bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Heating Vents in a Tunnel-Type Dryer
Authors: Tsai Chien Hsiung , Wang Yao Nan , Tai Chang Hsien , Miao Jr Ming , Leong Jik Chang
Published: February 2011

This work employs FDS to simulate the heating process of a tunnel-type dryer and visualizes the computational results using Smokeview. The inappropriate design of a tunnel-type dryer in a factory has motivated this work. This poorly designed dryer not only has caused terrible fuel consumption but also produced parts some of which are under- or over-cooked. These are caused by the terribly uneven temperature distribution within the dryer. In order to improve the evenness of temperature distribution, this work simulates and investigates the effects of various ventilation schemes. Based on the results, it is found that the hot air intake vent should be placed at the bottom whereas the cold air outtake vent at the top. The flow rate through the intake vents does not have a very significant effect on the temperature distribution after 40 s.
The Effects of ZigBee Position with Different Hidden Layers in Back-Propagation Neural Network
Authors: Liu Fang Tsung , Weng Ceweng Erh , Huang Chien Ming , Yang Chang Yan , Huang Huang Chu
Published: February 2011

In this paper, the research topic is that the expert experience is established by the size of the measured signal strength of wireless sensor networks and put the strength of the actual collection of historical data into the neural network model. In order to get the minimize error we use the errors to modify the weights and threshold of the neural network links. We compare the differences of hidden layer neural network and the experimental results. We set up a wireless sensor networks environment to collect the measurement values of signal strength (RSSI) and develop an indoor positioning system.
Influence of Liquid Phase Migration on Intermittent Extrusion of Aqueous Al2O3 Paste
Authors: Liu Hong Jun
Published: February 2011

Extrusion Freeform Fabrication Process (EFF) is an environmentally friendly solid freeform fabrication method that uses aqueous pastes to fabricate ceramic-based components. The Liquid Phase Migration (LPM) causes variation in liquid content and consequently problems in the paste extrusion. To get uniform ceramics parts with desired composition, the LPM should be avoided in extrusion process. This paper investigated the influence of LPM on extrusion process for aqueous alumina paste in EFF process. It shows that the liquid phase migration occurs in Freeform Extrusion Fabrication process and has a strong impact on extrusion pressure. The LPM can be characterized by the extrusion pressure-ram displacement profiles. The liquid phase migration becomes more serious in intermittent extrusion at low ram velocity.
Influence of Heating Models on Necking Deformation during Tube Extrusion Process
Authors: Liu Gui Hua , Guo Yong Qiang , Jiang Zhi
Published: February 2011

By using Deform-3D software, the necking extrusion forming processes of integer trailer axle with two different heating means which are Uniform Heating (UH) method and Partly Heating (PH) method with temperature gradient are simulated. The influence of deformation parameters such as friction factor, necking coefficient, different temperature distribution of work-piece on the material flow features, stress and strain field, loading force and deformation process are analyzed in detail. According to the numerical simulation results, using PH method with temperature gradient can improve necking deformation during tube extrusion process.
On the Dispersants of Diamond-Ni-P Composite Electroless Plating and Properties of the Coating
Authors: Feng Li Ming , Wei Xue
Published: February 2011

In order to obtain stable and homogeneous diamond-Ni-P composite electroless plating, dispersants were selected by determining the height of emulsion in the colorimetric cylinder after standing different time.The structure,elemental contents and properties of the diamond-Ni-P composite electroless plating coating were investigated by SEM and EDS. Experimental results show that OP-10 of 50mL•L-1 and softex kw of 1g•L-1 have better dispersing effect to diamond powder of 1g•L-1 in water. This composite electroless plating solution can keep stable for more than twelve or eight hours respectively at 85°C. While in the electroless plating solution, Softex kw of 1g•L-1 has better dispersing effect and can be stable for more than two hours at 85°C. The diamond powder grains in the composite coating are homogeneous and the content of carbon is 2.261 wt% under the certain amount of the selected dispersant. When the content of diamond was 5g•L-1 in the solution, the diamond powders were dispersed non-homogeneously in plating and cluster phenomena were appeared. The composite electroless plating coating consists of amorphous Ni-P and diamond powder. Its hardness and porosity are similar to those of the electroless plating Ni-P coating. The wear-resisting is improved greatly,which is 2.6 times of electroless plating Ni-P or 2 times of that after heat treatment at 400°C for one hour.
Study on Angular Stiffness of Monolithic Flexible Joint
Authors: Liu Chun Jie , Wang Xi , Wan De’an
Published: February 2011

The monolithic flexible joint is introduced as a novel component of inertial guidance instrument. The angular stiffness of the joint is investigated by employing theory of flexure hinges considering the key part of the joint is a variation of the common circular flexure hinge. Closed-form equation is formulated to unify the typical angular stiffness equations developed by other authors in terms of the circular hinge, and the main variables of the formulation are also discussed. Finite element models of the monolithic joint are built to confirm the analytical model predictions. A measuring system controlled by computer is also developed to evaluate the angular stiffness of the monolithic flexible joint. Checked against finite element analysis and experimental measurement data, the analytical model predictions are within 7% error margins. The study results indicate that the angular stiffness is more sensitive to the minimal thickness of hinge and less sensitive to the notch angle and the oblique angle of hinge.
Analysis of Mechanical Properties of Pipes with Helical Reinforcement under Axial Tension
Authors: Huang Wei , You Zhong
Published: February 2011

Flexible pipes with helical reinforcement are widely used in the marine engineering and tissue engineering because of their low bending stiffness. Through appropriate design, they could also meet the strength requirement. All studies on this kind of structures regard the pitch angle of helical wires, strips or fibers as a vital parameter influencing the mechanical properties. In this study, we compare the tensile property of pipes with helical reinforcements braided in different initial pitch angles. Contact pressure is taken into consideration and eliminated by using deformation compatibility equation. The pitch angle changes under axial tension which induces the geometric nonlinearity. It is noted that when the pitch angle is larger than a critical value, even if there is no internal or external pressure, helixes will contact with the core under axial tension. But the initial pitch angle can not be too large since the contact pressure will induce partial buckling of the flexible pipe.
Study on the Distribution Law of the Crashed Coal Fragmentation
Authors: Zhang Jia Jia , Du Chang Long , Liu Song Yong , Jiang Hao
Published: February 2011

In order to find the distribution law of coal fragmentation, mathematic model of size distribution was built according to fractal theory. Based on this, the experiments of impactive crash were carried out under different impact rate and different Protodikonov's hardness. The comparison between Weibull distribution and fractal distribution was done so as to find the relationship between the influence parameters and the coal fragmentation characteristic index, the coal fragmentation degree coefficient and the fractal dimension. The results indicate that both two types of distribution functions are suitable for the distribution discipline of coal fragmentation, but the relationship of the coal fragmentation degree and impact parameter is not reacted correctly by the coal fragmentation characteristic index and coal fragmentation degree coefficient in the Weibull distribution while the coal fragmentation degree could be expressed by the fractal dimension in fractal distribution. The relationships between the fractal dimension and the rate, the Protodikonov's hardness of coal are linear.
Numerical Analysis on Impact Load of Elasto-Plastic Spherical Impact
Authors: Du Chang Long , Liu Yu , Li Jian Ping
Published: February 2011

The spherical impact is a common phenomenon in mechanical engineering. The elasto-plastic impact is more complicate than the elastic impact. The elasto-plastic impact loads are investigated for the different contact stiffness and the different impact velocity by the nonlinear finite element method. The accuracy and reliability of the finite elements model are verified by comparing the numerical results of the elastic impact with the Hertz results. The elasto-plastic impact simulation shows that the impact loads have a negative exponential relation with the contact stiffness as well as a linear relation with the impact velocity. The contact time decrease with the increase of the contact stiffness and the impact velocity. The comparison between the influence of the contact stiffness and the impact velocity indicates that the impact velocity has a significant influence on the impact load and the contact stiffness has a big influence on the contact time.
Laser Anneal-Induced Effects on the NBTI Degradation of Advanced-Process 45nm High-K PMOS
Authors: Wan Muhamad Hatta Sharifah Fatmadiana , Abdul Hadi Dayanasari , Soin Norhayati
Published: February 2011

This paper presents the effects imposed on the reliability of advanced-process CMOS devices, specifically the NBTI degradation, subsequent to the integration of laser annealing (LA) in the process flow of a 45nm HfO2/TiN gate stack PMOS device. The laser annealing temperatures were varied from 900°C to 1350°C. The effects imposed on the NBTI degradation of the device were comprehensively analyzed in which the shifts of the threshold voltage and drain current degradation were observed. The analysis was extended to the effects of the conventional RTA as opposed to the advanced laser annealing process. It was observed that the incorporation of laser annealing in the process flow of the device enhances the NBTI degradation rate of the device, in contrast to the integration of the conventional RTA. Laser annealing subsequent to spike-anneal is observed to improve the reliability performance of the transistor at high negative biases.
Optimization Technique for Neural Network-Based Error Compensation in CNC Machining
Authors: Fan Kai Guo , Yang Jian Guo
Published: February 2011

The neural network (NN) is extensively used for error predication and compensation in CNC machining. However, the training samples are finite and have some noises which limit the training accuracy of the neural network. Furthermore, the weight matrixes and the valve values of the NN are fixed which limit the generalization performance of the trained NN. To solve the problems, some optimization techniques are proposed in this paper. A standardized formula is proposed to standardize the training samples. The data filter is designed to eliminate the noise. A correction strategy is proposed to realize the generalization performance of the trained NN.
The Thermal Response Investigation of Functionally Graded Material Plates
Authors: Tian Jian Hui , Cao Yan , Wang Jian Hua , Xu Wei , Xu Xian Long
Published: February 2011

The displacement response of functionally graded material (FGM) plates has been investigated based on the strip element method (SEM) for temperature change. The material properties of the FGM plates vary continuously through the thickness. The temperature is assumed to vary continuously through the thickness. The displacement response is obtained for the FGM plates in the condition of temperature change action and both temperature and external force action. This study extends SEM to the heat response of the FGM plates considering heat effect. It is not only extension and development for the applicability of this method in thermal field but also provides a good theory reference for more applying SEM to the thermal field.
Influence of Guide Disc Postposition on Rolling Process of Accu-Roll Mill
Authors: Li Sheng Zhi , Ding Bo , Yin Yuan De , Hu Lan Wei , Meng Wen Hua
Published: February 2011

With the aid of commercial FE code MSC.SuperForm, the rolling process of Accu-Roll mill is simulated and the influence of guide disc postposition on the value of outside diameter expansion of elongated shell, force parameters and twist deformation of the workpiece are analyzed in detail. Analysis results indicate that the value of outside diameter expansion of elongated shell, guide disc force and the axial force of mandrel decrease when the value of guide disc postposition increases, but separating force and twist deformation of the workpiece increase, which provides scientific guidance for designing Accu-Roll mill and setting adjustment parameters.
Numerical Simulation of Polymer Flows in Coat-Hanger Die Using Wagner Constitutive Model
Authors: Li Yong , Zheng Jian Rong
Published: February 2011

An understanding of flow behavior of polymer melts through a slit die is extremely important for optimizing die design. In this paper numerical simulations have been undertaken for the flow of linear low-density polyethylene through Coat-hanger sheet dies. A new finite element method is proposed to simulate the flow in slit channel using Wagner constitutive model. This is one kind of finite element semi-analytical method by which the velocity distributions in thickness direction is approach by Fourier series. Numerical results of volumetric flow and pressure in coat-hanger dies are given to compare to the three-dimensional simulation using the finite element method. It appears that numerical solutions are as accurate as the complete 3D calculations and the computing time can be saved.
Mathematical Modeling and Modifying of Turntable’s Angle for 5/12 Automatic Numerical Controlling Bending Hoop Machine
Authors: Zhang Xiao Hong , Yin Guo Fu
Published: February 2011

Aiming at 5/12 full-automatic numerical control (NC) bending hoop machine, the paper analyzed the elastic-plastic bending deformation with the knowledge of elastic-plastic bending principle, theoretically mechanics and spring-back, and deduced the relationship of bending moment and curvature ratio, and built the mathematical model between bending hoop turntable’s rotation angle and stirrups angle considering the spring-back deformation. Then the different spring-back angles under two types of stirrups diameter, Φ=8 mm and Φ=10 mm, are measured. The mathematical model of turntable’s rotation angle and stirrup’s angle for 5/12 automatic NC bending hoop machine is modified according to the analysis of bending test data.
Contact Deformation and Abrasion Analysis of the Contact Region for Roller Linear Guide
Authors: Ma Jian Wei , Wang Fu Ji , Zhang Xue , Song Di , Zhao Xian Song
Published: February 2011

Directing an important kind of joints of the machine tool—roller linear guide, the force analysis of the contact deformation zone of it was presented. In this study, a new structure calculation model was applied to calculate the deformation of the contact area of the roller linear guide, and the contact zone deformation model was built. The abrasion for roller diameter at the middle and both ends was obtained by running test at last. The research results can provide reference to corresponding roller design and service life evaluation.
Optimum Design Study of a Hydraulic Pressure Derrick Based on Stability
Authors: Zhang Yu Lian , Zhang Hai
Published: February 2011

The bearing load is very large when the hydraulic pressure derrick suspends cargo. The hydraulic pressure derrick is a very important component which transfers cargo load to hull. The method of optimization theory based on dual method was transplanted to optimize the hydraulic pressure derrick structure and the optimizing model of the hydraulic pressure derrick was established. The hydraulic pressure derrick structure was optimized under four load cases. The numerical results show that the structure strength and stability of hydraulic pressure derrick are fit.
Evaluation Equation of the Flat Compression Properties of Corrugated Sandwich Structure
Authors: Wang Dong Mei
Published: February 2011

The flat compression properties of corrugated sandwich structure are an important factor to evaluate their cushioning properties. At present, more research has been made on the mechanical properties in the cross direction (CD) and machine direction (MD), but less has been made in the flat compression direction. Selecting corrugated paperboards as samples, we analyzed the flat compression properties of the corrugated sandwich structure and explored the critical stress which is a key element for evaluating the cushioning properties based on theory and experiment. It is convenient to evaluate the cushioning properties and optimize the corrugated sandwich structure. Simplifying the corrugated structure into the struts, and referring to the bending theory of the standard beam theory, we explored the evaluating equation of the critical stress for corrugated sandwich structure by the bending moment and Euler formulas. The critical stress is in direct proportion to the elastic modulus and the thickness of the basis material. It is also closely related to the length of the corrugated cell-wall and the pasted width between the corrugated cell-wall and the linerboard. Changing the above parameters, we can change the compression resistance of the corrugated sandwich structure. The theoretical value of the critical stress of the corrugated sandwich structure is higher than the experimental value, since the mechanical properties are lost when the basis material is manufactured into corrugated sandwiches and corrugated boards. Therefore, the lost coefficient is introduced into the theoretic equation which can not only help optimize and design the corrugated sandwich structure, but also find application in optimized design of cushioning pads of corrugated sandwich structure.
New Geometry of Face-Gear with Curvilinear Shaped Teeth and Non-Zero Spiral Angle: Machining Mathematical Model Analysis and Simulation
Authors: Wang Wen Jin , Zhang Zhi Qiang , Zhang Jing , Jian Zhao , Wang Tai Yong
Published: February 2011

New geometry of face-gear with curvilinear shaped teeth is proposed in this paper. The generation of the face-gear is based on application of a tilted head-cutter instead of application of a hob applied at present. The machining method for the gear is studied based on the differential geometry and meshing theory. The cutting simulation of the curvilinear-tooth gear is presented based on the developed gear’s machining mathematical model.
The Overview of Modeling the Thermo-Mechanical Three Dimensional Friction Stir Welding Process
Authors: Jiang Mei Ling , Wang Min , Chen Dong
Published: February 2011

A three dimensional thermo-mechanical model for FSW is presented. It's based on the model proposed by Alma H. Oliphant et al.[1] and Jacquin, D.et al.[2]. Velocity fields and initial plunge temperature profile are introduced in the steady state calculation of the temperature field during welding. And the non-adiabatic heat transfer conditions between the tool, the work piece, and the backing plate are also applied to the model. So a more accurate temperature will be got. It is anticipated that the model can be extended to optimize the FSW process parameters.
Modeling of Pillowing Stress in Corroded Lap Joints
Authors: Yu Da Zhao , Chen Yue Liang , Gao Yong , Liu Wen Lin , Zhang Yong
Published: February 2011

Based on chemical composition of the corrosion product, a mathematical model was developed to predict the extent of the pillowing deformation of lap joints of LY12CZ in term of thickness inside the joint. The model can offer the capability for predicting the extent of corrosion within the joint in terms of thickness loss at the internal surfaces of the skins from the amplitude of the pillowing of the outer skin. Three-dimensional finite element model of a bolted joint have been developed in the non-linear finite element code MSC.Marc and attempts were made to validate it by comparing results with the mathematical model. The results show that corrosion pillowing can significantly increase the stress in a lap joint for material loss below the detection limit of current nondestructive inspection techniques, thus increasing the risk of premature cracking. In addition, the analyses show that the locations of maximum stress of lap joint will change with the material loss increases. Simulating the effect of corrosion on lap joint only by reducing the panel thickness will result in neoconservative life estimates if corrosion pillowing is ignored.
Advanced Interactive Device in Virtual Knee Arthroscopic Surgery
Authors: He Yu Lei , Li Jin Fang , He Han Wu
Published: February 2011

Regarding the lack of interactivity for Virtual Knee Arthroscopic Surgery, which leads less immersion in simulated surgery, a new advanced interactive device in Virtual Knee Arthroscopic Surgery based on displacement sensor and Data acquisition card was developed. Based on study of degree of freedom on Knee Arthroscopic Surgery, a new interactive device on simulating real surgery was proposed. This device simplifies true operation for four degrees of freedom. Each displacement sensor captures information from one degree of freedom, then sends the information to the data acquisition card to carry out analysis and treatment for the purpose of synchronization on the computer, then realize realistic simulation of surgical procedures. The creative design of the interactive device makes it possible to flexibly adjust the location and angle of simulated scalpel and endoscope according to different operator and reach the requirement of immersion of virtual reality.
Optimization Research on Workpiece Clamping Deformation Using Genetic Algorithm and Finite Element Method
Authors: Sun Yu Wen , Zhang Chuan Tai , Guo Qiang
Published: February 2011

Optimal fixture involves fixture layout and clamping force determination. It is critical to ensure the machining accuracy of workpiece. In this paper, the clamping process is analyzed with the consideration of cutting forces and frictions using the finite element method. Then the fixture layout and clamping force are optimized by minimizing the workpiece deformation via a Genetic Algorithm (GA). Subsequently, linear programming method is used to estimate the stability of workpiece. It is shown through an example that the proposed method is proved to be efficient. The optimization result is not only far superior to the experiential one, but also the total optimization time can be reduced significantly.
Study on Electrical Resistance Tomography Simulation of Carbon Fiber Smart Layers on Two-Dimensional Curved Surface
Authors: He Chang Lin , Zhu Si Rong , Zhang Xiao Yu
Published: February 2011

Based on the piezoresistive function character and the conductivity of carbon fiber smart layer (CFSL), a novel electrical resistance tomography (ERT) system of spherical and cylindrical CFSL has been developed for global health monitoring. Based on the background of the third generation nuclear containment vessel, CFSL is stuck on the surface of the structure, and the effectiveness of the ERT system is verified by virtual experiment. The image reconstruction results show that CFSL on two-dimensional curved surface has good sensing characteristics in the complex strain state. Compared with structural volumetric strain in the monitoring area, it indicates that the high electrical resistance of CFSL is distributed in the high strain area of structures, and the low electrical resistance of CFSL is just distributed in the low strain area of structures. Therefore the resistivity’s distribution of CFSL can reflect qualitatively the structural volumetric strain field.
Numerical Simulation Analysis of Deformation in TIG Welding of I-Steel
Authors: Meng Ling Li , Huang Yan Qun , Liu Ming
Published: February 2011

Since it is inconsistent and uncontrollable in the experiment, any variance in specimen dimensions, welding parameters and testing conditions will influence the consistency of testing results to some extent. In this paper, the Finite Element Method(FEM) is employed to solve this problem. A three-dimensional finite element model is established to simulate the deformation of I-steel during gas tungsten arc welding (TIG) with FEM software, which is set up to analysis the deformation of I-steel with different welding sequences.
Virtual Simulation of Embedded-Vane Rotary Compressor
Authors: Geng Kui Hua , Tang Meng , Geng Ai Nong , Yu Hong Dong , Qin Hai Ying
Published: February 2011

By using virtual prototype technology, a model of Embedded Vane Rotary Compressor has been established for motion simulation. Based on theoretical analysis and simulation, the motion characteristic, forces and connection constraints was studied and analyzed. The results are helpful for improving the design and performance of the compressor.
Biocompatibility Research of Medicine Titanium Alloy Coating by Microarc Oxidation
Authors: Wang Feng Biao , Di Shi Chun , Yu Jie
Published: February 2011

A medicinal titanium alloy hydroxyapatite coating was fabricated by microarc oxidation process, and a kind standard of simulated body fluid was configured, after that the biocompatibility experiment was carried out. The soaked coatings surface morphologies were observed and analysed by scanning electron microscopy,and the coating spectra were simultaneityly researched by X-ray diffraction. The instance of degradation and precipitate were investigated,and the transformation of Ca/P value were measured.
The Static and Dynamic Characteristics Study of Aluminum Tank Semitrailer
Authors: Deng Ya Qiong , Wang Jin Gang , Wen Yi , Zhao Shuang , Dai Li Li
Published: February 2011

Taking an aluminum tank semitrailer as an example, this essay aim to analyze the strength and stiffness of the tank semitrailer and obtain stress and strain characteristics under different conditions on the basis of a finite element model, by using the finite element analysis software. By carrying on modal analysis in different work conditions, the essay gets the dynamic performance parameters of the tank. The results show that the tank fully meets the requirements of using, and the performance parameters of the tank will be foundation for the optimization.
The Definition and Solution to the Correlation in District Collaborative Design
Authors: Ma Jun
Published: February 2011

The district collaborative design is an advanced design organization mode. The problem of definition and expression of correlation in collaborative design is aimed. The organization characteristics are analyzed based on district collaborative design space. The connection relationship acyclic graph which includes connection semantics is achieved, and the relationship specialty and connection mode are explained. The algorithm is proposed to solve correlation for district collaborative design by use of correlation information model, and the correlation management model based on PDM is illustrated. Finally, a case study is conducted to prove these theory and method
Three-Dimensional Finite Element Analysis in Cutting Temperature for High Speed Milling of Titanium Alloys
Authors: Lin You Xi , Yan Cong Ming
Published: February 2011

A three dimensional fully thermal-mechanical coupled finite element model had been presented to simulate and analyze the cutting temperature for high speed milling of TiAl6V4 titanium alloy. The temperature distribution induced in the tool and the workpiece was predicted. The effects of the milling speed and radial depth of cut on the maximum cutting temperature in the tool was investigated. The results show that only a rising of temperature in the lamella of the machined surface is influenced by the milling heat. The maximum temperature in the tool increases with increasing radial depth of cut and milling speed which value is 310°C at a speed of 60 m/min and increases to 740°C at 400m/min. The maximum temperature is only effective on a concentrated area at the cutting edge and the location of the maximum temperature moves away from the tool tip for higher radial depths of milling. The predicted temperature distribution during the cutting process is consistent with the experimental results given in the literature. The results obtained from this study provide a fundamental understanding the process mechanics of HSM of titanium alloys.
Study on the Mechanism of the Impactor-Bit-Rock Interaction Using 3D FEM Analysis
Authors: Fan Yong Tao , Huang Zhi Qiang , Gao De Li , Li Qin , Zhu Hai Yan
Published: February 2011

To reveal the mechanism of the impactor-bit-rock interaction in geophysical prospecting percussion drilling, considering the coupling effect of the static pressure, impact force and rotary cutting, constructing the physical model of the impactor-bit-rock interaction, and using the finite element methods (FEM), three-dimensional (3D) model of the impactor-bit-rock interaction is established. Using the finite element analysis software (ANSYS/LS-DYNA), the 3D FEM analysis of the impactor-bit-rock interaction is carried out when compressed air pressure is 0.8 MPa, 0.9 MPa, 1.0 MPa, 1.1 MPa and 1.2 MPa respectively. The results show that: the energy transmission efficiency when piston impacts bit under different air pressure is not high and it should be improved further, bit can not fragment rock until it is impacted by piston, it is found that the best air pressure is 1.0 MPa when the impactor and bit are used to drill granite according to the volume of the fragmented rock and the depth of the crater, the speed and displacement on the radial direction of the piston which should be reduce even eliminate are very harmful. The results are further useful to extend the applications of the geophysical prospecting impactor and hammer bit.
Research on Lubrication and Wear-Resistant Mechanism of Ni60A/MoS2 Composite Coating
Authors: Zhao Yun Cai , Wang Li
Published: February 2011

The influence of MoS2 lubrication phase on the tribological properties of the Ni60A/MoS2 composite coating was conducted on UMT-2 micro-wear testing machine (USA), discussing the self-lubricating effect and mechanism. The result shows that with the increasing content of MoS2, the friction coefficient of the coating which changed with the increasing content of the MoS2 presents firstly decreases then increases, and the value reach the minimum when the quality percent of MoS2 wrapped with Nickel is 35%. Low-friction property of the Ni60A/MoS2 composite coating is due to the forming of MoS2 lubricating film in friction surface. The decreasing of the friction coefficient of the coating is in proportion to the coverage area of MoS2 lubricating film.
Error Analysis of Ladder Shaft Turning and the Research of NC Compensation
Authors: Li Jian , Luo Yong Chang , Nie Xiao Fan
Published: February 2011

To reduce the ladder axis machining error, in this paper, the finish turning of a machine tool spindle and the rough turning process is analyzed, were calculated the change of step-axis contour deformation in the process of the finish turning and rough turning with limited difference method and the finite element method (the elastic constraint and inelastic constraint in both ends ). Comparison of the deformation of the three profile, to find more realistic results, and simulate the spline of shaft ladder deformation, using Compensation method to process NC programming. To improve the processing quality of stepped shaft.
Limit Bearing Capacity Analysis of Structure System with Different Types of Element Using Elastic Modulus Reduction Method
Authors: Zhang Wei , Yang Lu Feng , Liu Li Wen
Published: February 2011

Limit bearing capacity analysis of structure system with different types of element (SSDE) is difficult to elastic modulus adjustment procedures. In this paper, elastic modulus reduction method (EMRM) is introduced for evaluation of the limit bearing capacity of SSDE, using the element bearing ratio (EBR) as the governing parameter. As a dimensionless quantity, the EBR can be used to measure the bearing state of every element, and the scheme of reducing elastic modulus can be expressed using a uniform equation for different types of element. When the structure system destroys, all elements will tend to reach their own strength. The algorithm is then extended to the plastic limit analysis of SSDE. Numerical examples are employed to demonstrate the applicability, accuracy and efficiency of the method.
Research on Classification Method of Multi-Circuit Pump Critical Parts Based on Fuzzy Theory
Authors: Sun Li , Li Tao , Yu Xiao Yang , Xie Ming Jun
Published: February 2011

This article designed a coding system DJBM-1of parts based on structural similarity. According to Fuzzy theory, the relationship between parts was determined quantitatively by mathematical methods, and threshold value λ was obtained through calculation. Objective classification was realized after initial classification and verification, avoiding the deficiencies of traditional classification method of parts and implementing the classification of parts effectively.
Theoretical Analysis of Designed Internal Forces of Jiamusi Highway Prestressed Concrete Bridge before Strengthening in China
Authors: Naser Ali Fadhil , Wang Zong Lin
Published: February 2011

The objective of this study is to calculate and analyze the internal forces under designed dead and live loads to evaluate the structural performance of corbels and T-shaped cantilever structure of the main span of Jiamusi highway prestressed concrete bridge to evaluate the state of the structural members of the bridge. Two software are used in this analysis. The first software is Dr. Bridge Ver. 2.95 which is used to analyze the internal forces of T-shaped cantilever structure under different load combinations. The second software is Ansys Ver. 10 which is used to analyze the internal forces in the corbel. The results of analysis show that at the dead load stage, the maximum compressive stress at the upper and bottom edge of all sections of T-shaped cantilever structure satisfies the allowable values of standard. The tensile stress doesn’t appear. At the normal service stage, there is enough reserve of compressive stress in the all sections, and the compressive stress is smaller than the allowable value of the standard. There is no tensile stress for all the controlled sections. The maximum main compressive stress and maximum main tensile stress of all controlled sections is smaller than the allowable value of standard. The bending strength of all sections satisfies the allowable values of standard, and there is big reserve of strength. The steel settled in the oblique section of 45° in the web of the corbel has enough reserve for the tensile strength. If the prestressed steel in the corbel is inefficient, the resistance of the oblique section given by the ordinary steel in the corbel and it can be resisted the loads. The longitudinal positive stress of vertical section a-b, vertical shear stress, main tension stress and main tension stress of oblique section a-c of 45 satisfy the allowable values of standard.
Study on the Mechanism of Improving the Formability of DP Steel LTWB at the Elevated Temperature Level
Authors: Guo Yu Qin , Chen Wei , Yang Xin
Published: February 2011

In the present work, warm tension tests for DP steel LTWB (B340/590DP) with 1.0mm/1.0mm thickness are performed on the CMT5205 universal tester, and its microstructure in the region adjacent to weld line is observed by the JSM-7001F scanning electron microscopy. Moreover, Imagetool software is applied to deal with the SEM photographs in order to study the influence of forming temperature on the martensite volume fraction, average length and thickness. By building the relationship of martensite structure volume fraction, feature size, configuration with macro-mechanical properties including stress peak, yield strength, elongation at failure and temperature, the mechanism of improving the formability of DP steel LTWB at the elevated temperature level is revealed, which is vital for optimizing the warm forming process parameters of DP steel LTWB and setting up the precise material constitutive model to enhance the FEM simulation accuracy.
Numerical Simulation of the Viscous Flow for the Supersonic Jet Element
Authors: Yu Yong , Zhang Guo Qing , Wang Fei
Published: February 2011

The viscous flow of the supersonic jet element was simulated numerically based on CFD technology, and many tests have been done to verify the numerical precision. The results show that the calculated data are good agreement with the experimental data. So the numerical simulation of the viscous flow for the supersonic jet element is accurate and reliable, and it can be applied to investigate the steady flow and unsteady flow in supersonic jet element.
Numeral Simulation of a New Forming Process: Stretch Forming Combined with Roll Forming
Authors: Hu Zhi Qing , Zhao Ji , Deng Yu Shan , Zhang Hao Han
Published: February 2011

In this study, the principle of the stretch forming combined with roll forming(SRF) is proposed, to present the availability of this process, it is simulated by the Method of Finite Element Analysis(FEA) by comparing traditional stretch forming(SF) with stretch roll forming (SRF), the result is shown that the roller covered the rubber rolling sheet metal is benefit to formed part, such as Von mises stress, the thickness thinned and the coincidence curve of formed part are studied.
Numerical Modelling of Shape Evolution of Tubular Preform in Spray Forming Process
Authors: Xiang Jin Zong , Zhang Yin , Fan Wen Jun , He You Duo
Published: February 2011

A three-dimensional mathematical model of growth, integrated with a new and effective algorithm for visibility checking, has been established based on a spray forming equipment with three different fixed atomizers in this paper. The model was used to predict the geometrical shape and the thickness profiles of the tubular deposit under various situations. By investigating and discussing the effects of different mandrel movement parameters and spray heights, the optimal atomizer of the equipment to fabricate a tubular preform was identified numerically.
Microstructures Development in Al-5Fe and Al-5Fe-3Y Alloys Solidified at Different Cooling Rate
Authors: Mi Guo Fa , Dong Cui Fen , Li Chang Yun , Wang Hai Yan
Published: February 2011

Cast, sub-rapidly solidified and rapidly solidified Al-5Fe alloy and Al-5Fe-3Y alloy were respectively prepared by vacuum melting, suction casting and melt spinning. The effect of increasing cooling rate and adding rare earth Y alloy on microstructures and phase composition were investigated. The results showed that the acicular Al3Fe phase transferred to spherical phase and dispersed secondary precipitations were also found when 3.0 wt% Y was added in the Al-5Fe alloy. Meanwhile, the microstructures were apparently refined by the increasing of cooling rate. The metastable phase A16Fe and intermetallic compound A110Fe2Y phase have been observed in Al-5Fe alloy and Al-5Fe-3Y alloy, respectively.
Design Milling Parameters Optimization System Based on Thin-Walled Parts
Authors: Mao Xin Hua , Hu Zhi Gang , Huang Ting Ting
Published: February 2011

Because of its low stiffness and intensity structural features, thin-walled parts affected by milling force, easily produce deformation and vibration among processing. In this paper, by optimizing milling parameters, it can be realized to control the size of the dynamic milling force and the milling state. Then it reaches the purpose to decrease workpiece deformation, and makes processing conditions maintain a stable. It not only reduces deformation caused by the vibration, but also makes thin-walled parts errors meet the tolerance requirements.
Analysis for Fracture Behavior of Compactor Grinding Tooth Forging Die Based on Finite Element Method
Authors: Shao Yong , Zhou Ji , Guo Ping Yi
Published: February 2011

For forging die fracture behaviors during the actual forging process of compactor grinding tooth, the fully forging process has been simulated based on FEM. Die stress changes and distributions were analyzed in details through two related simulation processes. The maximum load acting on the die which type is ideal rigid body predicted firstly. Then, the die stress can be obtained by the elastic-plastic analysis when the die bears maximum load. Results show that Local stress concentration beyond ultimate strength of material causes the fracture of lower die.
An Upper-Bound Analysis of Closed Multi-Ram Forging of Rod
Authors: Zhu Chun Dong , Fu Chen , Wang Hui
Published: February 2011

The shape of rod-shaped parts is complex, and the relative size changes more, so it is difficult to be deformed. Naturally the production of rod by closed multi-ram forging has many advantages. This paper introduces the analysis and calculation of the deformation load in auto rod pieces by closed multi-ram forging and the solve process of formula calculating deformation load of multi-ram forging, and then verified it by experiment. It has been shown that upper-bound analysis method is accurate in calculating the deformation load of multi-ram forging, and it can be used as the basis of the selection of presses and calculating the deformation load.
Numerical Simulation and Experimental Study of Limit Drawing Ratio of Steel Sheets
Authors: Chen Ji Ping , Qian Jian Qing , Li Sheng Zhi
Published: February 2011

The limit drawing ratios of the steel sheets are studied by the numerical simulation using the finite element software PAM-STAMP 2G. The limit drawing ratios of the steel sheets are also measured by the practical Swift cup test. The results of the experiments and the simulations are compared and analyzed. The results show that the overall shapes of the deep drawing parts of the experiment and the simulation are roughly the same. The maximum deviation of limit drawing ratio values between the experimental results and the simulations for two steel sheets with various thicknesses is only 2.2%. The deviation of limit drawing ratio of steel sheet obtained through PAM-STAMP FEM software is small. The PAM-STAMP software is highly reliable for the steel sheet deep drawing simulation.
Influence of Cross Section Shapes of Preformed Blade Body for Final Forging Formability Based on Numerical Simulation
Authors: Shao Yong , Guo Ping Yi , Liu Zhi An , Zhou Zhao Yu , Cai Wei
Published: February 2011

During the preform design of blade body, the final forging process for blade body with different transverse cross section shapes coupled different twist angles along blade body are simulated by using DEFORM-2D finite element analysis software. The final forging quality effected by different perform structures of blade body are analyzed in details through comparing some key factors such as formability, deformation uniformity, loss of heat before deformation. The valuable references are obtained for further design of optimizing blade body shape.
The Model of Thermal Deformation Resistance for P20 Steel
Authors: Zhang Shun Hu , Gao Cai Ru , Wu Hui Liang , Wang An Yang , Zhao De Wen
Published: February 2011

In this paper, single-pass compression test of P20 steel was carried out using thermal simulation and the experimental curves of deformation resistance were determined. Through analyzing the curves, the type of deformation resistance under practical production conditions was determined. Furthermore, the model of deformation resistance of P20 was obtained by the method of regression means, and the model precision was analyzed with the method of mathematical statistic analysis. The results indicate that the model has high accuracy in predicting precision.
Analysis and Control of Car Door Inner Panel Forming Fracture Based on Experience Knowledge and Numerical Simulation
Authors: Wu Hua Ying , Guo Chen , Xiao Chun Hui
Published: February 2011

The process factors influencing the forming quality of car inner door panel such as stamping direction, binder surface, draw-bead, addendum surface and technical cut are determined based on experience knowledge. Aiming at local fracture problem of test pieces, some key parameters are determined based on experience knowledge, and the strain in thinning area of sheet metal forming is analyzed by numerical simulation. Based on this, process optimization and die modification scheme are put forward. Engineering inspection proved that optimized process and die parameters are reasonable, after increasing die fillet radius and process hole radius, decreasing draw-bead height, qualified products are achieved and fracture flaw is well controlled.
PSO Algorithm Based Task Allocation in Dynamic Virtual Enterprise
Authors: Jiang Jian Hua , Sheng Bu Yun , Gong Li Xiong , Yang Ming Zhong
Published: February 2011

To solve the order task allocation in Dynamic Virtual Enterprise (DVE), a multi-goal decision-making model was constructed. As to the model, an improved Particle Swarm Optimization (PSO) algorithm based order task allocation method was presented on the basis of analyzing the traditional PSO algorithm. The method overcome the deficiencies of prematurely and trapped into local optimal solution easily in traditional PSO by adjusting the parameters in algorithm automatically and introducing mutation operation from genetic algorithm. And the TOPSIS based computing method of particle fitness value was researched. Finally, the feasibility of the method was verified by an application example.
Effect of Drive Roll Rotation Speed on Ring Rolling Process
Authors: Zhou Jie , Gong Xiao Tao , Yang Xiao Bing , Xu Wu Jiao
Published: February 2011

Based on the platform ABAQUS, 3-D FEA model for ring rolling has been constructed to investigate the effect of drive roll rotation speed on the metal flow in the ring rolling process. It can be seen clearly that the axial metal flow in the outside diameter of the rolled ring increases with the increasing of drive roll rotation speed and with the decreasing of the feeding magnitude per revolution , which causes the increasing of fishtail coefficient FT and maximum spread coefficient and in turn makes the quality deterioration of end-plane in the rolled ring. The rolling force and rolling torque necessary to execute the rolling process are reduced when the drive roll rotation speed is elevated, which results in the lower requirement for the characteristic of force and energy in the rolling machine. Besides that, average equivalent plastic strain PEEQ also increases, which indicates the enhancement of plastic deformation and is beneficial to the improvement of the mechanical property of the formed ring. But one point that we should pay attention is that uneven deformation and possibility of the inner defects in the rolled ring might be increased with the increasing of the drive roll rotation speed.
Study on the Large Module Spur Gear Cold Forming Process by Means of Numerical Simulation
Authors: Li Qian , Bian Yi , Zhong Zhi Ping , Liu Gui Hua , Chen Ying
Published: February 2011

The cold forging process of large module spur gear with four modules and 59mm breadth is performed by means of numerical simulation method. Two processes to forming such spur gears were compared by the simulation method, one is with the closed-die performing and extrusion in the finish-forging, the other is with divided-flow method in the finish-forging. Especially, the divided-flow method is analyzed in detail. The necessary reference and basis to realize practical cold precision forging process of spur gear with large modulus is provided eventually.