bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic Finite Element Method for Nonlinear Dynamic Problem with Random Parameters
Authors: Wang Qing , Cao Yang
Published: February 2011

Several algorithms were proposed relating to the development of a framework of the perturbation-based stochastic finite element method (PSFEM) for nonlinear dynamic problem with random parameters, for this purpose, based on the stochastic virtual work principle , some algorithms and a framework related to SFEM have been studied. An interpolation method was used to discretize the random fields, which is based on representing the random field in terms of an interpolation rule involving a set of deterministic shape functions. Direct integration Wilson- Method in conjunction with Newton-Raphson scheme was adopted to solve finite element equations. Numerical examples were compared with Monte-Carlo simulation method to show that the approaches proposed herein are accurate and effective for the nonlinear dynamic analysis of structures with random parameters
Oxidation Resistance of CrN and CrAlN Coating Tools
Authors: Liu Ai Hua , Deng Jian Xin , Cui Hai Bing , Zhao Jun , Ai Xing
Published: February 2011

CrN and CrAlN coating tools were heated and heat-preserved in electric stove to make oxidation experiment. The results were obtained through SEM, EDX and XRD. The results are as follows: The oxidation of CrN and CrAlN coating is induced by the micro-holes which were formed by the diffusion of nitrogen atoms and chromium ions towards the coating surface under sufficient thermal energy. With the incorporation of Al, CrAlN coating showed stronger oxidation resistance as compared to CrN. The dense mixture of Cr2O3and Al2O3makes oxygen diffusion through the film difficult and then oxidation and decomposing are alleviated effectively, therefore CrAlN coating can remain high oxidation resistance and high hardness after high temperature which make this coating tool be competent for high speed machining of the hardworking materials. In addition, the failure of the coating is primary induced by oxidation and the different expansion coefficients between coating and substrate.
Surface Roughness Prediction in End Milling of Machinable Glass Ceramic and Optimization by Response Surface Methodology
Authors: Reddy Moola Mohan , Gorin Alexander , Abou El Hossein Khaled A.
Published: February 2011

This paper presents the prediction of a statistically analyzed model for the surface roughness,R_a of end-milled Machinable glass ceramic (MGC). Response Surface Methodology (RSM) is used to construct the models based on 3-factorial Box-Behnken Design (BBD). It is found that cutting speed is the most significant factor contributing to the surface roughness value followed by the depth of cut and feed rate. The surface roughness value decreases for higher cutting speed along with lower feed and depth of cut. Additionally, the process optimization has also been done in terms of material removal rate (MRR) to the model’s response. Ideal combinations of machining parameters are then suggested for common goal to achieve lower surface roughness value and higher MRR.
Press Forging of Thin-Walled AZ31 Magnesium-Alloy Components
Authors: Chen Fuh Kuo , Chen Shin Gee
Published: February 2011

The press forging of AZ31 magnesium-alloy sheets for producing thin-walled structural components used in the electronics industry was examined by both the finite element analysis and the experimental approach in the present study. The experimental results obtained from the compression tests and ring compression tests were employed in the finite element simulations to investigate the effects of process parameters, such as forming temperature, friction condition, embossment location, and sheet thickness on the formation of embossments in a press forging process. The finite element simulation results reveal that a cost-effective press forging process of AZ31 magnesium-alloy requires an optimum combination of the above parameters. The detailed examination of the effects of the process parameters on the formation of embossments made in the present study could provide a design guideline for a press forging process of AZ31 magnesium-alloy sheets.
Thermal Stability Determination, Anti-Biodegradation, and Thermal Degradation of Nitrocellulose with Various Nitrogen Content by DSC and FT-IR
Authors: Chu Yung Chuan , Tsai Fang Chang , Chen Wei Ting , Tsai Lung Chang , Shu Chi Min , Lin Chun Ping
Published: February 2011

This study fully exploited the advantages of the similarities between chitosan and nitrocellulose (NC), their non-toxicity, superior germproof effects, and the characteristic of restraining fungal growth, to prevent NC’s biodegradation. In a comparison between NC’s Ea, the differences among them were dealt with or not with germproof chitosan by differential scanning calorimetry (DSC). We also observed specific functional groups with Fourier transform infrared (FT-IR) spectrometer to characterize the functional group transformation of NC under various thermal conditions.
Phase-Field Simulation of Double Dendritic Growth in Solidification of Binary Alloy with Forced Convection
Authors: Liu Qiang , Yang Xiang Jie , Liu Zhi Ling
Published: February 2011

A phase-field approach which incorporates mass and momentum and solute conservation equations for simulation of Al-Cu binary alloy solidification is studied. The effect of force convection on the double dendrite growth and solute profile during the solidification of binary alloy were investigated. The results indicate that dendritic grows unsymmetrically under a forced flow, the growth velocity of the upstream tip is faster than the downstream tip. The downstream tip of the first dendrite and the upstream tip of the second dendrite are influenced each other, the upstream tip of the second dendrite will Coarsen, and the concentration at the boundary between them is the highest. Moreover, the interaction between the two dendrites is more and more obvious with the increasing of the flow speed.
The Determination of Using Limiting Clearance between Crank Pin and Bearing Bush in Volkswagen
Authors: Yang He Li
Published: February 2011

Nowadays, the workers in automobile service enterprise use their experience to decide the using limiting clearance between crank pin and bearing bush. It is not enough to be scientific and accurate and it has caused waste on the manpower and financial resources. By using the theory of finite element and getting help from the large analysis software ANSYS, this paper calculated the limiting value of fit clearance between the crank pin and bearing bush scientifically which is in some engines belonged to the vehicle types of Volkswagen. Based on calculation, it has been found that the using limiting value of fit clearance between crank pin and bearing bush was generally small. The analysis and calculation in this paper has guiding significance to the development of automobile maintenance trade.
Direct Electro-Magnetic Mechanical Analysis of U-Shape Coil
Authors: Tsai Gwo Chung , Dong Jyun Cian , Cheng Tung Chen , Chu Yu Yi , Fang C.K.
Published: February 2011

This research to carry on the 3D model of electro-magnetic-mechanical forming analysis, its goal is lies in discusses the magnetic force which electric current produces the influence which creates to the plate, like distortion, stress and so on aspects. But before the analysis, establishes the 3D model first, in converges in ANSYS, gives the material parameter, the boundary condition and so on, then carries on the solution, subsequently obtains the analysis result. Knew by the analysis result, in approaches corner on the U shape coil dull position, its amount of deformation is the maximum value, and stress maximum value also in corner.
Optimal Design of Automotive Steering Column Bearing by Simulated Annealing Algorithm
Authors: Yu Sui Ran , Tao Jing
Published: February 2011

The steering column assembly which connects the steering wheel and the steering gear is a very important part of the steering system. This paper presented the optimization design and testing of the steering column upper bearing of an upcoming automobile targeting the 2010-2015 Chinese market. The design problems were formulated into an optimization problem and were solved by Simulated Annealing Algorithm. 6 sample bearings were produced according to the optimization results and tests of steering upper bearing durability, steering shaft looseness and rotation effects performed on each sample to verify the optimized design. According to the test results, the optimal design of the steering column upper bearing is reliable. By using the Simulated Annealing Algorithm, the design time and costs of the steering upper bearing were reduce at least by 2 months and 60,000 USD, respectively.
Temperature Rise and Heat Transfer in High Speed Machining: FEM Modeling and Experimental Validation
Authors: List Gautier , Sutter Guy , Bi Xue Feng , Bouthiche Abdenbi , Arnoux Jean Jacques
Published: February 2011

Numerical and experimental approaches are mutually conducted to investigate the temperature rise in steel machining at high cutting speed. The process is modeled using a fully coupled thermo-mechanical finite element scheme. Cutting tests were carried out at 38 m/s on a ballistic orthogonal cutting set-up equipped with an intensified CCD camera. Analysis of experimental results leads to determine the variables which control heat transfer between the tool and chip. A discussion about the most important parameters controlling the temperature rise at the tool-chip interface is then proposed. The results also show that the temperature-dependence of the frictional stress modeling can improve the accuracy of the numerical simulations.
Influence of Friction on the Vibratory Response of Structure
Authors: Miao Xiao Mei , Huang Xiao Diao
Published: February 2011

Friction is a phenomenon caused by relative motion, which can be used to absorb vibrational energy. The influence of friction on vibration responses of structures is complex due to the complicacy and nonlinear of the friction itself. In this paper, a 3-DOF spring-damper model with/without friction force was studied to expose how the friction governed the vibratory responses. Several popular friction models were reviewed and LuGre Model was used in this paper. The vibration properties under sine excitation and random were simulated by the Matlab Simulink Software. The results showed that friction absorbed vibration well and vibration damping was rapid. The characteristics of friction influence resulted from comprehensive functions of all factors, such as types of excitation, excitation amplitude and frequency and the location of friction.
Bio-Oil Production from Agricultural Residues in Northeast of Thailand by Fast Pyrolysis Technology
Authors: Theansuwan Wasan , Monteepila Montee , Sriprateep Keartisak
Published: February 2011

The aim of this research is to design and fabricate the machine for production of bio-oil from agricultural residues in northeast of Thailand. Experiment: to produce the bio-oil from corn-stalk, husk and sawdust with 200 g/hr of capacity, 500°C of reactor temperature, -10°C of condensing unit temperature and testing of the mechanics and chemical property. The results showed that the yield of bio-oil from corn-stalk husk and sawdust are 17.40 18.40 and 22.40, respectively. According to the physical characterisation of the products, it was found that the bio-oil produced in this work showed similar properties to the bio-oil from commercial production. The results found in this research are useful for the development of a larger-scale bio-oil production unit, which is an on-going project at the Faculty of Engineering, Maha Sarakham University.
Simulation and Design for Laser Protective Structures of Aluminum Material
Authors: Wang Yu Heng , Shu Qing Bang , Du Tai Jiao , Meng Fan Yuan , Yang Xiao Ya , Cai Li Bing
Published: February 2011

There are two protection structures for duralumin sheet, including surface anodizing and spraying ZrO2 coating, designed for preventing damage induced by laser. In this paper, for anodized aluminum sheet and ZrO2 coated sheet, the ability for laser protection has been simulated and analyzed. The thermal model of sandwich material is established and a finite element method (FEM) code is developed. The rule of the thermal effects in two structures induced by laser irradiation have been discussed, under chosen requirements of laser protection, including that laser power density is 500W/cm2; irradiation time is 3s; the aluminum sheets cannot be much thicker than 3mm; reflectivity cannot be much than 0.6. And the calculation results are verified experimentally and can give a guide to design for laser protection.
Numerical Modeling of the Thermal Performance of 3D SiP with TSV
Authors: Pan Kai Lin , Huang Jing , Liu Jing , Zhu Wei Tao , Ren Guo Tao
Published: February 2011

Electronic package development is driven by the continuous increase in demands for miniaturization of products with enhanced performances. Three Dimensional System in Package (3D SiP) has become a key technology to satisfy the request. The 3D SiP with Through Silicon Via (TSV) technology is developed for chip to chip stacking in a package with superior electrical performance than conventional structures. In this study, we evaluate the thermal performance of 3D SiP with TSV technology using Finite Element Method (FEM). The evaluation topics covered impacts of various materials of mold, 3D SiP models with and without TSV, and various convention conditions. The results indicated that the role of TSVs in heat dissipation is not obvious in this study, and the maximum temperature merged in the center of the chip1 under different conditions which are considered.
Numerical Analysis of Thermally-Induced Residual Stresses in Plasma Facing Components for Fusion Reactor
Authors: Sha Jian Jun , Hao Xu Nuan , Wang Jing , Gao Xiao Wei
Published: February 2011

The realization of a fusion reactor is critically dependent on the successful development of high performance materials. Especially, the plasma facing components (PFCs) which basically consist of a direct plasma facing armor material and a heat sinking material. Tungsten (W) and Copper-alloy (CuCrZr) have been considered as the potential candidates for armor materials and heat sinking materials, respectively, due to their attractive nuclear and physical properties. However, due to the incompatibility of the coefficient of thermal expansion and the elastic properties between the W and the Cu-alloy as well as the non-homogeneous temperature distribution in PFCs, one of the crucial issues is the generation of thermally-induced residual stresses in W/CuCrZr PFC on cooling either during fabrication or during operation of fusion reactor. Therefore, the thermo-mechanical response of PFCs under high heat flux from the fusion reactor is a critical issue for the development of fusion technology. In the present work, in order to optimize the thermal and mechanical integrity of PFCs, thermally-induced residual stresses in W/CuCrZr PFCs with a compliant interlayer (OFHC-Cu: Oxygen Free High Conductivity Copper) are analyzed numerically by means of finite element method. Result indicated that the use of interlayer in PFCs could significantly reduce the magnitude and the concentration of thermally-induced stresses in comparison to the PFCs without interlayer. And also the optimum thickness for interlayer was suggested based on the current analysis conditions.
The Thermal-Mechanical Coupled FEM Analysis on 3-Roll Continual Tube Rolling PQF Deformation Process
Authors: Wang Fei Xue , Du Feng Shan , Yu Hui
Published: February 2011

Based on the characteristics of PQF deformation process, a thermal-mechanical coupled model of this process is established by the three-dimensional elasto-plastic finite element method. The simulation according to practical rolling process of a certain factory is completed. Some important parameters such as the finished size of the rolled product, the temperature variation curves of the key nodes on the tube, the rolling force and torque of each roller are predicted during this simulation. Comparison between simulation solutions and experiment results shows a good agreement, which means this model is capable of simulating PQF deformation process as well as forecasting product quality.
Influence of Process Parameters on Plastic Injection Molding of Automobile Interior Trim
Authors: Liu Qing Qing , Hua Lin , Guo Wei
Published: February 2011

The influence of process conditions on the formability of injection-molded PX0034 (9% talc-filled PP) automobile B column mounting trim applied as a model has been studied in current work. This study has been focused on the interactive influence of melt temperature and mold temperature, the interactive influences of injection time and packing time and the influences of packing pressure. Weighting the effect of optimization is by formability including the values of pressure at V/P switchover, volumetric shrinkage differential at ejection, and maximum warpage. Aforementioned values were obtained by numerical simulation of the whole molding process using commercial dedicated code Moldflow. Results indicate that the combination of mold temperature at 25 °C, melt temperature at 220 °C, injection time at 2.2 s, packing time at 16 s and packing pressure at 90% of the filling pressure is the optimal setting for formability of this trim. The simulation results obtained under the optimized parameters are that the pressure at V/P switchover is 27.29 Mpa, the shrinkage differential at ejection is 6.55 %, and maximum warpage is 3.072 mm. Good correlation is highlighted between the experiments and the simulations by comparing effects of the global optimization in formability, which verifies the validity of the optimal combination.
An Image-Based Microscale Simulation of Thermal Residual Stresses in DSE Oxide Ceramic Composite
Authors: Sha Jian Jun , Ochiai S. , Okuda H. , Iwamoto S. , Morishita K. , Waku Y. , Nakagawa Narihito , Mitani A. , Ishikawa T. , Sato M.
Published: February 2011

An image-based microscale analysis was conducted by using finite element method (FEM) to simulate the thermal residual stresses in directionally solidified eutectic (DSE) oxide ceramic composites from the thermal expansion and elastic properties and the microstructure features of the constituent phases. This microscale analysis allows a real simulation of morphologies of constituent phases such as size, array and shape. Meanwhile, this model can be applied not only for the calculation of thermal residual stresses, but also for the calculation of mechanical properties. In this work, simulations focus on the distribution of thermal residual stresses in the directionally solidified eutectic (DSE) Al2O3/ Y3Al5O12 (YAG) ceramic composite. A good agreement between simulated and measured thermal residual stresses was observed.
Research on the New Compound Technology of Integral Seamless Housing of Rear Axle
Authors: Ma Jun , Han Ying Chun
Published: February 2011

In order to save energy and material, and reduce productive costs, in accordance with the geometrical characteristics of rear axle housing of trucks, the redesign of integral product with new technology was completed, and then, two kinds of forming technology were developed. Afterwards, rear axle housing of light trucks was formed by adopting hydraulic bulging and neck-spinning, and the housing of heavy trucks by adopting hot mechanical expanding and hot neck-spinning with the tube. The research of this paper has practical value and results in great economic returns.
Simulating Design of Magnetic Fluids Lubricating Unit Structure with Porous Material
Authors: Hu Rui , Liu Zuo Min , Xu Chun Xia
Published: February 2011

In order to enhance the lubricating capacity of the magnetic lubrication on the surface of the porous material, a new magnetic lubricating field has been designed by simulating method based on the coupling relationship between the pores and micro-magnets structure. The results show that the output characteristics of magnetic fluids in the pores of the material play a significant role in the design, whereas the output characteristics depend on micro-magnets and the pores’ size such as length and diameter, for example, when the ratio of length/diameter of the pore is larger than 3.2 ,the output capacity of the magnetic fluids in the pores presents a stable value, but when the ratio is smaller than 3.2, the output capacity obviously decreases. It is also found when the distance among the pores changes from 5 mm to 8 mm, the output capacity also presents a stable value; however, the output capacity obviously decreases with the increased distance among the pores beyond 8 mm. Furthermore, the effect of the parameters of micro-magnets structure on the output capacity of magnetic fluids is also investigated in the paper. The research results are helpful to improve the lubricating properties of the magnetic fluids on the surface of the porous material.
Finite Element Analysis for the Wind Resistance of the Tower of Wind Turbine
Authors: Wei Hua , Cheng Yan Jun , Peng Zhi Yuan , Wang Hai Jun
Published: February 2011

1MW variable speed constant frequency wind turbine tower of steel structure is analyzed by using the software ANSYS, the coupling between the wind and the tower is realized through the order coupling method. The maximum Von Mises stress and the deformation of the tower in the case of limit loads are obtained, and then these results are compared with that without wind load. Comparison result shows that the effect of wind load on the tower’s displacement along the wind speed is great, and the maximum Von Mises stress of the tower becomes larger after considering the influence of wind load, the increase extent is determined by wind load case.
Study on Process Concentrating of a Certain Limonite Ore in Xinjiang
Authors: Zhang Jin Xia , Niu Fu Sheng , Liu Shu Xian , Nie Yi Miao
Published: February 2011

Based on the study on the characteristics of a limonite ore, research was made on single reverse flotation for Xinjiang limonite ore. The test results indicate that we can obtain an iron concentrate grading about 54.07％ at a recovery of 62.65％ from an iron ore assaying around 41.85％ iron，rather good metallurgical performances.
Friction and Wear Characteristics of Electrodeposited Ni-MoS2/Al2O3 Composite Coating
Authors: Huang Zhong Jia , Xiong Dang Sheng , Li Jian Liang , Liu Ming Lang
Published: February 2011

The MoS2 powders was coated with Al2O3 ratio varying 5wt.% to 50wt.% content. Ni–MoS2/Al2O3 composite coatings were prepared by means of pulse electrodeposition in a nickel-plating bath containing MoS2/Al2O3 powder to be co-deposited. The dependence of surface morphology, microhardness and tribological properties of the composite coatings was investigated in relation to the Al2O3 ratio in MoS2/Al2O3 powder. The results demonstrate that the coating co-deposited with MoS2/50wt.%Al2O3 showed a compact and fine granular surface morphology; the highest microhardness and wear resistance. The hardness of Al2O3 is responsible for this improvement.
On Resistance Calculation for Autonomous Underwater Vehicles
Authors: Song Fang Xi , Zhang Lian Hong , Wu Zhi Liang , Wang Le Ping
Published: February 2011

Investigation on the turbulence model for resistance calculation for autonomous underwater vehicles (AUV) with the typical Myring shape is presented in this paper using computational fluid dynamics (CFD) method. Resistance calculations of the 3D viscous flow over an AUV model are made by solving RANS equations with different viscous models. Comparison with experiments indicates that the SST k-ω two-equation viscous model is the most appropriate model for the resistance prediction.
Experiment and Numerical Study of Annular Flow Entrainment Mechanism in Oil-Air Lubrication Pipe
Authors: Cai Lin , Wang Jin Li , Zheng Hong Tao
Published: February 2011

Annular flow is a based flow pattern of two-phase in the pipe, and oil air flow in delivery pipe of Oil-Air lubrication (OAL) system is one of them. In order to learn the entrainment mechanism of annular flow in OAL pipe, both experiment adopted observational method and numerical simulation used Computational Fluid Dynamic (CFD) were carried out. The pipe diameter is 4mm and Volume of Fluid (VOF) model was used for two phase flow in simulation. The results shows that: it is a wave-annular flow in OAL pipe, and the oil wave in pipe is affected by air, when air velocity is low, the wave is clearly and regularly, but when air velocity increases, the wave become turbulent. When oil or air flow rate increases, the shear stress of pipe wall will be increased, the wave height will be increased as air velocity increases.
Modeling and Analysis of Soft Contact in Robotic Grasping Using Bond Graph Methods
Authors: Khurshid A. , Ghafoor A. , Malik M.A.
Published: February 2011

Soft fingers contribute to dexterous grasping on account of the area contact and high friction involved. This paper presents a novel approach in modeling of soft contacts between soft fingertip and object using viscoelastic material and analyses its characteristics employing BondGraph Methods (BGM). The fingers are made viscoelastic by using springs and dampers. Detailed bond graph modeling of the contact phenomenon with two soft-finger contacts considered to be placed against each other on the opposite sides of the grasped object as is generally the case in a manufacturing environment is presented. The stiffness of the springs is exploited in order to achieve the stability in the soft-grasping which includes friction between the soft finger contact surfaces and the object. It is shown in the paper that the system stability depends on the viscoelastic material properties of the soft interface. Method of root locus is used to analyze this phenomenon. The paper shows how the weight of the object moving downward is controlled by the friction between the fingers and the object during the application of contact forces by varying the damping and the stiffness in the soft finger.
Study on Controlled Release Properties of Slow-Release Pellets
Authors: Zhang Qiu Liang , Guo Lei , Xiong Shan Bai , Zhao Si Ming
Published: February 2011

The first-order kinetic models were used in the article to study the effect of the addition of gum acacia (A1), the ratio of core material and wall material, the ratio of maltodextrin and starch, and the gel types on the release properties of pellets in distilled water. The results showed that the sucrose release rate (K values) of slow-release pellets slowed down gradually with the increase of A1 amount, larger ratio of wall material resulted in smaller K values, the ratio of starch increased from 2:1 to 1:1, K values at different water temperatures increased significantly, additional starch might result in the blocking of elution tube by pellets and smaller K values of the pellets, K values of the pellets prepared with gum acacia (A2) was the maximum and that with A1 was the minimum, and the compound of A1 and A2 could control the release rate of the pellets. The release process of the pellets in the static distilled water system showed that the pellet diameter (D1) expanded rapidly in the early period, then the pellet wall surface eroded, pellet size expansion slowed down until insoluble starch circle was left. The pellet core diameter (D2) changed a little in the early period and decreased faster after a period of time until it was completely dissolved. The release process of pellets in the static distilled water supposed that there were two stages of sucrose release from the pellets, and the model fitting results showed: the K values in the first stage was significantly higher than those of the second stage.
Application of Support Vector Machine to Predicting Mechanical Properties of TC4
Authors: Hou Zhe Zhe , Du Yan Liang , Zhao Wei Gang , Zhao Meng , Peng Shuang Chao
Published: February 2011

On the basis of numerous experimental results the effect of heat treatment on mechanical properties of TC4 alloy is studied. A computer model expressing the relationships between heat treatment and mechanical properties has been established with supported vector machine method. The input parameters were determined by the heating temperature and heating time which are important factors of the mechanical performance, and the output parameters are tensile and yield strength and elongation. The model is established by libsvm with RBF kernel function, e-SVR and proper parameters. Experimental results show that prediction accuracy made by using support vector machine reached over 95%, and the model has good learning precision and generalization and it can be used for predicting the mechanical properties of TC4 alloy.
Numerical Simulation of Different Clamping Modes on Stretch Forming Parts
Authors: Chen Xue , Li Mine Zhe , Fu Wen Zhi , Cai Zhong Yi
Published: February 2011

Three clamping devices of stretch forming machine were introduced, and the corresponding finite element models of the spherical parts were built by finite element software, the strain and thickness distribution of the forming parts were comparatively analyzed. The simulation results show that strain and thickness distribution of the forming parts with the multiple discrete gripper clamping mode are well-proportioned, its forming quality gets better than that with the whole flat gripper and adjustable curved gripper clamping modes. The experiment was performed and a typical spherical parts was formed with the multiple discrete gripper clamping mode. The experimental results are in good agreement with simulation results, which proves feasibility and practicability of the multiple discrete gripper clamping device of stretch forming machine.
Study on Contractive Rate Inspecting Testing Mould of Thermoplastic
Authors: Liu Geng Wu
Published: February 2011

As we know , the materials will swell and contract when it is heated or cooled . A kind of method for mastery the real contractive rate of thermoplastic was bring forward through researching the contractive rate of thermoplastic . Using the method a inspecting testing mould of thermoplastic was designed , and the real contractive rate was masteried by the mould . And this provides the reliable contract date for the design of mould cavity dimension , and reduces the work of mould repair , and also save a lot of money and labor.
Study on Metal Flow in Continuous Extrusion Cladding of Cable Aluminum Sheath Using FEM Analysis
Authors: Zhao Ying , Song Bao Yun , Pei Jiu Yang , Yun Xin Bing
Published: February 2011

This paper analyzed continuous extrusion cladding process through 3D FE simulation in the non-steady state. The model is used to predict the metal flow characteristics during the entire process. According to the metal flow characteristic, continuous extrusion cladding process is classified into feeding, welding, filling and forming stages. The modeling results predict temperature, stress, strain rate and velocity fields. When the metal flows through the die bearing, the velocity distribution is non-uniformity, because of the non-symmetrical structure and the difference in temperature of the upper and bottom portion of the die cavity. And FEM results also show that the velocity distribution is sensitive to the change in mandrel radius. Increasing the mandrel radius can relatively improve the metal flow velocity in the upper cavity and decrease the velocity in the bottom cavity. There is an optimum mandrel radius value that makes metal flow most uniform. These also provide the theoretical basis for optimizing the technology and the die design.
Comparison of Different Content of Cd and Sb Element on the Microstructure, Mechanical Properties of As-Cast AZ31 Magnesium Alloy
Authors: Luo Xiao Ping , Xia Lan Ting , Zhang Ming Gang
Published: February 2011

The effect of Cd and Sb addition on the microstructural and mechanical properties of as-cast AZ31 alloys was investigated and compared. The results indicate that the difference of Sb and Cd in the microstructure and mechanical properties of as-cast AZ31 magnesium alloy is significant. Addition of 0.15%Sb (mass fraction) to AZ31 alloy can refine the matrix and β-Mg17Al12phase but not form a new phase Mg3Sb2. Oppositely, by addition of 0.3-0.7% Cd to AZ31 alloy, Cd was dissolved into the AZ31 alloy, the phase composition did not change but was refined also. Accordingly, the Cd-refined AZ31 alloy exhibits higher tensile and impact toughness and Brinell hardness properties than the Sb- refined one. The difference of Sb and Cd in the mechanical properties is possibly related to the solid solution of Cd into the matrix and formation of Mg3Sb2which has the same close-packed hexagonal structure as α-Mg.
Temperature Field Modeling and Thermal Deformation Analysis of Turning and Milling Machining Center
Authors: Liu De Ping , Li Jie , Su Yu Feng , Wang Yu Ping
Published: February 2011

Taking the high-speed CX series vertical milling compound machining center of CX8075 produced by Anyang Xinsheng Machine Tool Co., Ltd. as example, the machine three-dimensional simplified model is established, the source of the heat and the distribution of the important hot-points are analyzed, the machine temperature field distribution is derived which lays a foundation for the thermal error compensation. Taking into account the moving part-saddle of the machining center, its mathematic model is obtained, the important hot-points are studied, the thermodynamic parameters are determined. Based on ANSYS finite element method, the steady-state temperature field and the thermal deformation of saddle are presented, the optimal design of high-speed and high-accuracy machine tool is doned and its thermal deformation analysis is realized.
Numerical Simulation of Flow Field in Cavitations-Impinging Stream Reactor
Authors: Li Qin , Wang Hui Lin
Published: February 2011

Based on standard k-ε model of Fluent, the 3-D numerical simulation of cavitations-impinging stream reactor was studied. The main flow law in the reactor was obtained, and its velocity and pressure fields were analyzed. The results showed that the parameters of the flow field were completely symmetrical by the impinging surface; isobar concentrate in the impinging area which indicated that pressure fluctuations in this region is stronger, it plays an active role on the promotion of flow group micro-mixing. The laws of parameters influence on impinging phenomenon were revealed by analysis the results with different parameters. The basic data and theoretical bases are provided for the optimized and improved design of impinging streams reactor.
A Numerical Study on the Uplift Behavior of Under-Reamed Anchors in Silty Sand
Authors: Hsu Shih Tsung
Published: February 2011

Ground anchors are common to be employed in geotechnical engineering. Under a limited space of an urban district or a restricted thick of an anchored stratum, an under-reamed anchor could meet both the requirements of a short length and a high anchorage capacity. To investigate the anchorage mechanism of the anchor, a series of triaxial tests was performed to obtain the parameters demanded for a constitutive model, SHASOVOD (A continuous strain hardening/ softening and volume dilatancy model for cohesionless soil during stressing). A numerical program was then developed to study the uplift behavior of the under-reamed anchor in silty sand. Analyzing results show that, for two under-reamed anchors located in different test sites, the complete load-displacement curves estimated numerically were consisted with those measured from the field test. The total load, friction load and end bearing do not reach their peaks simultaneously. According to the behavior of the end bearing, a critical overburden depth H of 6D was found to classify an under-reamed anchor as a shallow anchor or a deep anchor.
Modeling and Simulation of Gear Transmission System of Drive Axle with Romax
Authors: Ye Zhen Nan , Zhang Wen Ming , Jiang Yong , Jiang Zhi
Published: February 2011

Drive axle is a key part of transmission system on the articulated vehicle. Its stability has a great influence on the performance of the truck. The gear transmission system of 45t articulated vehicle drive axle is taken as an example while the virtual prototype models of drive axle gear transmission system are established with Romax. The comparative simulation analysis of fatigue life of drive axle supporting bearing is performed through two means, the ISO281 and Romax Adjusted, which are methods for predicting bearing fatigue life. The results of simulation show that each supporting bearing has long life, low wear rate and long working time; the prediction of bearing fatigue life with Romax Adjusted agree with the actual work condition of bearing.
The Simulation of Polycrystalline Silicon Thin Film Deposition in PECVD System
Authors: Wang Zhi Jian , Shang Xiao Feng
Published: February 2011

Taking Silicon tetrachloride (SiCl4) and hydrogen (H2) as the reaction gas, by the method of plasma-enhanced chemical vapor deposition (PECVD), this paper simulates the deposition process of polycrystalline silicon thin film on the glass substrates in the software FLUENT. Three dimensional physical model and mathematics model of the simulated area are established. The reaction mechanism including main reaction equation and several side equations is given during the simulation process. The simulation results predict the velocity field, temperature distribution, and concentration profiles in the PECVD reactor. The simulation results show that the deposition rate of silicon distribution is even along the circumference direction, and gradually reduced along the radius direction. The deposition rate is about 0.005kg/(m2•s) at the center. The simulated result is basically consistent with the practical one. It means that numerical simulation method to predict deposition process is feasible and the results are reliable in PECVD system.
Minimizing the Warpage and Sink Mark Depth in Injection-Molded Thermoplastics
Authors: Guo Wei , Hua Lin , Mao Hua Jie
Published: February 2011

This paper deals with minimizing warpage and sink mark depth in injection-molded thermoplastics components. Automobile glove box housing trim assembled on the instrument panel was chosen as an experimental model. In these experiments, the Taguchi method and FE analysis were used to research minimizing the warpage and sink mark depth. The most influential factor was found out by using Taguchi method. Through interaction parameters experiments put into practice through Moldflow software, the interaction between each factors has been researched. The optimization packing condition for minimization of the warpage and sink mark depth was designed.
Axial Spread Evolution during Hot Rolling of Large Rings with Different Sizes
Authors: Wang Min
Published: February 2011

For ring rolling without axial rolls, how to effectively suppress axial spread has become an important subject. In the paper, a reliable coupled thermo-mechanical three-dimensional (3D) finite element (FE) model for hot rolling of large rings is developed. Spread evolution of titanium alloy large rings with different sizes are explored and compared based the developed model. The main results show that (1) the spread in a ring takes on an axisymmetric distribution after the first revolution of the ring. (2) with the equivalent ratio of feed amount per revolution decreasing, the peak spread transfers from the outer layer to the inner layer for rings with different sizes.
The Numerical Simulation about Second Dendrite Spacing of Low Pressure Casting Automobile Aluminum Magnesium Alloy Wheel
Authors: Zhao Xin , Sui Yan Wei , Liu Ai Hui , Wang Fei Fei , Sun Zhi , Hao Zhi Jiang
Published: February 2011

Using the method of numerical simulation and the AnyCasting software, the simulation for SDAS of Al-Mg alloy wheels for low pressure casting is studied. The simulation model is established and the effects of preheating temperature, melt pouring temperature and cooling water pipes on SDAS in the low pressure casting process was founded. The results show that, SDAS presents linear variation with the increase of preheating temperature and pouring temperature; opened cooling pipes make SDAS smaller. The practice of simulating casting is verified by experiments, and test results and simulation results were consistent.
Study on Ultrasonic Surface Rolling Process Using FEM Analysis
Authors: Liu Yu , Wang Li Jun , Wang Dong Po
Published: February 2011

Ultrasonic surface rolling processing (USRP) is a surface nanocrystallization method developed recently, which can bring metal surface with superior properties. In order to obtain the material response during USRP, a 3D dynamic finite element model was adopted to study the effects of parameters. This model was validated by experimental results of residual stress. Simulated results indicate that large ultrasonic vibration parameters generate high stress and strain, where static pressure plays a more important role than vibration amplitude. Yet high spindle speed leads to small stress and strain.
Solder Joints Reliability Assessment for Stacked CSP Module Based on Flexible Circuit Printed Board
Authors: Yan Hai Dong , Zhou De Jian , Zhao Qiang
Published: February 2011

Solder reliability assessments for stacked CSP module based on flexible printed circuit board (FPC) are performed in this research using a 3D global model with constraint equation and two levels submodeling technique. 3D global model with constraint equation(CE) was used to provide real boundary contiditons for 1st level submodeling,and quarter local model used as 2ndlevel submodeling was used to address cirtical solder joint failure locations ,to estimate solder reliability for the module and to provide reasonable boundary contiditons for 2ndlevel submodeling.slice model used as 2ndlevel submodeling was used to study that the effect on the cirtical solder damage parameter under various basefilm material of FPC and geometrical parameters. It is found that thinner CSP die thickness and thinner PCB ,thicker FPC basefilm and FPC adhesive thickness and CSP thickness,and higher solder standoff height, lead to smaller averaged accumulated viscoplastic strain energy density(ΔWavg) and higher fatigue life; It is also figures out,PI and PEN basefilm material lead to smaller ΔWavg and higher fatigue life for the most critical solder than LCP material.Weibull distributions and weibull probaility density function for the module under various FPC baseflim material were obtained,and 63.2% solder joints failure life was used as solder joints reliability assessment for stacked CSP module.
Mechanism Analysis of Magnetostrictive Turning for Piston Skirt Processing
Authors: Li Cheng Ying , Zhang Jin , Wei Wei
Published: February 2011

The paper presents a turning method by using the magnetostrictive transducer as drive source, this method set up a self-made magnetostrictive tool-post on the CNC lathe. Theoretically, based on the theory analysis of piston skirt varying to oval cross section and middle-convex mold line, this paper expounds the reality of the magnetostrictive turning machining mechanism of middle-convex and varying surface. Experimental results show that this method can not only satisfy the requirements of design, but also simplify workpiece process, establishing theoretical and experimental basis for magnetostrictive material applied to the piston skirt middle-convex and varying surface truning machining.
Research on Rapid Prototyping Machine of Ceramic Parts and the Machine Control System
Authors: Gao Dong Qiang , Zhang Fei , Guo Zhi Gang
Published: February 2011

The topic is according to the laminated-speed Gel-type technology to design all the parts of the RP machine, establish the 3D model，assemble the parts together by Pro/E，set the parameters, such as motor parameters and so on, and finally achieve the 3D simulation of the device. The real movement process can be seen by the simulation. It is also available to analyze the rationality of the design according to the simulation. Besides, ANSYS is used to analyze the distortion of the workbench, and a certain degree of distortion is found to have affected the precision of the ceramic parts process at some extent. Based on this, the structure is changed and analyzed again, and then all the requirements have been met. At last, a control system is designed in accordance with requirements of the rapid prototyping machine. Thus the whole design of the machine is completed.
3D Finite Element Modeling for Particle-Reinforced Polymer Composites for Wind Energy Application
Authors: Wang Huai Wen , Ji Hong Wei , Shao Wen Quan , Miao Hui
Published: February 2011

A series of numerical meso-mechanical models for different kinds of particle (include spherical, cylindrical and discal) reinforced composites are developed to investigate the effect of microstructural parameters on the elastic properties of composites. In these models, an effective interface concept is adopted. Finite element models with prescribed and random parameters are automatically generated in ABAQUS PDE (Python Development Environment). In the simulative investigations, it is observed that the degree of particle clustering and particle’s shape have strong effects on the elastic mechanical properties of composites.
Expansion Order Effect on Residual Contact Pressure of Tube to Tubesheet Joint by Hydraulic Expansion
Authors: Huang Xiao Ping , Zhang Ding
Published: February 2011

For better understanding the expansion order effect on the residual contact pressure between tube and tubesheet, numerical simulations of multi-tubes expansion were performed by using ANSYS software. Two sets of different materials of tubes and tubesheets under different expansion orders have being analyzed in the present paper. The simulation results show that the residual contact pressure between one tube and the tubesheet decreases with the increasing number of expanded tubes around it, and reaches a certain value gradually. The expansion order of “top to bottom, left to right” which is used in the actual production process can provide a higher residual contact pressure than other expansion order by comparing the results of two different expansion orders. The material properties of tube and tubesheet have significant influence on the residual contact pressure when the expansion pressure is the same.
Analysis on Internal Gear Stress for Design Parameters
Authors: Han Gang , Wang Song Lei
Published: February 2011

In the paper, it analyzed the influence of gear stress for different design parameters of modified internal gear with ANSYS software. Though specific examples, the diagram of the relation between design parameters and stress was obtained, and some useful conclusions were provided for internal meshing gears transmission reference in design.
Numerical Simulation of Plate Bender Bending Process
Authors: Liu Xue Jiang , Liu Hai Sheng , Liu Jing , Wang Hui Gang
Published: February 2011

The plate’s mechanical behavior of three-roller plate bending machine had been analyzed in case of upper roller feeding based on ANSYS. Strain and stress distribution of the plate and its changes are gained. The influence of upper roller’s feeding location and bending velocity to bending process are researched. The results are valuable to bending process optimization and practical technique of plate bending.
Flow of Finite Element Analysis of Metal Powder in Medal Injection Mold Runner
Authors: Jin Jie , Bai Xin , Ning Fang Yin
Published: February 2011

Based on the continuum theory, combined with the characteristics of metal injection molding, constructs assumptions and control equation in the die filling process of MIM.With the FLOTRAN hydro-analysis module of ANSYS software, the melt’s velocity ,temperature and pressure fields during injection molding were simulated and compared for different sizes of circular section runners,and discussed the influences between different diameter runners and injection pressure on the flow behavior of melt. The simulation provided theoretical guidance for the design and selection of mold runner in the production.