bluuebunny/crossref_metadata_2025 huggingface dataset:
Laser Alloying of Multi-Carbides Reinforced Metal Matrix Coating on a Ductile Iron
Authors: Wang Wen Yan , Dong Xiao Ming , Xie Jing Pei
Published: November 2010

A ductile iron coated with metal-matrix pastes containing hard phase TiC and CrxCy was laser alloyed by an Nd: YAG laser and a CO2 laser. The microstructure, composition and wear resistance were analyzed by scanning electron microscopy (SEM), incorporating energy dispersive spectrum (EDS), X-ray diffraction analysis (XRD) and friction wear tester respectively. Results revealed that the alloyed area was composed by alloyed zone and heat affected zone. The microstructure of the alloyed layer was significantly influenced by the laser beam kind. Finer grains and fewer cementites were contained in the alloyed layer produced by Nd: YAG laser. Friction and wear experiments showed that the alloyed layer had better tribology properties.
Research on Micromachined Gyroscope with Electrostatic Drive and Meso-Piezoresistive Detection
Authors: Shi Yun Bo , Wang Rui Rong , Du Kang , Liu Jun
Published: November 2010

In this paper, the structure design and operating principle is introduced to micromachined gyroscope with electrostatic drive and piezoresistive detection. In the paper, the piezoresistive effect of multi-barrier nano-film is used as detection method, which achieves high piezoresistive sensitivity compared with Silicon piezoresistive device. The gyroscope structure and multi-barrier nano-film device is fabricated by using heteroepitaxy GaAs film on Si substrate which implements the process compatible. The natural frequencies of gyroscope are determined from the modal analysis.
Growing Model of Interfacial Layer between Alloy Layer and Matrix in Diffusion Process of Hot Dip Aluminized Steel
Authors: Zhang Wei , Fang Shi Jie , Li Long Xing
Published: November 2010

Intermetallic compounds layer will be formed at the interfaces between alloy layer and matrix in the diffusion process of hot dip aluminized steel, which is beneficial to enhance the binding ability of alloy layer with matrix. However, when the thickness of intermetallic compounds exceeds the certain value, the vast extending force of interfacial void will cause the crack of intermetallic compounds and greatly weaken the spall resistance of aluminized layer. Therefore it is very important for the applications of hot dip aluminized steel to research and control the formation of intermetallic compounds at the interfaces. According to the characteristics of diffusion process of hot dip aluminized steel, the growing model of intermetallic compounds were established in the paper. The computed results were in accord with the experimental value. It can provide reference to the choice of the diffusion parameters of hot dip aluminized steel.
Research on Laser Polishing of Optical Glass
Authors: Kang Gui Wen
Published: November 2010

With the development of photoelectron technology, optical glass and glass ceramic has been used in many different fields. The final machining of this kind of material has very important effect to its future application. In the present study, optical glass and glass ceramic is finished using laser polishing. Laser polishing could eliminate subsurface damage, smooth micro roughness. In certain cases a preheating system should be needed to increase optical glass’ surface integrity. The result shows that laser polishing of optical glass and glass ceramic has higher efficiency compared to conventional optical machining. The flexibility of laser polishing makes it ideal as an enabling technology for the final manufacturing of optical glass and glass ceramic.
Multi-Objective Optimization for High Strength Steel Sheet Metal Forming Process Based on Response Surface Methodology
Authors: An Zhi Guo , Zhang Yu
Published: November 2010

In sheet metal forming process, the input process parameters scatter and considerably result in unreliablity in practical production. Optimization for sheet metal forming process is often considered as a multi-objective problem. An optimizition strategy for high strength steel (HSS) sheet metal forming process was suggested based on response surface methodology (RSM). Latin Hypercube Sampling (LHS) method was introduced to design the rational experimental samples; the objective function was defined based on cracking factor wrinkle factor and severe thinning factor; the accurate response surface for sheet metal forming problem was built by Least Square Method; Multi-objective Genetic Algorithm(MOGA) was adoped in optimization and Pareto solution was selected. The strategy was applied to analyze a HSS auto-part, the result has proved this method suitable for optimization design of HSS sheet metal forming process.
Microstructures and Properties of Co-Based Alloy Surfacing Layer with Longitudinal Magnetic Field
Authors: Su Yun Hai , Liu Zheng Jun , Su Ming
Published: November 2010

In order to systematically study the influence of surfacing current and magnetic field current on hardness and wear resistance of surfacing layer, longitudinal DC magnetic field was applied during plasma arc surfacing Co-based alloy on low-carbon steel. The hardness, wear resistance, microstructure and phase constitution of the surfacing layer were investigated through the tests of hardness, wear, SEM and XRD analysis. The results show that the surfacing current and magnetic field current must be matched properly to achieve the optimal properties of surfacing layer. The optimal values are obtained when the surfacing current is 160A and the magnetic field current is 3A, where the hardness is 43.7 HRC and the wear loss is 0.5493g. The proper electromagnetic stirring induced by electromagnetic field can not only refine the microstructure but also improve the hardness and wear resistance of the surfacing layer.
Preparation of SiO2 Film by Sol-Gel
Authors: Zheng Zhan Shen , Yan Pei Qi , Li Rui Jiao
Published: November 2010

In recent years, the hydrophobic and self-cleaning surface has aroused extensive attention due to its special nature such as waterproof, pollution prevention, antioxidant nature, and so on. In this paper, sol-gel was used to prepare the hydrophobic coating on ceramic surface. Ethanol and TEOS were mixed to prepare the sol as 1:1 volume ratio, and the sol would be coated on the ceramic surface treated by some ways. Then the samples were dried in a certain temperature, then calcined. At last the samples were modified with a certain percentage modifier. In this article, three different factors were discussed, such as vacuuming times, modifing time, and calcining temperatures, eventually it is gotten that the optimal experimental conditions are using 20min to vacuum, 1h to modify and 550 to calcine.
Study on Chromium-Free Color Passivation for Zinc Coating Treated with Silicate
Authors: Yang Xiao Ke , Fan Yun Ying , Jiang Ye Hua , Li Zu Lai
Published: November 2010

This paper mainly focuses on how the silicate liquid composition of chromium-free color passivation affects on passivation result, and confirmes the optimum passivation conditions, and uses two zinc plating system of alkaline and acid deposition. Silicate passivation system is compared with hexavalent chromium passivation technology and the results showed that: the appearance and corrosion resistance of passive films formed on zinc coatings plated with alkaline system are better than samples plated with acid system, and have the same corrosion resistanc with hexavalent chromium passivation. The silicate passivation films can keep 200 hours with no white rust in neutral salt spray test.
Effects of Nano-ZrO2 on the Microstructure and Mechanical Properties of Ti(C,N)-Based Cermet Die Materials
Authors: Wang Xing Hai , Xu Chong Hai , Yi Ming Dong , Zhang Hui Fa
Published: November 2010

In recent, the development of new die materials is one of the important topics in the field of die research. In this paper, effects of nano-ZrO2 addition on the microstructure and mechanical properties of Ti(C,N)-based cermets were studied. The newly developed Ti(C,N)-based cermet die materials with different contents of nano-ZrO2 of 0~25wt% were prepared by hot pressing technique under vacuum atmosphere at 1450°C for 30min. Moreover, the microstructure of this Ti(C,N)-based cermet die materials was observed by environmental scanning electron microscope. It indicates that the comprehensive mechanical properties can reach the optimum when the weight percent of the nano-ZrO2 is 10%. The corresponding flexural strength and fracture toughness is 967 MPa and 13.62 MPa•m1/2, respectively which is approximately 65% and 110% higher than that of the cermet without nano-ZrO2 addition. It suggests that the addition of nano-ZrO2 can improve the mechanical properties especially the fracture toughness and flexural strength of Ti(C,N)-based cermet die materials.
Modal and Strength Analysis on a Gearbox Housing
Authors: Dai Rong , Ma Ji Sheng , Zhang Hua Dong
Published: November 2010

A finite element model for the given gearbox has been established based on NASTRAN, which gives the gearbox theoretical modal analysis results. The dynamic loads of the bearings resulted from kinetic analysis is acted on the gearbox housing and the housing stress distribution under the action of dynamic loads is obtained by the calculation of dynamic strength for the housing. The research results provide a valuable reference for the housing design.
Research on Molding for Al2O3Ceramic Substrate and its Processing Technic
Authors: Zhang Zhan Xin , Hu Hong Kui , Wang Feng Ming , Liu Tao
Published: November 2010

By adopting technique for forming colloid to manufacture Al2O3 Ceramic Substrate, the effect of aggregation reaction which is caused by pH value, temperature for shaping, evocating agent and some other factors of slurry has been researched in the processes for shaping Substrate. The result addresses that the substrate with well-proportioned in density, contractibility and over 78MPa intensity is able to be made while the pH is about 9, the temperature is between 60 and 70°, the shaping duration is no more than 30 minutes, in glass mold, and with 120 item undersize α-Al2O3 powder. To dunk the desiccating substrate for 20 minutes, it would gain the good flexibility, moreover, it is able to be cut. After it is desiccated again, it becomes firm again, this kind of characteristic can be repeated numbers of times.
Optimization of Laser Deposited Ni-Based Single Crystal Superalloys Microstructure
Authors: Santos Edson Costa , Kida Katsuyuki , Carroll Phil , Vilar Rui
Published: November 2010

In this paper, results concerning the microstructure of Rene N4 alloy layers produced by laser cladding on oriented CMSX-4 single crystal substrates are presented. The microstructure of the deposits was analyzed in the solidification condition after different temperature/time ageing cycles in order to assess the possibility of improving high temperature strength of laser deposited superalloys. The present work demonstrates that single crystalline deposits of René N4 nickel superalloy can be obtained provided that the deposition direction and the processing parameters are properly selected. The clad layer is perfectly bonded to the substrate and presents no pores or cracks. The deposits grow epitaxially on the substrate, so they inherit its orientation. For laser beam powers and scanning speeds varying between 500 to 800 W and 4 to 12 mm/s, respectively and (001) substrates, the deposited material presents a columnar dendritic structure consisting of arrays of similarly oriented dendrites, separated by subgrain boundaries, forming a single crystal. Heat treatments effective for the dissolution of detrimental phases and for inducing the precipitation of cuboid ’-Ni3Al strengthening phase precipitates in the laser clads were established.
Closed Hot Precision Forging Process of a Bevel Gear with Large Cone Angle
Authors: Ji Dong Sheng , Wang Xin Yun , Deng Lei , Xia Ju Chen
Published: November 2010

The closed hot precision forging process of a bevel gear with large cone angle was studied. According to the structure features of the bevel gear, two types of relief forging processes were proposed. First, simulations based on thermal-mechanical coupling finite element model were performed with Deform3D. Then the corresponding experiments were conducted and the results perfectly matched the simulation results. The advantages and deficiencies of two processes were discussed and a reliable basis for selecting the optimal process was proposed.
A Heat Transfer and Solidification Model of Continuous Cast
Authors: Zhang Qi , Yang La Dao
Published: November 2010

A model of heat transfer and solidification of continuous cast has been established, including boundary conditions in the mold and spray zones. A finite difference method was used for the numerical simulation. The model calculates the shell thickness and temperature distributions of the slab real time. The importance effect of non-linear material properties of specific heat and thermal conductivity as well as phase changes during solidification is treated. The adequacy of model has been proved by industrial and experimental data. The model can be applied to solve some practical problems in continuous cast.
Review of Materials and Process Modeling Techniques for Creep Age Forming
Authors: Zhan Li Hua , Lin Jian Guo , Balint Daniel S.
Published: November 2010

The Creep Age Forming (CAF) technique has been recently developed and used to manufacture aircraft and aerospace panel components with improved mechanical properties, increased shape stability and reduced fabrication cost. Precipitation hardening, stress relaxation and creep phenomena take place synchronously in the forming process. Significant research work has been carried out over the last two decades and the applications have been expanded. This paper reviews the most recent development of materials and process modeling techniques for this new forming process. Some challenges for future modeling investigation about the novel process are also discussed.
3D Numerical Simulation of Electromagnetic Field during Low Frequency Electromagnetic Casting Process
Authors: Wang Xiang Jie , Cui Jian Zhong , Zhang Hai Tao
Published: November 2010

The rules of the distribution of magnetic field were carried out by numerical simulation. The distribution of magnetic field was got, and the effects of current intensity and frequency on the distribution of magnetic field were analyzed by constructing three-dimensional finite element model and using ANSYS software which is a kind of commercial FEM analysis software. The results show that the intensity of magnetic field is proportional to current intensity, magnetic field is mainly localized in the surface region of liquid melt and there is a notable edge effect in the corner.
Properties and Spot Welding Performance of Copper Composite Reinforced with Recycled Tungsten Carbide
Authors: Hussain Zuhailawati , Almanar Indra Putra
Published: November 2010

In this work, properties and spot welding performance of copper matrix composite electrode reinforced with 15 vol% tungsten carbide particulate from inexpensive raw material were investigated. Mixture of copper and recycled tungsten carbide was milled, compacted, sintered and powder forged at different pressures. Higher forging pressure resulted in higher density and electrical conductivity as it accelerates the flow of copper matrix leading to porosity elimination and improves metal-metal contact within the copper matrix by reducing porosity and oxide film. Welding operation showed that composite electrodes with higher density, electrical conductivity and hardness forms larger and stronger spot weld.
Restoration Technology of 30CrMnSiA Steel Parts on Airplane by Electroless Ni-Plating
Authors: Ge Wen Jun , Li Zhao Hua , Lv Qin Yun
Published: November 2010

The feasibility of electroless Ni-plating was explored in order to solve the problem of the restoration of the parts of aircraft made of high strenth steel. The flow and criterion of the restoration technology were were preliminarily investigated. We have measured the hardness, adhesion strength and antiwear performance of the coating. The results show that the electroless Ni-plating process for restoring the scuffed surface of aircraft parts made of high strenth steel has the advantages of simple procedure, easy operationg, and low cost. The coating is well adhered to the substrate and meets with the requirement for performance. In one word, the restoration technology of aircraft parts made of high strenth steel is good for extending.
Ovality Defect Control for Round Casting Based on Mechanical Deformation Analysis
Authors: Han Zhan Guang , Liu Ke , Zhang Jia Quan
Published: November 2010

Deformation of round castings due to thermal and/or mechanical strain may lead to the occurrence of their ovality defects during continuous casting. Presently, ovality defect from thermal deformation have been effectively controlled in actual casting process with the application of more advanced equipments and more sophisticated control strategies. But the control of ovality defect from larger mechanical deformation still cannot satisfy the need of caster design or higher qualified rate of castings. It is shown that excessive hot pressure while strand passes through tension leveler, is the main reason to generate larger mechanical deformation. With consideration of the characteristics of round caster and the requirement of safety production, a theoretical calculated model based on mechanical deformation analysis has been developed in the paper to eliminate ovality defect specially from the over large hot pressure. Calculation analysis suggests that groove design of drive roller and range of round section sizes should be the important consideration for the determination of hot pressure, and there always exists an optimum value for hot pressure when the machine equipments of round caster have been designed and installed. The model can provide a useful guideline for casting engineers to design the groove of drive roller and to determine reasonable safe hot pressure. Reliability of the model analysis has been verified by industrial application on a newly built round caster.
The Casting Process Design and Simulation of the High-Manganese Steel Roller
Authors: Zhi Xiao Hui , Yin Yi Min , Han Yan Jun
Published: November 2010

The casting process design and simulation of a high-manganese steel roller were presented in this paper. The casting process design principle, process parameters, points of attention, and the simulation parameters were introduced. Huazhu CAE was used to simulate the casting process. The STL document used in Huazhu CAE was converted from the 3D moulding of the casting process using the Solidwork software. The simulation results and practical production showed that the casting process can reduce shrinkage defects of the casting. And practical production also showed that the produced rollers, according to the technique, met the quality demands, such as no crack, no misrun, etc, and they were successfully used at the thermal power plant.
Analysis of Sheet Metal Vibration Incremental Forming Mechanism
Authors: Gong Yao Teng , Zhang Zhong Kai , Jiang Zhi Hong
Published: November 2010

As a force being non-homogenous during incremental forming process, sheet metal tended to instability easily, then the deposition, wrinkle and fracture will be appearing concomitantly. If the vibration technique is introduced to the incremental forming process, its deformation mechanism will be changed, and forming quality is improved. Then some force equations are built by force analyzed for a element in local forming contact zone, some solutions of the force equations are obtained. With process parameters, mechanical performance parameters and vibra parameters given, stress curves are got. It is shown from simulation that the sheet metal stress has prominent variation with vibration，and forming-angle condition and frequency-condition should be met with vibration.
The Effect of Microstructure on Unidirectional Chilled Solidification of High Chromium White Cast Iron
Authors: Dong Shyen Yang , Tien Shou Lei
Published: November 2010

This study mainly investigates the characteristics of carbide and the matrix structure of ASTM A532–87 CLASS Ⅲ high-chromium white cast iron under directional solidification. The two components of high-chromium white cast iron were put in a 3-level Furan sand model, which is placed in a cold-water circulation copper model, producing unidirectional chilled solidification. A K-type thermocouple is employed to measure data for solidification temperature with time. The move velocities of the liquidus phase and solidus phase is calculated. The matrix and the growth characteristics of M7C3 carbide are explored. As determined from the experiment, the liquidus temperature gradient GL is 0.45~ 0.9oC/mm, and the solidus temperature gradient Gs is 4.3~6.2oC/mm. Around 300 nm of the primary carbide is formed from the added elemental nickel being less than 0.3 mm from the chilled end and from the nickel-free alloy being less than 5 mm from the chilled end. As the distance from the chilled end increases, the primary carbide gradually becomes coarser, and the distance between eutectic carbide groups is increased. This study employs EPMA to analyze the changes of primary carbide, eutectic carbide and matrix components with distance from the chilled end, as well as changes in the distributions of chemical elements.
Optimization and Analysis of Chemical Sensor Structure for Food Hazard Detection
Authors: Zhao Fu , Wang Ping , Gong Yan Jue , Zhang Li , Meng Chun Ling
Published: November 2010

The structure of chemical sensor has great influence on the performance of the sensor. This article presents an optimum design method to improve dynamic stiffness of the sensor structure. The original resonance frequency and modes shape of the structure are obtained by the finite element analysis. Then a series of reasonable parameters are determined by optimum calculation. In the end, the result of the random vibration analysis verifies that the performance of chemical sensor structure for food hazard detection is improved greatly by the presented method here.
Influence of Welding Parameters on Residual Stress in 9% Ni Steel for Low Temperature Service
Authors: Yan Chun Yan , Li Wu Shen , Bai Shi Wu
Published: November 2010

Based on welding heat transfer theory, heat elastoplasticity theory and phase transformation theory, welding residual stress in multi-layer welded joint of 9% Ni steel for liquefied natural gas (LNG) storage tanks was simulated using SYSWELD finite element analysis software. Taking into account nonlinear relationships between temperature and mechanical properties, together with influence of transformation latent heat on temperature field, double ellipsoid heat source model was applied in the simulation of the three fields (temperature field, microstructure field and stress-strain field). Distribution pattern of welding residual stress in 9%Ni steel welded joint was obtained through numerical simulation. Results showed that heat affected zone (HAZ) showing high-level residual stress was the main stress concentrated part of the welded joint. Longitudinal residual stress appeared to be tensile in the weld and HAZ, and compressive in regions remote from the weld. A match of low heat input and high interpass temperature should be employed to lower residual stress level in HAZ. Simulation results were well consistent with theoretical analysis.
Study on Morphologies of PAM Films
Authors: Lee Maw Tien , Wu Wei Ting
Published: November 2010

Research in polymer gel is very popular recently, for instance, polyacrylamide (PAM). PAM gels are well-known for their highly water-absorbent properties. They are usually used as thickeners, suspending agents, soil erosion control reagents etc. In this study we investigated effects of the pH value of PAM solution and the charge density of PAM on morphologies of PAM films. Morphologies of PAM films adsorbed onto the glass surface were obtained with an atomic force microscope (AFM). The experimental results indicated that morphologies of PAM films might vary strongly with acidities of PAM solutions. The base-treated PAM formed tassel-like patterns, the acid-treated PAM existed as grains of various sizes, and the as-received PAM had uniform small ball-like shape. A film flow model was used to explain the experimental results.
Optimization of Multi-Response Problems Using Taguchi's Quality Loss Function Based on Grey Relational Grade
Authors: Ku Wei Liang , Chow Han Ming , Lin Jiang Long , Wu Kun Ling , Sheu Tsong Shin
Published: November 2010

This article presents an approach which first combines grey relational grade and weighted quality loss function to convert the values of multiple responses obtained from each of the Taguchi orthogonal designed experiments into a single performance evaluation value. Then the analysis of variance (ANOVA) and the SN ratio based Taguchi analysis are conducted to find out respectively the relative importance of the process parameters and a set of near optimal parameter settings. A validation experiment is then conducted to confirm the finding. A case of multi-response turning process optimization is used to illustrate the proposed approach. Two sets of weights for the total quality loss were applied and the results were compared. The effectiveness of this approach was demonstrated by the improvement of turning performance in the both weight settings.
Effect of Working Pressure on Microstructure and Mechanical Properties of Magnetron Sputtered ZrN Coatings
Authors: Qi Zheng Bing , Sun Peng , Zhu Fang Ping , Huang Ruo Xuan , Wang Zhou Cheng , Peng Dong Liang , Wu Chong Hu
Published: November 2010

The influence of working pressure on microstructure and mechanical properties of magnetron sputtered ZrN coatings were systemically investigated. The results reveal that a decreased working pressure results in preferred orientation evolution from (111) to (200) and cross-sectional morphologies transition from columnar structure to equiaxed grains. These microstructural changes are considered responsible for an increase in hardness and modulus with decreasing working pressure. Chip spallation and plastic deformation failure modes are observed during scratch testing, and the increased critical loads are attributed to higher hardness and elastic modulus, as well as moderate compressive stress at lower working pressure.
Through Silicon Vias (TSVs) Technology for MEMS Packaging
Authors: Pan Kai Lin , Liu Jing , Wang Jiao Pin , Huang Jing
Published: November 2010

Through silicon vias (TSVs) provide advanced vertical interconnections solutions for system-in-package (SiP) (such as chip to chip, chip to wafer, and wafer to wafer stacking), wafer-level packaging, interposer packaging. At present the shortest electrical path (vertical electrical feed through) between two sides of a silicon chip is one of the important applications. In order to achieve high density and high performance package, TSVs technology has been developed. And for three-dimensional (3D) MEMS (Microelectromechanical System) packaging, TSVs are the most important enabling technology. In this paper, some advantages of TSVs technology are described, and process flow of TSVs module is introduced firstly. Subsequently, a novel electricity test method of Non-Ideal Planes for TSVs is introduced. Finally, many critical issues and challenges of TSVs are reviewed.
The Influence of Surface Texture on Rolling-Contact Fatigue of PEEK Bearings in Water
Authors: Honda Takashi , Kida Katsuyuki , Santos Edson Costa , Kashima Yuji
Published: November 2010

The effect of machining conditions on the rolling contact fatigue (RCF) strength of PEEK polymer bearings was investigated. RCF tests were carried out by using bearings machined by different conditions. The surface profile and roughness were observed before and after testing by laser confocal microscope. Pitting and cracking were associated with the different initial surface conditions. From the obtained results, we found that the RCF strength of machined surfaces decreases when the surface becomes rougher.
Optimization of Thermal Friction Drilling Using Grey Relational Analysis
Authors: Ku Wei Liang , Chow Han Ming , Lin Yao Jang , Wang Der An , Yang Lieh Dai
Published: November 2010

The main purpose of this research is to study the optimal machining parameters for a novel process of thermal friction drilling on SUS 304 stainless steel. The experiments were conducted according to an L9 orthogonal array based on Taguchi experimental designs method, and the multiple performance characteristics correlated with surface roughness (SR) and bush length (BL) was investigated by grey relational analysis systematically and comprehensively. Moreover, the significant machining parameters that most intensively affected the multiple performance characteristic and the optimal combination levels of machining parameters associated with the thermal friction drilling on SUS 304 stainless steel were determined through the analysis of variance (ANOVA) and the response graph of grey relational grade. The main machining parameters of the thermal friction drilling such as friction angle, friction contact area ratio, feed rate, and drilling speed were selected to evaluate the effects on SR and BL. The experimental results show that the thermal friction drilling revealed beneficial effects on SR and BL for drilling processes. Moreover, the optimal machining parameters for multiple performance characteristics associated with SR and BL were attained. The developed thermal friction drilling avoids serious tool wears, enhances the surface quality of the machined hole, and prolongs the tool life significantly.
Study on Optimization and FEM Analysis of Centrifugal Pump Body Structure
Authors: Wu Lan Ying , Wang Yan Lin
Published: November 2010

The centrifugal pump is the common mechanical equipment, which is extensively applied in the water conservancy, ships and other projects. In this paper, the centrifugal pump body structure was analyzed based on the actual working conditions, and the structure was also optimized. The research results show that the maximum equivalent stress of pump body structure is in the tongue, when the grid cell size is 6mm, the maximum equivalent stress is 36.843MPa; The maximum equivalent stress increases as the grid cell size decreases, and the unit number increases rapidly as the grid cell size decreases; When the wall thickness of pump is selected appropriately, the material can be saved about 6%, and the optimized structure of pump can be also meet the structural performance requirements.
Friction and Flow Behavior of Ceramics in Ring-Compression Test
Authors: Wang Hui Gai , Wang Fei , Song Yan Pei , Zhang Kai Feng
Published: November 2010

Float polishing is one of the advanced ultra-smooth surface polishing techniques. Mechanical structure and polishing principle of float polishing are introduced. Polishing experiment about polishing ultra-smooth surface of GCr15 rectangular workpiece is performed by the CJY500 ultra-precision polishing machine, experimental results show that float polishing should be achieved metal nanometer level surface without degenerating layer. The application scope of float polishing is extended, the application has significant reference value for polishing ultra-smooth surface of metal workpiece.
Study on Float Polishing of Metal Nanometer Surface
Authors: Chi Xian , Suo Xiao Hong
Published: November 2010

Float polishing is one of the advanced ultra-smooth surface polishing techniques. Mechanical structure and polishing principle of float polishing are introduced. Polishing experiment about polishing ultra-smooth surface of GCr15 rectangular workpiece is performed by the CJY500 ultra-precision polishing machine, experimental results show that float polishing should be achieved metal nanometer level surface without degenerating layer. The application scope of float polishing is extended, the application has significant reference value for polishing ultra-smooth surface of metal workpiece.
The Casting Process Design and Simulation of the Large-Scale Volute of Dredge Pump
Authors: Zhi Xiao Hui , Yin Yi Min , Han Yan Jun
Published: November 2010

The casting process design and simulation of the large-scale volute of dredge pump were presented in this paper. The casting process design principle, process parameters, points of attention, and the simulation parameters were introduced. Huazhu CAE was used to simulate the casting process. The STL document used in Huazhu CAE was converted from the 3D moulding of the casting process using the Solidwork software. The simulation results and practical production showed that the casting process can reduce shrinkage defects of the casting.
Quantitative Analysis for Micro Geometrical Characteristic of Rough Surface Profile Based on Fractal Theory
Authors: Yang Xiu Juan , Xu Zhi Qian , Yan Xiang Zhen
Published: November 2010

In this paper, a quantitative analysis for the micro geometrical characteristic of rough surface profile is researched with the fractal theory. Firstly, the fractal dimensions of profile curves under different surface roughness are obtained by using the vertical section method, and then the theoretical relationship between the surface roughness and the fractal dimension is built. Secondly, according to the surface profile curve composed of many triangle peaks, the angles and heights of them are calculated to study the micro geometrical size. Through their variation laws changing with the fractal parameters, the calculation formulas of their average values related to fractal dimension are obtained by using mathematics regression tools. Finally, combing three theoretical relationships built above, the geometrical characteristic of the rough surface profile can be calculated with the surface roughness and accuracy requirement known.
Linear Friction Welding Performance of Hydrogenated Ti-6Al-4V Alloy
Authors: Liu Peng Tao , Zhao Xiu Juan , Zhang Tian Cang , Hou Hong Liang , Chen Chun Huan , Ren Rui Ming
Published: November 2010

The linear friction welding (LFW) performance of hydrogenated Ti-6Al-4V alloy was investigated. The effects of hydrogen on macro-features and axial shortening as well as microstructure of Ti-6Al-4V alloy joints welded by LFW were analyzed. The mechanical properties of joints after dehydrogenation were also examined by tensile test at room temperature. The results indicated that the hydrogenated Ti-6Al-4V specimens containing 0.3~0.4 wt% hydrogen had a better microstructure and plastic deformation ability, which resulted in the optimum welding performance improvement of LFW. The critical power input of LFW could be lowered by addition of hydrogen to Ti-6Al-4V alloy. The results of tensile test showed that joints which experienced thermohydrogen processing possessed the same tensile strength and plasticity as original joints.
Research of Self-Learning of Plate Deformation Resistance Based on Genetic Algorithm
Authors: He Chun Yu , Jiao Zhi Jie , Wu Di
Published: November 2010

The model parameters value of deformation resistance determines the prediction accuracy of rolling force model during the plate rolling. According to the influencing factors analysis of rolling force calculation error, the genetic algorithm was introduced into the self-learning method of deformation resistance, and searches the optimal value of deformation resistance on the basic of space exploration and optimization ability of genetic algorithm. The decision variable selection, the coding and decoding, the fitness evaluation and the terminal conditions process were implemented during development process of self-learning system. The results show that the optimization speed and accuracy can meet production requirement.
Research on the High-Efficiency and Energy-Saving Cutting of the Aero Engine Fan Blades
Authors: Xu Li , He Geng Huang , Cai Zhao Hui , Jia Dong Kai , Wang Zhen Bo
Published: November 2010

As the heart of the aircraft, aircraft engine is the decisive factors of aircraft performance. The turbofan engine technology is in the forward position of aero engine, and has become the main power of fighter and civil aircraft. In order to improve the processing efficiency of the aero engine fan blades, a high-efficiency and energy-saving technology was given to replace the traditional processing methods. The paper analyzed and researched the problems which appeared in the machining process of the aero-engine, and the high-efficiency and energy-saving methods was summarized which would become the technical guidance of high efficiency machining of the aero engine fan blades.
Analyses of Guiding Force for the Ring Rolling Mill
Authors: Zhao Dong , Xu Zeng Hai , Wang Qiang , Cai Dong Mei
Published: November 2010

The guiding forces will affect the stability of the ring rolling process and the quality of the product directly. In this paper, the guiding forces and the sector gear forces are analyzed by building theoretical equations and numerical value simulations. The variation tendencies of the guiding forces and the sector gear forces changing with the ring’s outer diameter in both steady and unsteady ring rolling phases are found out base on the theoretical and simulation analyses.
Numerical Simulation of Residual Stress and Deformation of Special Resistance Welding of Nuclear Power Zirconium Tube
Authors: Lin Zu Wei , Chen Fang Quan , Liang Guo Wei
Published: November 2010

According to the actual situation of special resistance welding capp of nuclear power zirconium tubes, using nonlinear finite element analysis technology to establish an three-dimensional numerical analysis model. Analysising the distribution rules of welding residual stress and deformation. Simulation results can be explained a number of welding-related stress problems and also provide a favorable reference for optimizing the welding capp method and implementation of capp processes.
Hydraulic Experiments of Mold Filling Process in Horizontal Centrifugal Casting
Authors: Song Nan Nan , Wu Shi Ping , Kang Xiu Hong , Li Dian Zhong
Published: November 2010

Mold filling process in horizontal centrifugal casting was analyzed in this paper. The effects of rotation speed on flow pattern were studied. Results show that the flow pattern changes greatly with increasing rotation speed and the first thread interval shows significant differences within each group. It is found that inappropriate rotation speed results in liquid drop during filling process, leading to casting defects.
A New Non-Sinusoidal Oscillation Waveform for Continuous Casting Mold
Authors: Jin Xin , Ren Ting Zhi
Published: November 2010

A new non-sinusoidal oscillation waveform which is shown by waveform distortional rate was advanced. The amplitude, oscillation frequency, waveform distortional rate and casting velocity were established for a computer model of the continuous casting process. The range of waveform distortional rate was ascertained. The choosing method of amplitude and oscillation frequency was given. These offered a theory basis to the application of the advanced technique. Industrial scale experiments showed the new type waveform is effective on improving the quality of continuous casting slab and reducing breakout.
Realization of Surface Topography Separation by B Spline Wavelet
Authors: Huang Mei Fa , Cheng Xiong , Qian Guang , Huang Jiang Tai , Zhang Jing , Jing Hui
Published: November 2010

With the development of science and technology, the higher and higher surface accuracy of workpiece is required. The characterization of surface topography affect greatly on functional performance of workpiece. In recent years, many researchers have made a large progress on the study of surface topography and presented some related standards. The assessment of parameters of surface roughness, however, has not been researched intensively in the new generation of standards system. This paper proposes a novel roughness separation method based on B spline wavelet to analyze engineering surface. This method improves accuracy of roughness signal separation. The experimental results show that B spline wavelet can extracts accurately the roughness component and experiment results by the proposed method fit with the actual value of the standard sample plate.
Defect Analysis of Cup-Shaped Aluminum Alloy Forgings with Flange
Authors: Dong Hong Bo , Wang Gao Chao
Published: November 2010

Effect of the size and shape of cup shaped forgings with flange on forming capability of aluminum alloy was investigated. The numerical simulation was carried out on the extrusion forming process for each part using two-dimensional elastoplastic finite element method. The metal flow behavior was analyzed, and the forming defects were predicted. Meanwhile, the corresponding experimental researches were conducted. The results show that the forming defects like folding or crack appear in each aluminum alloy forging. The size and shape of cup shaped parts have a great influence on the type and size of forming defects. Good agreement is found between the numerical results and experimental work. The results present important references for technology analysis and mould design.
Study on the Flow Behavior in a Tubular Cavity during Water-Assisted Injection Molding
Authors: Kuang Tang Qing
Published: November 2010

A simulation model for the filling of a tubular cavity during water assisted injection molding is proposed. The polymer melt and water are assumed to be incompressible and to follow a Hele-Shaw fluid behavior. The finite element/finite difference/control volume methods are adopted for numerical simulation of the melt front, pressure at injection location variation, water thickness fraction and bulk temperature about a curved pipe, the simulation results have good agreement with the results presented in the former experiment. In comparison with the simulation result of gas-assisted injection molding, water assisted injection molding can give parts with thinner and more uniform walls and more rapid cooling.
The Cutting Forces in Milling of Ti6Al4V Based on Single Factor Method
Authors: Tian Rong Xin , Yang Zhen Chao , Zhang Ding Hua , Huang Xin Chun , Liang Yong Shou
Published: November 2010

In order to provide theory basis and experimental evidence for optimizing milling parameters, the cutting force prediction models for milling of Ti6Al4V with uncoated cemented carbide tool were built based on single factor method. The significances of the cutting force prediction models were checked. The effects of milling speed, feed per tooth, milling depth and milling width on cutting forces were also studied. The results show that the built prediction models can be applied effectively to predict the cutting forces in milling of Ti6Al4V in the experiment parameters range. Milling depth has highly obvious influence on cutting forces among these milling parameters. The cutting forces decrease with the milling speed increasing, and increase with feed per tooth, milling depth and milling width.
A Machine Vision Approach to Tool Wear Monitoring Based on the Image of Workpiece Surface Texture
Authors: Wang Zhong Ren , Zou Yu Feng , Zhang Fan
Published: November 2010

Machine vision technique is an advanced method for tool wear monitoring. In this article, a holding system has been designed and fabricated to realize the combination of machine tools and machine vision system. On-machine experiments were carried out to test the effect of this method. Experimental results indicate that tool condition monitoring can be successfully accomplished by analyzing texture feature information extracted from the machined surface.
Repairing Surface Fatigue Damage of the Metal Material by Heat Treatment
Authors: Guo Ting Liang , Han Zhao Xing
Published: November 2010

In this paper, using experimental method studied to repair surface fatigue damage of the metal material by heat treatment. Analyzed the mechanism to repair surface fatigue damage of the metal material by heat treatment. From the test, it have been found that the Metal materials has temping threshold behavior in repairing it’s fatigue damage by heat treatment. For the same kind of material, there is a threshold characteristics in choosing tempering temperatures when repaired the fatigue damage of metal material surface through changed tempering temperatures. Experimental results shows that the temping temperature threshold to repair metal material fatigue damage is the first tempering temperature after materials was hardened before it was in fatigue damage.
Temperature Field Numerical Simulation of Laser Welding Joint of Stainless Steel Automobile Vent Pipe
Authors: Liu Li Jun , Di Tie Nan , Zhu Rong Hua
Published: November 2010

Ferrite stainless steel has been widely used in foreign automobile vent pipe. During the production of domestic automobile vent pipe, because the crystal grains of welding Joint heat-affected zone are not refined by heat treatment and become very big, forming properties of cold machining of ferrite stainless steel become bad. In order to optimize welding technology, the temperature field of laser welding joint of stainless steel automobile vent pipe is simulated. The temperature field model of laser welding joint of 409 L stainless steel pipe is built based on the pair heat source model. At the same time, the affecting factors are considered, such as thermal radiation, phase change latent heat, thermophysical properties of materials with temperature changes and the spread of convective heat in the liquid metal in the model. The temperature field in different welding parameters are simulated. The impact of process parameters on the temperature distribution is acquired. The experimental results can help works, such as accurately understanding laser welding thermal process, predictive control of welding stress and deformation, and improving cold forming quality of automobile vent pipe.
Study on Synthesis and Properties of the Hafnium Tungstate by CO2 Laser
Authors: Wang Jun Ping , Chen Qing Dong , Liang Er Jun
Published: November 2010

The crystal structure of hafnium tungstate displays unusual property of isotropic negative thermal expansion in a wide temperature range which brings about a number of important potential applications. In this work, densely packed hafnium tungstate blocks are rapid synthesized by CO2 laser. The result of XRD and Raman spectra show that the samples contain single cubic phase of α-HfW2O8 with space group P213. The SEM observations show that the sample is composed of nano-rods which grow horizontally on the surface and in the interior. The nano-threads in the interior are composed of densely packed nano-crystallites.
Analysis on Microstructure and Properties of Plasma Welding Joint with Surfaced Cobalt - Based Alloy Layer
Authors: Gao Wei , Chen Cong
Published: November 2010

The microstructure and microhardness of plasma welding (PAW) joint with surfacing welded cobalt-based alloy have been investigated by using Optical microscope (OP) ,X-ray, scanning electron microscope (SEM),and microhardness testing. The results show that the surfacing layer microstructure is made up of the dendrite (γ-Co) and eutectic (γ-Co+M7C3). The microhardness decreases from surfacing layer to substrate. The highest hardness on the surfacing layer obtains with 550HV up. The fusion zone’s and substrate’s microhardness is about 380HVand 280HV respectively.