bluuebunny/crossref_metadata_2025 huggingface dataset:
Punch Die of 385 Diesel Part Design Based on CAE Technology
Authors: Zhou Jian , Li Li Jun , Yan Yong Lin , Zhou Dong Cheng , Cheng Ke
Published: February 2011

For getting the higher quality,the paper analyses the punching order according to the part shape,then determines the die styles.The dies include blanking and bending steps,the bending dies are choosed carefully,from the part to its’extension size,then to cavity size and punch size,thus the general assembly drawing is tested whether it is right.
Nickel-Diamond Compound Electroless Plating on Cast Aluminum Alloys
Authors: Huang Yuan Sheng
Published: February 2011

In order to improve both the hardness and the erosion resistance of cast aluminum alloys, nickel-diamond compound coatings were deposited on the alloys by a compound electroless plating process. The morphology, phase structure, hardness, erosion resistance and adhesion of the electroless coating were investigated. The results show that the pretreatment such as removing the silicon in the surface of the alloys, zinc dipping, alkali electroless nickel is necessary. The deposition of an electroless nickel coating without diamond prior to nickel-diamond electroless plating can improves the erosion resistance. A best nickel-diamond compound electroless plating process is found. The hardness of the nickel-diamond compound coating reaches 730 HV. Both the adhesion and erosion resistance of the compound coatings are very good.
Finite Element Analysis of Bulging Forming for Sheet Metal with Bottom Compression Drawing Method
Authors: Lin Qi Quan , Dong Wen Zheng , Xiao Hui , Wang Zhi Gang
Published: February 2011

For the bulging forming of sheet metal industry, two of the major disadvantages are large punch load and short bulging height, generally referring to the traditional process. In this present work, a new processing technique had been introduced for bulging forming based on bottom compression drawing method. The finite element method (FEM) with DEFORM-2D was used to investigate the bulging process. Besides, the mechanism of dimple defect occurred in bulging process was analysed with numerical simulation. The results showed that the dimple defect divided into four stages in the bulging process, where revealed an inverted cone-shape at the bottom part of the centre workpiece. Moreover, the laboratory experiments were carried out to validate the results of numerical simulation, which showed a good agreement with the FEM simulation results.
Thickness Indirect Measurement Method for Direct Pulling Pilot Cold Rolling Mill
Authors: Jiao Zhi Jie , He Chun Yu , Li Jian Ping , Liu Xiang Hua
Published: February 2011

Pilot cold rolling mill is the important tool for the cold rolling process researching and new steel grade development. According to the design of the new type direct pulling pilot cold rolling mill, based on the mass flow constant principle, strip exit thickness indirect measurement method is studied. During rolling, strip entry and exit speed can be calculated accurately according to the measured value of two sides’ clamps movement. Data filtering treatment is adopted and program flow chart is designed. Based on the material entry thickness measured manually, exit thickness of all passes can be measured indirectly. This thickness indirect measurement method has been applied successfully on the new type pilot cold rolling mill, and the measurement results show that this method has a good accuracy.
The Investigation of Multi-Stage Sheet Metal Stamping Process for Deep Drawing
Authors: Chen Wei , Pan Ke , Wu Ming Yan , Huang Zhong Fu , Dai Feng Ze
Published: February 2011

Based on empirical analysis and FEA modeling of multi-stage sheet metal stamping, the optimal sheet metal stamping process can be supplied. Concurrently, the effects of process parameters on formability are found by numerical simulation. Taking an example of deep drawing part, the results got from the numerical simulation are compared with experimental results, which proves that finite element analysis (FEA) is effective and accurate in optimizing the process design of multi-stage sheet metal progressive stamping.
Study on Regulation of Rotation Speeds and Tangent Slip in Radial-Axial Ring Rolling Process
Authors: Wang Qiang , Wu Qian , Zhang Xian Ke
Published: February 2011

Radial-axial ring rolling is a process widely used to produce large precise seamless rings. The regulation of rotation speeds between main roll and axial rolls and tangential slip between main roll and ring influence greatly the rolling process. In this paper, an equation governing regulation of rotation speeds is derived. Influences to rotation speeds from conic angle and contact position are analyzed. Equation of relative tangential slip speeds in both inner and outer diameters are established, which are employed to creat a condition of non tangential slip in radial-axial ring rolling process.
Preparation and Characteristics of Expanded Graphite
Authors: Yang Yan Feng , Zhang Xue Jun , Xu Xiao
Published: February 2011

Expanded graphite (EG) was prepared using fine flake graphite that could go through 50 mesh as raw material, perchloric acid as inserting agent and concentrated nitric acid as oxidant. The effects of amount of raw materials, reaction time and reaction temperature on expanded volume and sorption capacity of EG were studied, and microstructure of EG were characterized by X-ray diffraction patterns and scanning electron microscope. The results show the best process conditions are as follows: m(flake graphite):m(perchloric acid):m(concentrated nitric acid)=1:6:0.18, the reaction time is 50 min and the reaction temperature is 35°C. The reaction condition is moderate and is controlled easily. The sorption capacity of EG will increase almost linearly with increase of expanded volume. The largest expanded volume and sorption capacity of EG are 241 ml/g and 89g/g, respectively, when the expanding temperature is 800°C.
Analysis of Draw Bead Geometry on Wall Thinning and Concave/Convex Feature in Rectangular Deep Drawn Parts
Authors: Phanitwong Wiriyakorn , Thipprakmas Sutasn
Published: February 2011

The application of the draw bead could reduce the concave/convex wall features. However, it also affected the wall thinning. Therefore, it is difficult to determine the suitable draw bead geometry to obtain a straight wall without the wall thinning. In this study, the effects of draw bead geometry of height and width on concave/convex wall feature and wall thinning were investigated by using the finite element method (FEM) and experiments. Based on the stress distribution analysis, the increasing in draw bead width and the decreasing in draw bead height lead to the concave wall feature increased; however, the application of the too small draw bead width and the too large draw bead height generated the convex wall feature. The wall thinning also decreased as the draw bead width increased as well as the draw bead height decreased. Therefore, the application of suitable draw bead height and width significantly suppressed the concave/convex wall feature and wall thinning, which resulted in the straight wall with the smallest wall thinning could be achieved.
Design of Drawing Compound Die for Side Hole Part
Authors: Nie Fu Rong , Li Hong Wei , Tian Fei , Yang Li Li
Published: February 2011

Based on the side hole and no flange and one-step drawing part forming analysis and comparison of the process, the compound die that can complete 4 procedures -blanking, drawing , punching and trimming at in the same forming-position was synchronously designed. Production testing confirmed that there were different levels of improvements in the product quality, production efficiency and economic efficiency. This paper describes die structure, die working process, design and manufacture of main pans of die.
Novel Carbon Source in Manufacture of LiFePO4/C
Authors: Liu Yu Wen , Zhang Wei , Wang Hong Mei , Jiang Jing Na , Sun Bin
Published: February 2011

LiFePO4/C composite materials were synthesized by a solid-state method. The carbon source was selected from glucose, cauric acid, cinnamic acid and PVA and the influence of different carbon sources on the performances of LiFePO4/C was investigated. The crystal structure, morphology and electrochemica1 properties of LiFePO4/C were analyzed by XRD, SEM and galvano static charge-discharge method. The results show that the materials have olivine structure and that the LiFePO4 material coated with carbon gives enhanced performance in terms of practical capacity and cycleability of the cell with lithium metal piece as an anode. The specimen used PVA as the carbon source has a fine and uniform particle size and shows excellent electrochemical performances. The first discharge capacity is up to 147.5 mAh•g-1 at 0.1C rate, and after 20 times of cycling the discharge capacity is still 144.7 mAh•g-1.
Research on Ball Spinning Forming of Superalloy Inconel 718 Thin-Walled Tube
Authors: Li Yong Hua , Fan Tao , Zhang Ning
Published: February 2011

Ball spinning is an effective process to manufacture thin-walled tubular product of superalloy Inconel 718, which has been used widely in aerospace and other fields. In this literature, ball spinning process of superalloy thin-walled tube was investigated using software DEFORM. The build-up phenomenon and its influencing factors like principal axis speed, axial feed rate and wall thichness reduction were investigated using the finite element method (FEM). The experiment of ball spinning process was perfomed based on the proper technical parameters obtained by simulation. The simulated results agreed well with the experimental results.
An Artificial Immune Algorithm Based Intelligent Monitoring System in Grinding Process
Authors: Lv Zhi Jun , Xiang Qian , Pang Jing Zhu
Published: February 2011

Grinding is widely used as a precision process for machining difficult-to-cut materials. Grinding productivity is still greatly dependent on the experience and skill of human operators. Focusing on the indirect method, an attempt was made to build up an intelligent system to monitor the condition of grinding wheels with force signals and the acoustic emission (AE) signals. An artificial immune algorithm based multi-signals processing method was presented in this paper. The intelligent system is capable of incremental supervised learning of grinding conditions and quickly pattern recognition, and can continually improve the monitoring precision. The experiment indicates that the accuracy of condition identification is about 87%, and able to meet the industrial need on the whole.
Effect of Geometry Parameters on Cross-Sectional Distortion of Thin-Walled Rectangular Tube in Rotary-Draw Bending Process
Authors: Liu Yu Li , Zhao Gang Yao , Zhang Jin , Yang He
Published: February 2011

In rotary-draw bending process of thin-walled rectangular tube, cross-sectional distortion is an unwanted byproduct, which is closely related to geometry parameters. To study the effects of geometry parameters on cross-sectional distortion, a 3-D finite-elements model was built under the ABAQUS/Explicit environment, and its reliability was validated by experiments. Then, simulation and analysis of the influence laws of geometrical parameters on cross-sectional deformation degree were carried out. The results show that increases with the increase of b/h and decreases with the increase of R/h when b/h>1. However, R/h has little influence on δh when b/h≤1. And the influence of b on δh is larger than that of h, and the effect of h on δh is larger than that of R.
The Study of Parameters on CK67 Steel Sheet Spring-Back in L-Dies Bending Processes
Authors: Bazrafshan J. , Gorji A. , Armaky A. Taghizadeh , Sadeghi J.
Published: February 2011

One of the most sensitive features of sheet metal forming processes is the elastic recovery during unloading, called spring-back, which leads to some geometric changes in the product. This phenomenon will affect bend angle and bend curvature, and can be influenced by various factors. In this research, the effects of sheet thickness and die radiuses on spring-back in L-die bending of CK67 and St 14 steel sheet were studied by experiments and numerical simulations.
Effects of Preform on Thickness Distribution of Hydroformed Y-Shaped Tube
Authors: Liu Gang , Peng Jun Yang , Wang Xiao Song , Zhu Shi Qiang , Yuan Shi Jian
Published: February 2011

Hydroforming processes of a Y-shaped stainless steel tube with d/t (ratio of diameter to thickness) of 183 is presented. FEM simulations were carried out for analyzing the stress states and thickness distribution in the workpieces during hydroforming of the Y-shaped tube. A two-step process with preform procedure is presented to improve the stress states in the protrusion and to avoid the severe thinning at the top of the protrusion. Through the two-step hydroforming, the wrinkling and cracking defects were all avoided and sound components were produced.
The Experimental Study on the Microstructure of SS400 Steel with Traveling Magnetic Induced Rapid Tempering Process
Authors: Li Hui Qin , Chen Zheng Zong , Ma Yong Lin , Xing Shu Qing
Published: February 2011

The purpose of this experiment is to find the effects on structures and cementite of rapid induced heating and tempering. The author designed a travelling magnetic field device, using a frequency conversion power supplier, the well prepared SS400 plates were heated, and some parameters are investigated through changing their values (frequency, current, gap from the pole surface to the steel plate and heating time). The temperatures during the heating process are recorded continuously. Meanwhile, the structures and hardness are investigated. The results show that the heating temperature affected the structure and the low temperature impact energy of the steel, at a suitable process parameters combining, the size and morphology of the separation and precipitation particles are very fine and distributed uniformity inside grains.
Effect of Severe Plastic Deformation on the Characteristics of a PM Aluminum Alloy
Authors: Grande Marco Actis , Bidulský Róbert , Bidulská Jana , Kvačkaj Tibor
Published: February 2011

The paper deals with the influence of severe plastic deformation on the typical powder metallurgy (PM) microstructural characteristics, such as porosity, of a PM aluminum alloy. A commercial ready-to-press aluminum based powder was used as material to be investigated. After applying different compacting pressures (400, 500, 600 and 700 MPa), specimens were debinded in a ventilated furnace at 400 °C for 60 min. Sintering was carried out in a vacuum furnace at 610 °C for 30 min. The specimens were ECAPed for 1 pass. The dimensional and morphological porosity of investigated materials were measured individually for each pore. Results show that ECAP generates shearing stress breaking down the oxide film; this, coupled to particles deformation under local constraints, enables strong bonding and stability. Therefore, ECAP supports next progressive decreasing of pore size as well as strongly influences both dimensional and morphological porosity characteristics, considering that small pores evolve easily to a circular form. Moreover, ECAP cause strong bonding between adjacent particles, which results in a significant increase of mechanical properties.
The System Design of Spiral Drum Based on Parameterized Modules
Authors: Zhao Hong Mei , Su Dan , Shao Zhi Mei , Li Hong Gang
Published: February 2011

In order to make the spiral drum has a good performance and human-computer interaction function. This paper made the spiral drum module division base on the modularization theory and parametric design. Built the 3 D parametric model of spiral drum by Pro / E software, completed the assembly of spiral drum parts, and analyzed the interference of each component, consequently, improved the accuracy of the design. It also can made parametric driving for relative modular as user different needs for spiral drum design. namely, it can got the 3-D model and assembly drawing, and can achieve the goal of improving the drum design efficiency.
A Study on Dynamic Recrystallization Behaviours of AZ80 Magnesium Alloy
Authors: Yang Ming , Yang Yong Shun , Yang Dong Dong
Published: February 2011

Using the compression tests on a Gleeble-1500 thermo-mechanical simulator to study the dynamic recrystallization behaviours of AZ80 magnesium alloy in the temperature range of 593-683K and strain rate range of 0.01-10s-1. By the analysis of the dynamic recrystallization kinetics, the Avrami exponent (m) and the constant (k) have been determined, and they aren’t constant and depend on the dimensionless parameter(Z/A).
Microstructure and Properties of Fe–Al/Cr3C2RE Composite Coating Produced by HVFS
Authors: Liu Xiao Ming , Dong Jun Hui , Xu Run Sheng
Published: February 2011

Fe–Al/Cr3C2composite coatings produced from high-velocity flame spraying (HVFS) are Fe–Al intermetallic composite coatings with remarkable room-temperature and high-temperature properties. However, Fe–Al/Cr3C2composite coatings have a Cr3C2content of 50%. This causes the coatings to become porous and limits its room-temperature and high-temperature properties. In order to improve microstructure and properties of Fe–Al/Cr3C2composite coatings, Fe–Al/Cr3C2RE, including Fe–Al/Cr3C2and CeO2, is sprayed by HVFS technology onto AISI 1020 steel. The properties including bonding strength and high-temperature corrosion-resistance of Fe–Al/Cr3C2RE composite coating are tested at 25°C and 650 °C. For comparison, two other materials, substrate AISI 1020 steel and Fe–Al/Cr3C2composite coating, are tested under the same experimental conditions. The microstructures of the coatings are analyzed by scanning electronic microscopy (SEM), the cross-section morphology of Fe–Al/Cr3C2RE composite coating is analyzed by energy-dispersive spectroscopy (EDS), and the existing states of oxides are analyzed by transmission electron microscopy (TEM). The phases of the composite coating after corrosion are analyzed by X-ray diffraction (XRD). The results demonstrate that the properties of Fe–Al/Cr3C2RE composite coatings is better than that of either AISI 1020 steel or the Fe–Al/Cr3C2composite coating. CeO2is a surface-active agent, and it significantly improves the microstructure and properties of Fe–Al/Cr3C2RE composite coating. CeO2improves the bonding strength of Fe–Al/Cr3C2RE composite coating by reducing the surface tension of droplet and enhancing its fluidity as well as wetting capacity on the surface of the substrate, decreasing the internal stress of coating.Adding CeO2to the coating produces Al2O3and Cr2O3oxide films, which protect the substrate AISI 1020 steel from corrosion more efficiently.
Study on Metallography and Properties of WC Cast-Infiltration on Carbon Steel Surface by Expendable Pattern Casting
Authors: Gao Hong Xia , Zhang Yu Hui , Liu Jian Xiu , Yang Gai Yun
Published: February 2011

With expendable pattern casting, WC infiltrated layer on carbon steel surface can be gained. Metallography of infiltrated layer was researched, hardness of infiltrated layer was tested and wear resistance was also tested on ML－100 attrition testing machine. Experimental results shoes that: microstructure of infiltrated layer is made up of pearlite, ferrite and WC particle, Brinell hardness of infiltrated layer is 1.7 times that of the matrix and wear resistance is 2.97 times that of the matrix.
An Investigation on Effect of Residual Stress on Springback Behavior of High Strength Steel in U-Bending Process
Authors: Lawanwong Komgrit
Published: February 2011

Bending process is an important process in the metal sheet forming in many industries. The main problem of the bending process is the spring-back phenomenon after removing the punch. This research aims the investigation on effect of residual stress on springback behavior of sheet metal in U bending process. The corner setting technique and bottoming process were designed for experiments. The corner setting technique and bottoming has reduced the thickness in bending area to 5, 10, 15 and 20 percent of the original sheet thickness. Clearance between punch and die of both processes was equal to same the thickness. The residual stress value and springback phenomenal were investigated by commercial program code DEFORM 2D which was able to analyze the effect stress and force in bending area. Electrolytic zinc coated carbon steel grade JIS; SECC, JIS; 440 and JIS; 590 which having the thickness of 1 mm were employed as the workpiece material for all experiments. The result of three materials in conventional U bending die shows larger spring back than the corner setting technique and bottoming process. Moreover, the corner setting technique reduces spring back value in bending process but requires high bending force. Corner setting technique and bottoming process at 15% and 20% shows that the spring go of all parts. The FEM simulation results explained the effect of residual stress to springback phenomenal. Comparisons between experimental and finite element method results were also performed.
Numerical Simulation of Deep-Drawing Processes of Square Cup under Bilateral Constrained Conditions
Authors: Xiao Xiao Ting , Huang Li Cheng , Liao Yi Juan , Tan Li Guang , Chen Qiao Yu
Published: February 2011

In this paper, the flow rule of metal during the deep drawing of the non-symmetry workpieces was investigated by means of the numerical simulation of deep-drawing processes of square cup under bilateral constrained conditions. The numerical simulation was carried out by advanced analysis software Dynaform5.5. SUS304 stainless steel was used as the deforming materials. The influence of different friction coefficient and blank holder force on the drawing forming quality was analyzed. The results showed that the material flow in different areas has different trends with increase of friction coefficient and blank holder force.
CAD Software Development for the Continuous Flexible Forming Process
Authors: Liu Lin , Cai Zhong Yi , Wang Shao Hui , Li Mine Zhe
Published: February 2011

The software for the continuous flexible forming process was developed using Visual C++ platform. It can directly read the triangular mesh data of the CAD model. The three-dimensional model was reconstructed rapidly by using the core function of the OpenGL. Moreover, the mathematical model of adjusting the flexible rolls and the longitudinal curvature were established by this software. Using these mathematical descriptions the simulation of the continuous flexible forming process can be finished from the viewpoint of geometry.
Numerical Simulation and Verification of Multi-Operation Sheet Forming Process for Stamping Parts of Spiral Step Surface
Authors: Sun Ling , Xing Jian Wei , Cheng Wu Hua
Published: February 2011

On the basis of in-depth simulation analysis of stress and strain, thickness and forming limit changes in the property sphere during the drawing process for the stamping part of the spiral step surface, combined with the comprehensive simulation analysis of flanging, punching and other operations for the parts, it is concluded that the most obvious non-uniform changes of sheet thickness occur in the drawing process and then in the flanging process. The possibility and the distribution of tension fracture in ironing and wrinkles in thickening has been predicted and the production feasibility of low-cost drawing process without the blank holder and multi-operation forming process for stamping parts of spiral step surface. The validity of multi-operation numerical simulation results has been verified by the actual measurement of finished product rate and product thickness in trial production.
The Measurement for the Effective Anisotropy Constant of the Nanocomposite Permanent Magnetic Material Nd2Fe14B/α-Fe
Authors: Zhang Zhan Xin , Li Hui Li , Liu Tao , Wang Feng Ming
Published: February 2011

The effective anisotropy constant and the saturation magnetization in nano composite Nd2Fe14B/α-Fe have been calculated by the law of approach to saturation (LATS) method. The applicability of the method has been analyzed. The calculated result shows that the LATS method is suitable for the calculation of the effective anisotropy constant and the saturation magnetization in nano composite permanent magnetic materials.
Study on Springback Compensation in Multi-Point Forming
Authors: Zhang Qing Fang , Cai Zhong Yi , Li Ming Zhe
Published: February 2011

Springback compensation of Multi-point forming (MPF) was analyzed in the paper based on the ideal elastic-plasticity and linear hardening material models. The calculation formulas for adjusting radius of MPF die, both single-curvature and double-curvature, were obtained. Cylinder and spherical surfaces were formed by MPF equipment. Experimental results show that the errors between formed surface and target shape are within 5%. Moreover, when using formulas derived from linear hardening model, it is found that the formed surface is more close to target contour, and the presented formula can be used to determine the adjusting radius of MPF die in practice.
Development of Visualization System for Aircraft Assembling Process Oriented Assembly Field
Authors: Qu Li Gang , Zheng Shuang , Guo Hong Jie
Published: February 2011

The technologically system architecture of aircraft assembling process visualization is presented according to the development requirement of digital aircraft assembly. The key technologies is studied about the dynamic data associating form EBOM to PBOM, simulatiing and optimizing assembling process based on DELMIA, and lightening the 3D models, which are the technological foundation to implementation of building the assembly resource database, designing the assembly process planning, visualizing assembling process and informations. The visualization system for aircraft assembly simulation is developed and built based on C/S networked mode, which could be applied in aircraft assembly workshop. The system platform is industrially test taken the forward cargo door of one civil aircraft for example, it is proved that this visualization system could be applied in aircraft assembly field as guidance of assembling production, the accuracy and the efficiency of parts and components' assembly are improved distinctly.
A New Type Multi-Mode Linear Ultrasonic Motor
Authors: Zhang Tie Min , Ping Luo , Li Liang
Published: February 2011

A prototype for multi-mode linear ultrasonic motor has been proposed and designed. It is designed using a combination of the first longitudinal and the first bending mode. The piezoelectric ceramics convert energy using the longitudinal d33 effect which allows an improved reliability, large vibration amplitudes and excellent piezoelectric coupling. The normal direction motion of the driving element is excited by the first longitudinal mode. The tangential direction motion of the driving element is excited by the first bending mode. The resulting displacement of the driving element is transmitted by the frictional force between the vibrator and the rail in a linear motion. The analysis on the modals of the composite vibrator by using the ANSYS finite element software has been presented in this paper. Finally, the vibrator structure of the motor and the motor's own structures are designed. The basic design is discussed and simulations are compared with the experimental results, the results show that the motor characteristics can be optimized for a particular task by choosing the appropriate operating parameters such as exciting voltage, exciting frequency and normal force.
Effect of the Thickness Ratio on the Failure Modes of Tailor Welded Blanks
Authors: Chen Shui Sheng , Lin Jian Pin , Liu Jing
Published: February 2011

Tailor welded blanks (TWBs) offer several notable benefits including decreased part weight, reduced manufacturing costs, increased environmental friendliness, and improved dimensional consistency. To take full advantage of these benefits, however, one needs to overcome the reduced formability of TWBs and be able to accurately predict the failure modes depending on the thickness ratio between the thicker and thinner sheets of a tailor welded blank with similar base materials early in the design process. In this paper, we studied the effect of the thickness ratio on the limit dome height of TWBs by using finite element method and experiments, analyzed the effect of TR on the failure mode of TWBs. A concept of the critical thickness ratio was presented to predict the failure modes of TWBs. The results show that the rapture originates on the weld of TWBs when the thickness ratio is less than the critical thickness ratio and on the thinner side when the thickness ratio exceeds the critical thickness ratio.
Thickness Demarcation Circle of Double-Cone Tube during Hydroforming
Authors: Yuan Wen Jing , Liu Xiao Hang , Tian Hao Bin , Wang Xiao Song , Yuan Shi Jian
Published: February 2011

The analytic formula of the thickness demarcation circle during hydroforming of double-cone tube is derived by using the mechanical analysis and the total strain theory. The effect of friction coefficient, expansion coefficient, ratio of axial stress to internal pressure, length of feeding zone, and initial thickness of tube on the thickness distribution can be given by this formula quantitatively, and the analytic results were compared with the FEM analysis and experimental results. The results show that with the increasing of friction coefficient, the ratio of axial stress to internal pressure, the relative length of feeding zone, the distance between thickness demarcation circle and tube end decreased, that means the increasing of length of the thinning zone, and with the increasing of relative thickness of tube blank, the distance between thickness demarcation circle and tube end increased, that means decreasing of length of the thinning zone.
Analysis of Strip Shape in Cold Rolling of Thin Strip
Authors: Jiang Zheng Yi
Published: February 2011

In this paper, finite element models of the strip shape during cold rolling of thin strip in both symmetrical and asymmetrical rolling cases have been successfully developed, and the effects of rolling parameters on strip shape such as the thickness distribution along the strip width have been obtained. The strip edge drop and shape are discussed under both symmetrical and asymmetrical rolling conditions. Simulation results show that the asymmetrical rolling can reduce the strip edge drop dramatically, which is useful in improving the strip shape and reducing the energy cost during cold rolling of thin strip. The developed finite element model has been verified with the experimental value. The obtained results are applicable to control the rolled thin strip shape in practice.
Cell Direct Assembly Technology Adopting Hybrid of Gelatin-Based Hydrogels
Authors: Liu Hai Xia , Li Sheng Jie , Yan Yong Nian
Published: February 2011

Through analyzing cell direct assembly process requirements and existing hydrogel materials properties, employing the discrete/deposit rapid prototyping technique, developed a cell direct assembly technology adopting the hybrid of gelatin-based hydrogels. The cell assembly technology skillfully combined with the sol/gel transition mechanism about chemical and physical crosslink of gelatin-based hydrogels, in consideration of the main forming factors, through controlling the extruded materials rheological properties and optimizing the forming process, thereby achieved a promising assembling process with high cell survival rate and its corresponding biological viability. The technology can form a predefined three-dimensional structure with certain shape and size, suitable for variety of natural polymer materials (the most similar with extracellular matrix, such as fibrin, sodium alginate, chitosan, hyaluronic acid) with gelatin coupling forming; therefore, it satisfied majority cells needs of choosing the gelatin-based composite hydrogels reasonably. With the limitative extrusion pressure, more than 90% of the cells survived through this process and performed metabolic functions during a long term culture. This technology is a front research of biotechnology manufacturing science, is an important expansion of manufacturing technology.
Investigation of High Strength Steel for Automotive Roll-Forming Parts
Authors: Yan Pei Jie , Han Jing Tao , Jiang Zheng Yi , Li Hei Jie , Liu Li Xian
Published: February 2011

In recent years, the number of automobiles has been steadily increasing, which has significantly impacted on the society and human life, and led to many social problems such as fuel crisis, environment pollution. Therefore, lightweight designing becomes a focused issue. Lightweight materials application, optimized structure design and advanced manufacturing process are the main ways to achieve the lightweight. However, low plasticity and ductility of high strength steel constrain the application of high strength steel. In this paper, the basic principle of roll forming for automotive parts is investigated, and it is innovatively applied in the hot roll forming process of the ultra high strength steel.
Influence of Operation Conditions and Ambient Temperature on Performance of Gas Turbine Power Plant
Authors: Rahman M.M. , Ibrahim Thamir K. , Kadirgama K. , Mamat R. , Bakar Rosli A.
Published: February 2011

This paper presents the effect of ambient temperature and operation conditions (compression ratio, turbine inlet temperature, air to fuel ratio and efficiency of compressor and turbine) on the performance of gas turbine power plant. The computational model was developed utilizing the MATLAB codes. Turbine work found to be decreases as ambient temperature increases as well as the thermal efficiency decreases. It can be seen that the thermal efficiency increases linearly with increases of compression ratio while decreases of ambient temperature. The specific fuel consumption increases with increases of ambient temperature and lower turbine inlet temperature. The effect of variation of SFC is more significance at higher ambient temperature than lower temperature. It is observed that the thermal efficiency linearly increases at lower compressor ratio as well as higher turbine inlet temperature until certain value of compression ratio. The variation of thermal efficiency is more significance at higher compression ratio and lower turbine inlet temperature. Even though at lower turbine inlet temperature is decrement the thermal efficiency dramatically and the SFC decreases linearly with increases of compression ratio and turbine inlet temperature at lower range until certain value then increases dramatically for lower turbine inlet temperature.
Investigation of Airflow Field in Grinding Zone Based on FLUENT
Authors: Xiu Shi Chao , Di Jun , Pei Shao Yong
Published: February 2011

It is necessary to supply enough grinding fluid during grinding process to lower grinding temperature. But, there is little grinding fluid into the contact area actually due to the airflow layer with high pressure around grinding wheel. In this paper, the finite element analysis and simulation on airflow field in the grinding zone is performed based on hydrodynamics. The performance and the influencing mechanism of the airflow field on effective grinding fluid are analyzed further. The research works show that it is important to design the grinding wheel and fluid jet parameters reasonably for increasing the proportion of effective grinding fluid.
Experimental Research on the Dry Electrostatic Cooling Assisted Machining for Hardened Steel
Authors: Liu Xin , Xu Wen Ji , Sun Jing
Published: February 2011

Dry electrostatic cooling (DESC) assisted machining is one of the green machining technologies that uses ionized air flow as lubricating and cooling medium in the machining process. The influence of discharge parameters on the efficiency of ion transport and ozone concentration in the DESC is experimentally researched. The results show that the efficiency of ion transport increases with the rising of the discharge current and air pressure, but decreases with the rising of the distance from the nozzle and the nozzle diameter. The tungsten electrode is used to obtain high ozone concentration with the nozzle diameter of 2-4mm, air pressure of 0.2-0.4MPa, and the distance from the nozzle within 0.5mm. Experimental research on the DESC assisted machining for hardened steel GCr15 shows that cutting force decreases by 7%-28%, tool wear reduces by 30-50%, and tool life is 1.5-3.3 times more than dry cutting. Better results are achieved when increasing the cutting speed.
Tool-Path Generation for Conical Groove of Cylindrical Cams by Small-Sized Cutting Tools
Authors: Hung Jui Pin , Chiu Kuan Lin , Lai Yuan Lung
Published: February 2011

Instead of 2D expanding diagram method, this paper presents a new regenerating method for cutter location paths of using smaller tools to produce cylindrical cams. According to the expected motions, cams are put to use in various applications in mechanism. For a cylindrical cam, the roller follower operates in a groove cut on the periphery of an end mill with the diameter same as the roller. By using the conventional method, full-sized cutting tools, will restrict the flexibility of choosing cutting tools for wide roller guide. The manufacture of cylindrical cams is complicate and precise work that depends on the generating method and types of machine tools employed. Since the guiding curve cannot be offset exactly along the cylindrical surface, this leads to some approximating problems. Though the tool-paths generation by using the same size tools as rollers is applied in practice, the study of NC program by unequal tools is not available to meet high precision requirement. This proposed 3D offset-based generating method can regenerate tool-paths for standard cutting tools instead of larger ones and implemented on computerized CAM system. Examples with wider grooves are demonstrated to prove its effectiveness.
Experimental Study and Theory Prediction on Adiabatic Shear Critical Conditions of Hardened AISI 1045 Steel
Authors: Li Guo He , Qi Tie Li , Cai Yu Jun , Wang Hong Jun
Published: February 2011

Orthogonal cutting experiments of hardened AISI1045 steel(45HRC) are performed to investigate the influence of cutting conditions on adiabatic shear which occurs in the process of chip formation of many materials. It is found that the cutting speed, cutting depth and rake angle all have influence on adiabatic shear and there is a critical cutting speed at which the adiabatic shear appears. By metallurgical observation, the critical cutting speed under different cutting depths and rake angles are given. A model based on linear pertubation analysis is used to predict the adiabatic shear critical cutting conditions of hardened AISI 1045 steel. The comparison of prediction results and that of expriments shows that this prediction model is valid.
Cutting Test and Analysis of the Emulsified Deep-Hole Cutting Fluid
Authors: Peng Hai , He Dan
Published: February 2011

This paper depicts the types and functions of cutting fluid, compared functions, advantages and disadvantages with several other cutting fluids. According to the characteristics of BTA deep-hole machining and cutting fluid requirements, some of cutting fluids were chose to do the drilling test. In order to satisfy the lubrication and cooling effect of the cutter, the oil-in-water type cutting fluid which through a comparative analysis of the experiment was used in the deep-hole machining, in the meanwhile, it can reduce the economic costs and environmental pollution.
Comparative Study on Force in Milling T10 Hardened Steel with Different Machining Parameters
Authors: Liu Can , Li Guang Hui , Wu Jing Quan , Tan Guang Yu
Published: February 2011

To compare the effects of different machining parameters on force in milling T10 hardened steel, the features of theoretical forces in up and down milling were analysised, and comparative experiments of milling force were made, whose results showed that the maximum component force in down and up milling was in the direction of radial cutting depth and feed respectively, moreover the maximum force in down milling was significantly greater than in up milling. Further orthogonal experiments of up milling and variance analysis were done, and it was found that the effects of rake angle, velocity, feed, axial cutting depth on milling force were significant at levels of α=0.05~0.0025. This study indicates that selecting milling parameters of up milling, high speed, low feed and axial cutting depth be better. This conclusion can be used as reference in designing milling scheme.
The Experiment Research of High-Pressured Cauldron’s Anti-Hydration
Authors: Zhang Wang Nian , Deng Ning , Liu Chang Hua , Sun Guo Dong , Du Xue Fei
Published: February 2011

The method of anti-hydrated of CaO-MgO was investigated in this paper. Take the magnesium calcium granulated substance as raw material, through studied material granularity, weight and other factors to influence anti-hydration of magnesium calcium. It is discovered that granularity of material influence on the anti-hydration of CaO-MgO, and confirm that this method is reliability and validity.
Error Analysis and Simulation of Gear Form Grinding
Authors: Ren Xiao Zhong , Du Xiao Yang , Su Jian Xin , Ding Jun Peng
Published: February 2011

Gear form grinding is an efficient finish machining method for the gears with hard face. There are many factors which have an influence on tooth error in grinding process. In addition to the form error of form grinding wheel, the radial feed depth of grinding wheel has large impact on the tooth error. Based on the principle of gear form grinding, the influence of wheel feed depth on tooth error is analyzed theoretically. The magnitude of error is also analyzed quantitatively according to the simulation result obtained by means of tooth error analysis module, which is developed based on VC + +6.0 software analysis. The research result has a certain reference value for preparing CNC form grinding process and setting machine tool properly.
Performance and Property of Ni Base Coatings by Using Plasma Arc Technology for 18Cr2Ni4WA Steel Repairing
Authors: Xia Cheng Bao , Tu Ming Wu , Pan Qing Jun
Published: February 2011

To understand the structure and performance of Ni base coatings on 18Cr2Ni4WA steel, the key techniques of plasma arc cladding method are introduced. Microstructure and microhardness of the coating clad were analyzed by using Vickers hardness tester,scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).Results show that the phase of the coating is composed of γ-Ni solid solution， nickel boride Ni3B，carbide Cr27C6 and Cr2B3 type chromium boride. The coating has no cracks and does not exhibit porosity, the bonding between layers is compact and the boundaries are not observed. The coating is featured by a homogenized microstructure; small grain and no evident heat-affected zone.
A Modified Isoscallop Height Toolpath Planning Method for Generating Smooth Paths Based on Curve Fitting Method
Authors: Pan Xin , Cai Yu Jun , Qi Tie Li , Li Zhen
Published: February 2011

Isoscallop height toolpath planning method is a high-efficient way to generate toolpaths. However, for some sculptured surfaces, the toolpaths generated via this method may be not smooth, e.g. the cutting direction may alter sharply which badly affecting the machining surface quality. If the curvature of toolpaths can be restricted, paths will be smooth and surface quality can be guaranteed. On the other hand, the machining efficiency may decrease comparing with toolpaths generated via Isoscallop height method. To balance efficiency and surface quality, a modified isoscallop height toolpath planning method based on curve fitting is proposed in this paper. Toolpaths generated via the new method can keep smooth and the efficiency is as high as possible under the restriction of the curvature set by users.
Machining Characteristics of EDM Using Gas Media
Authors: Lin Yao Jang , Lin Yan Cherng , Wang A Cheng , Chen Yuan Feng , Chow Han Ming
Published: February 2011

The aim of this study is to construct a diverse process of electrical discharge machining (EDM) in gas media, and then the new developed machining approach was used to investigate the effects of machining parameters on machining characteristics. Firstly, the feasibility of the EDM in gas media was established with consecutive electrical sparks generated within the machining gap. Moreover, the main machining parameters such as peak current, pulse duration, machining polarity, and gas media supply conditions like air compressed pressure were varied to evaluate the effects on machining characteristics of SKD 61 mold steel in the developed EDM process. The surface morphology of machined surface was observed by a scanning electronic microscope (SEM) to determine the influences of EDM discharge energy on surface integrities. From the result shown in experiments, the material removal rate (MRR) increased with peak current, pulse duration, and air pressure. In addition, the electrode wear rate (EWR) went up with peak current at first, and then attained a peak value with extending the pulse duration and the air pressure, but the EWR declined with further increasing of the pulse duration and the air pressure. Furthermore, the integrities of the machined surface revealed dramatically rough features when the peak current was set at high value. While the pulse duration was further extending, the surface integrities of the machined surface exhibited a smoothened trend obtained by EDM in gas media. Consequently, the developed technique of EDM in gas media possesses the potential of promoting machining performance, reducing environment impact, and extending the EDM applications.
A New Effective Hybrid Optimization Strategy for Rectangular Packing Problem
Authors: Zhou Yu Yu , Rao Yun Qing , Zhang Chao Yong , Zhang Guo Jun
Published: February 2011

In this paper we address a rectangular packing problem (RPP), which is one of the most difficult NP-complete problems. First, greedy biggest space sequencing (GBSS) is presented as a new placement strategy, which is very essential to RPP. Then, borrowing from the respective advantages of the two algorithms, genetic algorithm (GA) and simulated annealing (SA), a hybrid optimization policy is developed. The hybrid GASA is subjected to a test using a set of benchmarks. Compared to other approaches from the literature the hybrid optimization strategy performs better.
Cutting Temperature and Tool Wear in Internal Spray-Cooling Vibration Drilling of Superalloys
Authors: Kong Fan Xia , Zhang De Yuan
Published: February 2011

Vibration drilling with internal spray-cooling method was proposed for the poor thermal conductivity characteristics of superalloys. Cutting temperature and tool wear in vibration drilling, conventional drilling and step drilling were compared by experimental study. The results show that: the cutting temperature in vibration drilling does not change significantly with the hole depth and slowly increased with the increase in the number of drilling; the tool wear rate is reduce, tool life is extened and the processing efficiency is improved.
The Analysis of High-Speed Shearing Mechanic and Cross-Section about Sheet Metal
Authors: Li Yu Gui , Fan Fei , Gui Hai Lian , Ye Quan
Published: February 2011

In the shearing process, these were many problems in shearing, the regularity of metal deformation of shearing was analyzed combined with theory of ductile damage and fracture mechanism of high-speed, the rules of factors which could be affected the shearing was analyzed on the velocity and shearing stress state. These theories would improve the shearing section.
Electrochemical Micro-Drilling with Ultra-Short Pulses
Authors: Hourng Lih Wu , Fan Zhi Wen
Published: February 2011

Electrochemical micro-machining (EMM) has a high removal rate, leaves no residual stress on the surfaces of machined products, and generates a low level of roughness on the surface of machined products. In this work, a novel pulsed power generator is used to support tens of nanosecond duration to drilling. The influences of working parameters, such as pulsed duration, applied voltage, electrolyte concentration, pulse frequency, tool feed rates, and hole depth, on the hole over-cut and conicity in electrochemical micro-drilling are investigated. A high-quality micro hole with a 13.75 μm overcut is drilled into a nickel plate 300 μm thick.