dimensional vibration-assisted micro-milling (2-D VAMM) with different vibrating parameters is simulated and analyzed. And the computation module of chip thickness in 2-D VAMM is proposed, based on which the chip thickness characteristics is investigated using two evaluating indicators: free time ratio (FTR) and amplitude ratio (AR). The effects of vibrating parameters on FTR and AR are studied with the help of Full Factorial Design and analysis of variance. It is found that FTR can be increased by increasing the ratio of amplitude in normal direction to the feed and the ratio of frequency in normal direction to spindle speed, while AR will be enlarged with increase of the ratio of amplitude in feed direction to the feed and the ratio of frequency in feed direction to spindle speed. The simulation studies are the foundation for calculating cutting force, tool wear and surface roughness in 2-D VAMM and can also guide the further experiment.
3D Loading Path-Generating Method for FEM Simulation of Incremental Sheet Metal Forming Process
Authors: Xu Yan , Li Shuang Gao , Gao Lin
Published: March 2010

Incremental forming of sheet metal is difficult to be simulated for its complicated 3D loading path. In this work, an acceptable approach to generate 3D loading path, called “virtual guiding model method” is accomplished. The method, which has the similar idea with the conventional copy mill, is based on FEM and the basic principle of kinematics. With the help of the method, multi-stage incremental forming of a drawing typed square cup was simulated in the FEM software-PAMSTAMP and experimented. Through measuring the thickness distribution the vertical edge of the cup, the most difference between them is less than 0.05mm, which is satisfied with engineering request, and the results shows that the 3D loading path generating method is one of the most effective way to realize the incremental forming simulation.
The Study on Vibration of Marine Riser under Deep Water
Authors: Han Chun Jie , Yan Tie
Published: March 2010

With the development of deep water drilling engineering, marine riser has become the important equipment. With the increase in water depth, the failure of marine riser is very serious, the vibration is the main reason. According to the actual situation, the model of marine is set up, the rule of lateral vibration is obtained. The result is helpful to avoid the phenomena of resonance of marine riser under wave loads.
Numerical Analysis on Hot Stamping of B Pillar Reinforcement of Automobiles
Authors: Zhang Zhi Qiang , Ye Zhong Chao , Zhang Yi Sheng , Li Jian
Published: March 2010

Hot stamping of ultra high strength steel offers the possibility to reduce the weight of automobiles, while meeting the safety requirements. In hot stamping processes, the blank is hot formed and quenched in a water-cooled tool to achieve high strength. Hence, the temperature distribution of the blank during the process is very important for designing the tools with necessary cooling capability. In this paper, PAM—Stamp software was employed to build the hot stamping FE model of the B pillar reinforcement of passenger cars. Through the thermo-mechanical coupling analysis, the temperature distribution of the blank was obtained. The results show that the temperature in the holding area of the blank decreases quickly, whereas the side wall and bottom are cooled slowly. The inhomogeneous temperature distribution of the blank will cause the material unevenly flow during the forming process. Therefore, maintaining uniform temperature distribution and fast cooling of the blank are crucial for the cooling system of the tools.
Multi-Scale Numerical Simulation of H62 Brass for Hot-Extrusion Process
Authors: Xiao Yan Hong , Guo Chen , Tian Xiao Kang
Published: March 2010

Thermal deformation process of H62 brass is studied, multi-scale simulations of macro-forming property and microstructure distribution are carried out for the hot-extrusion process of double cups part with flange utilizing numerical simulation technology, the process parameters are determined and the microstructure of extruded parts is predicted. The constitutive equation of H62 brass under high temperature deformation is established with isothermal compression test, and the results indicate that the flow stress accords to Arrhenius hyperbolic sine functions. The model of microstructure evolution during hot-deformation is founded and the influence of process parameters on microstructure is revealed. The microstructure prediction on extruded part shows that the simulated results agree well with the experimental results. The high-quality products are obtained using the optimal process parameters.
Three-Phase Power Factor Correction Converter Based on One-Cycle Control in Aircraft Electric Power System
Authors: Nan Yu Rong , Meng Na
Published: March 2010

Traditional three-phase PFC converters based on one-cycle control (OCC) exhibit instabi-
lity at light load conditions.This will cause much more harmonic current which is harmful to the syterm.To overcome this disadvantage, this paper introduces a modified three-phase power factor correction(PFC) converter based on one-cycle control in aircraft electric power system. The input voltage multiplies a gain and its result is added to the actual sensed current,then the sum of them is compared with the sawtooth waveform to yield switching signal.This is the modified contorl mathod.
Finally the MATLAB simulations at heavy and light loads as well as the transfer between them are carried. The simulation results show that the improved control circuit can achieve unity power factor and exhibit stability at light loads.
The Stiffness Analysis and Modeling Simulation of Ball Screw Feed System
Authors: Wu Qin , Rui Zhi Yuan , Yang Jian Jun
Published: March 2010

The computer numerical control (CNC) machine tool was investigated and the dynamics model for the servo feed system was established. Based on the fixing constraint of the ball screw, the mathematical models of axial stiffness and torsion stiffness are constructed. According to the effects of stiffness on the dynamic performance, the simulation model for CNC machine tool feed system with stiffness considered was set up by the dynamic simulation tool Simulink, and a curve representing the performance of the system was obtained. To reduce the effect of stiffness on the system, the feedforward control strategy is used for stiffness compensation. The simulation results show that the stability and response performances of the system are improved and the steady-state error of the system is reduced by the control strategy.
Moment Stability of Stochastic Regenerative Cutting Process
Authors: Zhou Xiao Qin , Wang Wen Cai , Zhao Hong Wei
Published: March 2010

The stochastic uncertainties of regenerative cutting process (RCP) are taken into consideration, and both cutting stiffness and damping coefficients are modeled as two stationary stochastic processes. The eigenvalue equations are established for the stability analysis of stochastic RCP, corresponding to the differential equations of the first and second order moments. Thus the stability analysis of stochastic RCP is transformed into that of the first two order moments. The influence of stochastic uncertainties on the cutting stability of RCP is discussed. The numerical experiments have verified that with the increase of stochastic uncertainties, the cutting stability boundary was shifted downwards significantly, and the number of lobes was also multiplied.
Simulation of Void Defect Evolvement during the Forging of Steel Ingot
Authors: Chen Kun , Yang Yi Tao , Liu Ke Jia , Shao Guang Jie
Published: March 2010

Simulation method of void defect evolvement during the forging of steel ingot was determined by comparing simulated and experimental results of void closure in the cylinder specimens during forging. Calculation results of long and short void defect evolvement during forging indicated that effective strain required for void closure was induced by the integration of stress. The closure of tetrahedral void is the most difficult with the maximal values of critical reduction on void closure during forging, on the basis of which, theory basis is provided for making forging process.
Generation Mechanism of Micro/Nano Machined Surfaces Based on Molecular Dynamics
Authors: Tang Yu Lan , Liu Qiang , Wu Yu Hou , Zhang Ke
Published: March 2010

A three-dimensional model of molecular dynamics (MD) was employed to study the nanometric cutting mechanism of monocrystalline copper. The model included the utilization of the Morse potential function to simulate the interatomic force. By analyses of the snapshots of the various stages of the nanometric cutting process, the generation and propagation of the dislocations around the tool are observed. Some of these dislocations are observed to travel through the entire depth of the workpiece. Those that could most escape completely through the machined surface due to elastic recovery were found to introduce atom step on the machined surface. By analyses of the cutting forces during the entire nanometric cutting process, significant fluctuations are observed in the cutting force curves. The stress distribution plots of the various stages of the nanometric cutting process show that the mechanism of chip formation is significantly different from the conventional shear ahead of the tool in the case of a polycrystalline material. Most atoms ahead of tool are compressed, but forces of one or two layers atoms contact the cutting tool are tensile. With the chip formation, a small tensile zone ahead of tool generates in the compression zone and moves with the tool.
Operation Mode for Personnel Integration in Manufacturing System Based on Product Life Cycle
Authors: Liu Shuang , Liu Fei , Yan Ping
Published: March 2010

The function integration, process integration and information integration of the manufacturing system are all in need of the support of the personnel integration. But the complicated relationship among personnel has caused difficulties in personnel integration. In order to analyze the correlation between personnel in manufacturing system, an analysis method based on the relation degree matrix was proposed, meanwhile the personnel in manufacturing system was classified according to the product life cycle(PLC). The above work has paved the path for the further development of a kind of operation mode for personnel integration in manufacturing system based on PLC (MOPI). The mode is composed of four layers, which are the target layer, the PLC layer, the personnel layer, and the supporting system layer. The above mode was implemented in a local manufacturing enterprise, and positive application effect was achieved.
Using Efficiency Function in Analyzing the Ability of Flatness Control for a Cold Mill
Authors: Yan Qin Tai , Zhang Jie , Song Mu Qing , Mi Kai Fu
Published: March 2010

Analyzing a mill’s ability of flatness control has two purposes, one is finding the feather of a mill, and the other is making a judgment that whether a flatness error can be eliminated. But using classical method is hard to form a correct judgment when the error is complicated. Based on applying efficiency function in finding the property of each flatness actuator, a new method is developed to describe a mill’s comprehensive ability of flatness control. And we found the factors which contribute to whether a mill can weaken a certain flatness error. Practical application shows the new method is feasible.
Performance Assessment on Base-Isolated Smart Material-Structure System by Using Magnetorheological Fluids
Authors: Chen Bo , Zheng Jin , Wang Jian Ping
Published: March 2010

The feasibility of using MR fluids to develop a smart material-structure system and thereby to prevent structure from catastrophic damage is actively carried out in this study. The MR smart fluids are utilized to develop a smart damper with controllable parameters and the mechanical model of MR devices is presented by involving the effects of damper's axial stiffness. The interaction of a smart material-structure system is analyzed through the numerical integral and iteration. The vibration mitigation of the dynamic responses of an engineering structure with the smart coupled system is conducted based on the intelligent fuzzy control for performance evaluation. It is observed that the structural internal forces such as shear forces and bending moments can be remarkably mitigated with the protection of the smart system.
The Novel Compound Evolutionary Optimization Algorithm with Hybrid Discrete Variables and its Application to Mechanical Optimization
Authors: Luo You Xin
Published: March 2010

To overcome the problem of low convergence speed and sensitivity to local convergence with the traditional Artificial Fish-swarm Algorithm (AFSA) to handle complex functions, a novel compound evolutionary algorithm, called AFS-EMPCEOA, was introduced which is combined Artificial Fish-swarm Algorithm with the Elite Multi-parent Crossover Evolutionary Optimization Algorithm (EMPCEOA) that is GuoTao Algorithm improved by elite multi-parent crossover method. AFSEMPCEOA algorithm program with hybrid discrete variables was also developed. The computing example of mechanical optimization design shows that this algorithm has no special requirements on the characteristics of optimal designing problems, which has a fairly good universal adaptability and a reliable operation of program with a strong ability of overall convergence and high efficiency.
Research on the Simulation Method for I.C.E Structural Acoustic Radiation
Authors: Zhang Bao Cheng , Zhang Guang Jiong , Zheng Bao Qian
Published: March 2010

By systematical research on the analytic procedure of excitation loads inside the internal combustion engine, the computational method of dynamic characteristics and dynamic response, and the prediction technique of structural acoustic radiation, an approach for structural acoustic radiation prediction of I.C.E based on BEM theory, ATV technique and coupled BEM-FEM method is proposed. It is a new and efficient way to solve the problem of engine’s structural acoustic radiation under multi-operating conditions. The numerical simulation results and measured values through experiments indicate that this approach is scientific, correct and feasible.
Research on Numerical Investigation and Test Verification of Brake Performance in a Hydrodynamic Tractor-Retarder Assembly
Authors: Wei Wei , Yan Qing Dong , Wu Jing Yan
Published: March 2010

The brake performance of a hydrodynamic tractor-retarder assembly, which is the combination of torque converter and hyaulic retarder, was studied to explore its work mechanism. Spiral vortex distribution pattern of internal flow field in the assembly was discovered on the basis of reasonable boundary condition, where runaway speed of stator was determined by CFD analysis. Comparison of experimental data and flow field analysis shows that accurate brake performance of hydrodynamic tractor-retarder assembly can be calculated only by 3D flow field analysis presently and numerical simulation results is close to experimental data, and approximate linear relationship exists between runaway speed of stator and rotating speed of pump.
Research on Collision Method for Irregular Mechanism Kinematics Simulation
Authors: Shi Zhi Hui , Ma Xin Lei , Lu Bi Hong
Published: March 2010

General kinematics simulation is only for regular mechanism about turning in fix axis, shifting on plane as well as their compound motions. However, there is no mature technique supporting kinematic simulation for those mechanisms depending on clearance operation such as lorry couplers. Considering such irregularly mechanism, authors proposed a method based on collision kinematics simulation, and combining structure analysis as well as virtual assembly in Pro/Engineer. According to methods above, authors implemented three postures of coupler operation kinematics simulation, as well as the reliability avaluation for anti-creep of coupler function. This method supplies a practical solution for irregular machine kinematics simulation.
Accuracy Synthesis of a 3-PRS Parallel Manipulator Based on Genetic Algorithms
Authors: Sun Tao , Song Yi Min , Xu Liang
Published: March 2010

The existence of the non-compensable errors in limited-degree-of-freedom (limited-DoF) parallel kinematic machines (PKMs) affects the accuracy of mechanism and decreases the location capability. A 3-PRS parallel manipulator as an example, this paper formulates the mathematical model of the accuracy synthesis of the manipulator and carries out the accuracy synthesis based on the genetic algorithms, and then obtains the tolerance range of the non-compensable errors in the manufacture and the assembly.
A Kind of CAD/CAE Integrated Modeling Technology Based on FEATURE
Authors: Li Shen , Shao Xiao Dong , Ge Xiao Bo
Published: March 2010

A kind of CAD/CAE integrated modeling method based on feature is proposed. Firstly, analysis features are attached to CAD model of part and standard part library is formed. Secondly, the CAD model is created using standard parts. Thirdly, geometry information of analysis features is extracted from CAD model and is reconstructed automatically under CAE environment. Finally, based on feature-based meshing and combination technique, CAE model is built quickly. A prototype software for large-scale antenna structure (LSAS) CAD/CAE integrated modeling has been developed and used in performance analysis of a 16-meter-diameter LSAS. The method has been proved to be useful for improving speed, accuracy and consistency of complicated structure CAE modeling notably.
Parameterized Finite Element Analysis for Quick-Opening Supercritical Fluid Extraction Kettle
Authors: Dong Jin Shan , Gu Bo Qin
Published: March 2010

In consideration of the similarities of supercritical fluid extraction (SFE) kettles, the parameterized finite element analysis system was developed based on ANSYS and Visual Basic. The parameterized model building, stress analysis and fatigue analysis for shell, nozzle and quick-opening sealing structure were realized by second development of ANSYS using APDL language. The program which can deal with design parameters was developed based on Visual Basic, and the command stream files, which can be recognized by ANSYS, were modified according to design parameters and sent to ANSYS solver by the program. With the system, the stress and fatigue analysis process for SFE kettle is simplified and the analysis efficiency of SFE kettle is improved.
Research on Virtual Design and Simulation System for Manipulators of Multi-Degree of Freedom
Authors: Zou Hai Xin , Zou Xiang Jun , Chen Yin Le , Sun Quan
Published: March 2010

According to different environment and working requirement, the manipulators with diverse shapes and functions are required. In this paper, a virtual design and simulation system for manipulators of multi-degree of freedom (DOF) was put forward. Knowledge classification and modeling were carried out for the manipulator’s mechanism and motion behaviors. The software architecture framework and platform of the hardware and software were described. The overall program approach and its realization of the system were introduced. Based on the VC++ 6.0 development platform, the manipulator’s design and simulation system was developed and tested by examples. The results show that it provides a theoretical method and a tool for the virtual design and virtual manufacturing of multi-DOF manipulators in complex environment, which elevates the speed and lowers the cost of research and development.
An Analytical Solution to Metal Plane Problem in Terms of Orthotropic Anisotropy and Strain Hardening
Authors: Liu Yao He , Yi Guo Feng , Xiong Jian Ming
Published: March 2010

In this paper, the yield condition of Hill’s orthotropic yield criterion under axial symmetric plane stress state was discussed. The yield function of orthotropic material was proposed and the analytical solution to meet the condition of equations of equilibrium and compatibility under axial symmetric plane stress state is obtained, in which the conditions of power hardening materials was considered. The research result indicates that hardening coefficient and anisotropic parameter have substantial influence over stress and strain. However, in the presence of the coefficient R90=H/F，the influence appears to be quite weak.
Particle Swarm Optimization with Adaptive Inertia Weight and its Application in Optimization Design
Authors: Wang Xiao Lei , Yang Yu , Zeng Qiang , Wang Jin Qiang
Published: March 2010

To avoid the premature convergence caused by basic particle swarm optimization(PSO) in resolving engineering optimization design of highly complex and nonlinear constraints, a new particle swarm optimization algorithm with adaptive inertia weight (AIW-PSO) is proposed. In this algorithm, inertia weight is adaptively changed according to the current evolution speed and aggregation degree of the swarm, which provides the algorithm with dynamic adaptability, enhances the search ability and convergence performance of the algorithm. Moreover, penalty function is used to eliminate the constraints. Finally, the validity of AIW-PSO is verified through an optimization example.
Deformation of Flexspline under Transmission Force in Harmonic Drive
Authors: Chen Xiao Xia , Lin Shu Zhong , Xing Jing Zhong
Published: March 2010

Method to investigate the elastic deformation of a flexspline in harmonic driver was developed under assembly force from wave generator and transmission force. Shell element and tapered beam element were applied to model the flexspline cone and the teeth on the flexspline respectively. Forced displacement of the flexspline in assembly state was imposed by contact analysis between the flexspline and wave generator. According to experimental distribution of tangential forces in transmission state, applying forces at the teeth tips on the flexspline in mesh state, deformation distribution under transmission torque loading was obtained. Simulations of assembly state and transmission state were realized in ANSYS software. In three sections of tooth ring vertical to the axis, the deformation distributions of the flexspline under specified displacement in assembly state were compared with the theory results. Deformation between tip of tooth and neutral layer in assembly state and in transmission state were compared respectively. The deformation results agreed well with the theory results in assembly state, while difference was found in tangential displacement on tooth tips in transmission state, which may influence mesh property evidently under transmission loading.
Key Technology Research on Mould Heating System of Injecting Machine
Authors: Li Jin Guo , Kang Lin
Published: March 2010

Effective calculated method of temperature field analysis was studied on the hot plate by CAE technologies. It provides design method and heating process for the mold. According to the specificity of hot plate, reasonable location of the thermocouple is discussed, power distribution and layout are designed, heating process of the hot plate is studied, so that hot plate temperature reaches the specified temperature and distributes. Feasible scheme has been got by computer simulation and the result is verified by experiment. The two problems of the temperature control precision and surface thermal field has been solved.
Decomposition-Based Modularity Method for Product Collaborative Design
Authors: Liu Jin Fei , Chen Ming , Yao Yuan , Kong Qing Hua
Published: March 2010

With the development of economic globalization, the union enterprises under the circumstance of inter-industry, inter-regional, inter-national have been making rapid development, which requires that the products R & D need implementing in the distributed heterogeneous environment. Modularity is the foundation of product collaborative design (PCD), and the decomposed modules are vital to improve the efficiency and performance of PCD. To meet the modularity requirements of PCD in the distributed heterogeneous environment, a new method of decomposition-based modularity for PCD is presented based on the combination of the heuristic analysis and the quantitative optimization. Firstly, on the basis of the incidence matrix of sub-task, the mathematic model based on multi-objective optimization is established in order to maximize the module cohesion degree and minimize the module coupling degree, while considering the module executable degree as the restrictions. Secondly, the mathematic model is optimized and simulated by the modified PSO, and the optimized modules are obtained. Finally, the rationality and effectiveness of this methodology is proved in an instance of collaborative design related to automobile body.
Multi-Objective Optimization Design of Mold Platens on Large Precision Injection Molding Machines
Authors: Ling Zheng Qi , Wang Jin , Lu Guo Dong , Chen Jian
Published: March 2010

Mold platens play an important role in the injection process of injection molding machines. In this paper, a method of integrating NCGA with FEA is proposed to solve MOP of mold platens on large precision injection molding machines. A Pareto optimum is obtained as the result of the MOP analysis, from which proper solutions can be selected according to diverse design needs. Analytical results indicate NCGA is effective in solving MOP of mold platens.
A New Computer Aided Design System of Belt Conveyor
Authors: He Qing , Dong Da Qian , He Zi Rui , Ju Jing Jie
Published: March 2010

Application technology of computer-aided design to large-scale long belt conveyor is presented. A new software system of belt conveyor design based on the standard CEMA has been developed in which the object-oriented technology and new optimal design method with the standard CEMA were adapted. The profile and operation of belt conveyor can be modeled on real-time by means of visual dynamic components and efficient database management. It is proved that the system is available in design, convenient in operation, rapid in optimization, efficient in calculation, and visual in modeling.
Numerical Simulation on the Airflow of Electric Cutting Tool
Authors: Zhang Qiao Fang , Zhou Ke , Wang Ming Huan , Peng Wei
Published: March 2010

The numerical simulation and experiment had been applied to study the cooling of electric cutting tool. Temperature and wind velocity vector of three-dimensional cooling duct were obtained by Fluent. From the numerical simulation, the stagnation flow, reflow and backset which resulted in the poor cooling condition of the electric cutting tool were discussed. By modifying ribs, partition and outlet, a new cooling duct was reconstructed. The cooling effect of the new cooling duct was better than the original one by the experiment test.
Key Technology and Development on Side Pattern CAD/CAM on Mould for Auto Lamp
Authors: Chen Ze Zhong , Fan Kai , Lou Zhen Liang
Published: March 2010

A model of side pattern CAD/CAM on mould for auto lamp integrated with CATIA V5 is built. After analyzing the properties of design and the manufacture of side pattern on mould for auto lamp, key technology, such as grouping, sorting, determination of continuity, fairing and fitting of side pattern curves, generating of NC files and G codes, are presented. Using out-process redeveloping tools of CATIA V5, a CATIA V5 integrated side pattern CAD/CAM system for mould of auto lamp is developed. At last, a practical example shows that the technology and the software satisfy the design and manufacture of side pattern on mould for auto lamp. The technology and the software have been used in related enterprise successfully.
A Novel Discovery Technique on Attribute Weight of Engine CBR Design System
Authors: Yan Wei , Gao Qi , Liu Zheng Gang , Zhang Shan Hui , Hu Yu Ping
Published: March 2010

An improved multi-group self-adaptive evolutionary programming Algorithm is used to get adapt attribute weight for CBR system. Firstly, this paper analyses the adaptability function based on reference case base REF and testing case base TEST, develops a novel Bi-group self-adaptive evolutionary programming that overcome the lack of conventional evolutionary programming. In this Novel algorithm, evolution of Cauchy operator and Gauss operator are parallel performed with different mutation strategies, and the Gauss operator owns the ability of self-adaptation according to the variation of adaptability function. Information is exchanged when sub-groups are reorganized. Experiment results prove the validity of self-adaptive Algorithm and CBR design system is used successfully in engine design process.
Factors Effect on Vortex Torque of Aerostatic Bearings
Authors: Liu Jing Shi , Sun Ya Zhou , Lu Li Hua , Liang Ying Chun
Published: March 2010

In order to improve the drift accuracy of aerostatic bearings, the air supply pressure and manufacturing errors effect on vortex torque of aerostatic bearings were studied by using the finite element method. This paper analyzed the influence of air supply pressure on vortex torque, in view of elliptical error, incline error of throttle slit and radial eccentricity ratio exist. The quadratic regression orthogonal design was adopted to establish function expression of vortex torque among air supply pressure, elliptical error, incline error of throttle slit and radial eccentricity ratio. In research, the simulation vortex torque values of a certain aerostatic bearing are compared with the experimental values. The predicted characteristics are in good agreement with experimental results and then prove that the finite element model, the method used to solve the problem and the function expression obtained are correct. The research has great significance for predicting performance and choosing the air supply pressure of aerostatic bearings.
Phase-Field Simulation of Three-Dimensional Dendritic Growth
Authors: Zhu Chang Sheng , Wang Jun Wei
Published: March 2010

Based on a thin interface limit 3D phase-field model by coupled the anisotropy of interfacial energy and self-designed AADCR to improve on the computational methods for solving phase-field, 3D dendritic growth in pure undercooled melt is implemented successfully. The simulation authentically recreated the 3D dendritic morphological fromation, and receives the dendritic growth rule being consistent with crystallization mechanism. An example indicates that AADCR can decreased 70% computational time compared with not using algorithms for a 3D domain of size 300×300×300 grids, at the same time, the accelerated algorithms’ computed precision is higher and the redundancy is small, therefore, the accelerated method is really an effective method.
Influence of Laser Parameters on Precision in Hybrid Plasma Laser Deposition Manufacturing
Authors: Qian Ying Ping , Huang Ju Hua , Zhang Hai Ou
Published: March 2010

The present study is a continuation of the previous research on direct metal component fabrication by hybrid plasma and laser deposition manufacturing (PLDM). The overall performance of component depends not only on the plasma but also on the laser. The purpose of this paper is to study the influence of laser parameters, such as average power, repetition frequency and pulse width, on the precision of single layer and analyze the influence rule. The results of this research are presented as follows: (1) The width of single layer decreases with the enhancing of average power and the thickness increases with the enhancing of average power. (2) The width of single layer minishes with the increasing of repetition frequency until it reaches a minimum value, and the thickness increases with the increasing of repetition frequency until it reaches a maximum value. (3) The width of single layer decreases with the increasing of pulse width and the thickness increases with the increasing of pulse width.
Numerical Simulation on 3D Residual Stress Field of Both-Side Laser Shot Peened Specimen with Center-Hole
Authors: Yang X.D. , Zhou Jian Zhong , Huang Shu , Hu Ling Ling , Wang Cheng Dong
Published: March 2010

A numerical analytical model for both-side laser shot peening (LSP) of specimen with center-hole was established, the influence of the center-hole on peening effect was investigated, and the 3D residual stress distributions of ZK60 specimen after one-side and both-side LSP were analyzed. The results showed that compressive residual stresses were obtained at the both sides of specimen after both-side LSP, with a stress value of -179.41MPa on the bottom surface, much larger than that of one-side LSP. The typical experiment of LSP for ZK60 specimen was carried out and the experimental data were well correlated with the simulated results.
A Powder Shrinkage Model for Describing Real Layer Thickness during Selective Laser Melting Process
Authors: Zhang Dan Qing , Cai Qi Zhou , Liu Jin Hui , Li Rui Di
Published: March 2010

Shrinkage tends to generate when loose metal powder melted in each processing layer along the direction of layer growing during selective laser melting process, resulting in an increased real layer thickness. The shrinkage model for layer shrinkage in SLM process is established. The variation of real layer thickness and the relevant mathematical explanations are discussed in this paper. The results show that the total shrinkage of metal powder layer sharply increases in the initial layers, and then reaches to a plateau value with the increased processing layers. This value is defined by the ratio of sliced layer thickness (h) to relative density (k) during selective laser melting process.
Study on the Factors Influencing the Layer Precision in Hybrid Plasma-Laser Deposition Manufacturing
Authors: Qian Ying Ping , Huang Ju Hua , Zhang Hai Ou
Published: March 2010

The present study is a continuation of the previous research on direct metal part fabrication with hybrid plasma-laser deposition manufacturing (PLDM). It is remarkably important for manufacturing high accurate part to investigate the factors influencing the precision of deposited layer and obtain the influence rules. Many factors perhaps affect the layer precision, such as average power of laser, repetition frequency, pulse width, hybrid angle between laser beam and plasma beam, speed of powder feed, deposition speed, and amount of feed along Z direction and so on. In this paper, the factors except laser parameters published in other paper were researched experimentally. The results were concluded as follows: (1) The width of the layer increases and the thickness decreases with the increasing of hybrid angle. (2) The depth of layer increases with the increasing of the amount of powder feed but the width of layer is nearly unchanged. (3) The width and thickness of layer reduces with the increasing of deposition speed. (4) The deviation between the amount of feed along Z direction and the depth of depositing layer makes the part precision decrease.
Analysis of 7050 Aluminum Alloy Crack Growth by Laser Shock Processing
Authors: Ren Xu Dong , Zhang T. , Zhang Yong Kang , Jiang Da Wei , Chen Kang Min
Published: March 2010

Cracks were prefabricated on compact tension specimen of 7050 Aluminum alloy, which was laser shock processing(LSP) once and three times. The whole crack initiation process, distribution and size evolution on aluminum alloy was studied with replica technique and through optical microscope. It was found that without LSP, small cracks initiated at the grain boundary and grew quickly. The cracks continued growing in depth. The growth of short cracks had the trend of stop-and-go oscillation, the crack data were relatively scattered, and short cracks had short average length and grew earlier. After LSP, surface residual compressive stress restrained to the trend of crack origins where crack origins would form most easily; after origination, cracks initiated towards the processed region, but stop temporarily if encountering great resistance, and might generate additional crack origins; Moreover, the higher the level of stress created by LSP was, the fewer cracks initiated.
Synthesis of Intermetallic Ni3Al Alloy: Properties and High Temperature Oxidation Behaviour
Authors: Ismail Roslina , Yaacob Iskandar Idris
Published: March 2010

Two different methods were utilized to synthesize intermetallic nickel aluminide alloy. The first method was combination of powder metallurgy and reaction synthesis (IMC_RS) and the second method was plasma melting to form homogenous plasma melted samples (IMC_PM). XRD patterns for both samples showed complete formation of single phase Ni3Al. Saturation magnetization value for IMC_RS was 0.445 emu/g and IMC_PM was 0.157 emu/g. This was comparable with Ms value of commercial Ni3Al from Alfa Aeser (0.398 emu/g). The reduced elastic modulus, Er value of IMC_PM and IMC_RS were 441.09 MPa. 408.2 MPa respectively. Both samples were exposed to 1%SO2/air gas mixture at 1000oC for 24-hour duration. The isothermal kinetic results for both samples were parabolic indicating rate limiting step. The oxide scales consisted of NiO, NiAl2O4 and Al2O3.
Analysis on Microstructure of Laser Brazing Diamond Grits with a Ni-Based Filler Alloy
Authors: Yang Zhi Bo , Xu Jiu Hua , Liu Ai Ju
Published: March 2010

Brazing diamond grits onto steel substrate using a Ni-based filler alloy was carried out via laser beam in an argon atmosphere. The microstructure of the interfacial region among the Diamond grits and the filler layer were investigated by means of scanning electron microscopes (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS). Meanwhile, the formation mechanism of carbide layers was discussed. All the results indicated that the active element chromium in the Ni-based alloy concentrated preferentially to the surface of the grits to form a chromium-rich layer, and the hard joint between the alloy and the steel substrate is established through a cross-diffusion of iron and Ni-based alloy through parameters optimization.
Linear Friction and Electron Beam Welded Joints of Ti2AlNb/TC11
Authors: Tan Li Jun , Yao Ze Kun , Qin Chun , Guo Hong Zhen , Li Shi Qiong
Published: March 2010

Dissimilar joining of Ti-22Al-25Nb alloy and an α+β titanium alloy TC11 were carried out using electron beam process and linear friction process, respectively. The microstructure and tensile properties of the joints were investigated. The results show that both EBW and LFW could be adopted to the dissimilar joining of Ti-22Al-25Nb/TC11. The EB welded joint exhibits higher strength than that of the LF welded joint, due to the precipitation of O phase in the fusion zone of the former one. These results can be expected to be of great technical interest as basic data for the use of EBW or LFW in aerospace industry.
Bond Thickness Effects upon Dynamic Behaviour in Adhesive Joints
Authors: He Xiao Cong
Published: March 2010

The influence of adhesive layer thickness on the dynamic behaviour of the single-lap adhesive joints is investigated in this paper. The ABAQUS finite element analysis (FEA) software was used to predict the frequency response functions (FRFs) of the single-lap adhesive joints of different thickness of the adhesive layer. As a reference, the FRFs of a cantilevered beam without joint were investigated as well. It is clear that the FRFs of the four beams are close to each other within the frequency range 0~1000 Hz. It is also found that the composite damping of the single-lap adhesive joint increases as the thickness of the adhesive layer increases.
Microscopic Study on the Mechanism of Ultrasonic Nanowelding
Authors: Liu Xuan , Zhao Li Jie , Zhou Hua
Published: March 2010

Using molecular dynamics method, the progress of bonding single-wall carbon nanotubes and metal electrodes by ultrasonic nanowelding technique is described completely at atomistic length scales. The temperature distribution in electrodes is analyzed. The maximal temperature of electrode atoms is about 570.1K. The mechanism responsible for ultrasonic nanowelding is revealed as the result of the high-frequency ultrasonic energy softening the metal and causing plastic deformation of the metal under the clamping stress because of the ‘acoustic softening effect’. The ultrasonic parameter is optimized, which is important in improving the performance of carbon nanotube field-effect transistors and building reliable nanodevices.