bluuebunny/crossref_metadata_2025 huggingface dataset:
Vibration Analysis Based on AR Trispectrum in Milling Process
Authors: Jiang Yu Yan , Huang Yi Jian , Ye Xiu Cheng
Published: March 2010

This paper presents the use of vibration analysis based on autoregressive (AR) trispectrum in milling process to indicate the relationship between machined surface quality of workpiece and spectrum character under a variety of different cutting parameter settings, such as the depth of cut, the feed rate and the spindle speed. The metal cutting experiments were performed on steel A3 material without using any cutting fluid. The experimental results for slices analysis of trispectra indicated that the spectral peaks were abundant as the milling process went smoothly. The roughness value measured reflects the machined surface quality of workpice. According to the changes for spectral peak and roughness value, a conclusion was made that the proposed trispectrum slices method for choosing cutting parameters and monitoring the machined surface quality in milling process was practicable.
Photocatalytic Analysis and Characterization of Zn2SnO4 Nanoparticles Synthesized via Hydrothermal Method with Na2CO3 Mineralizer
Authors: Wu Yu Shiang , Chang Wen Ku , Jou Min
Published: March 2010

Zinc stannate Zn2SnO4 (ZTO) nanoparticles were synthesized via a hydrothermal process utilizing sodium carbonate (Na2CO3) as a weak basic mineralizer. The samples were hydrothermally treated at 150, 200, and 250oC for 48 h. The X-ray diffraction (XRD) patterns show that the highly-crystalline ZTO nanostructure could be formed in a well-dispersed manner for the 250°C sample at a particle size of less than 50 nm. As determined from transmission electron microscopy (TEM) results, ZTO nanoparticles are face-centered cubic single crystals agglomerated together. The Raman spectra results showed that the ZTO nanocrystals have a spinel structure. Furthermore, photocatalytic activity was tested with methylene blue (MB) by UV irradiation. The ZTO synthesized by the 2 M Na2CO3 mineralizer at 250oC demonstrated excellent photocatalytic activity. The ZTO treated three different ways had three distinct UV-Visible absorption curves, which directly influences their corresponding photocatalytic activity.
Study of Grinding Method of Twist Drills
Authors: Hou Hong Ling , Zhao Yong Qiang , Peng Yu Hai
Published: March 2010

Twist drill is one of the typical cutting tools, usually used inner conical grinding method to trim and dress .it is presented a method of sharpening twist drills in exterior cone surface grinding wheel. A novel sharpening device of linkage-gear compound mechanism is designed. This device can overcome some limitations that can not grind small-diameter drills in the interior cone surface, hence improves the grinding range and grinding quality.
The Influence of Spray Characteristics on Surface Roughness in Minimum Quantity Lubrication Turning
Authors: Zhang Chun Yan , Wang Gui Cheng , Pei Hong Jie , Shen Chun Gen
Published: March 2010

In Minimum Quantity Lubrication machining, cutting fluid is provided as mist. Mist with different velocity and diameter may lead to different cooling, lubrication effect and cutting quality. Thus, cutting quality is highly influenced by spray characteristics in MQL machining. In this study, the mathematics model of mist flow was set up first. Then spray characteristics were tested by a 3-Dimensional Particle Dynamic Analyzer. In order to study the influence of spray characteristics on cutting quality, precision turning of 45 steel was performed by a CNC Super Precision Machine Tool. The results indicate that the lowest surface roughness was obtained by supplying more cutting fluid at proper position for spraying distance of 20mm.
A Study on Cutting Force in Micro End Milling with Ultrasonic Vibration
Authors: Shen Xue Hui , Zhang Jian Hua , Yin Tian Jin , Dong Chun Jie
Published: March 2010

The applications of micro end milling have been gradually broadened to meet the ever-increasing demands for micro parts. In micro milling, premature tool failure and short service life are major problems. In this study, micro end milling with ultrasonic vibration in normal direction is investigated. Kinematical analysis is done to describe the exact trajectory of the tool tip when vibration is applied. Based on which, an analytical model of chip formation is proposed. By accurate calculation of instantaneous chip thickness, the cutting forces in micro end milling with and without ultrasonic vibration are predicted and verified by a slot-milling experiment. As a result, it is found that ultrasonic vibration in normal direction is helpful when reducing the cutting force owing to intermittent cutting effect.
Experimental Study on Milling Force of High-Temperature Alloy GH536
Authors: Xu Hong Hai , Xu Qian , Liu Dong
Published: March 2010

High-temperature alloy GH536 is a difficult-to-cut material. The paper finished milling experiment of GH536 with cemented carbide tool based on orthogonal test, obtained regulations between milling force and feed speed, cutting depth and spindle speed. Results indicate that the milling force increases with feed speed and cutting depth, decreases with spindle speed. Exponential formulas of milling force were obtained by SPSS, variance analysis showed it agreed well with experimental data.
Friction Torque of Rotating Hydraulic Cylinder with Deep Circular Groove Oil Film Face Seal
Authors: Hu Zhi Dong , Jiang Ji Hai
Published: March 2010

Power chuck is an important component for machine tool. In order to solve the existing problem of oil-allocating for rotating hydraulic cylinder of power chuck, a new kind of rotating hydraulic cylinder based on hydraulic slipring is suggested. The deep circular groove oil film face seal technology is applied in the hydraulic slipring for oil transmission. Taking account of the vary of viscosity, the frictional torque of the seal face is simulated in detail. The experiment data prove the preciseness of the theoretical analysis. These theories provide reference for the practical application of the rotating hydraulic cylinder.
Research on Precision Grinding System and Key Technology Based on PMAC-PC
Authors: Zhang Ke , Wu Yu Hou
Published: March 2010

A high speed experimental numerical control grinding system based on PMAC-PC was designed, realized machining and measurement integration. High speed motorized spindle finite elements dynamics and thermal characteristics, force analysis of linear motor feed element and parameters setting method based on PMAC, work piece roundness error measurement technology were researched. The grinding experiment and dynamic measurement indicated that the system possessed good following performance and stability; grind the elliptic work piece in the system.
Research on Chatter Suppression in Machining Thin-Walled Components Based on Rigidity Optimization
Authors: Ren Jun Xue , Yang Bi Qi , Liang Yong Shou , Tian Wei Jun , Yao Chang Feng
Published: March 2010

Precision machining of thin-walled complex components has been a serious challenge, and the machining errors are mainly due to cutting force which can induce tool-workpiece deformation and chatter vibration phenomenon. Based on the principle of stiffness optimization and material removal sequence optimization, rigidity of thin-walled component is greatly improved with non-uniform allowance distribution and spiral milling process techniques.
Study on the Cutting Mechanism of Remanufacture Deposited Materials in the Impactive Condition
Authors: Wu Zhi Yuan , Wang S.H. , Tian Xin Li , Zhang Shu
Published: March 2010

Three cutting tools, YG8, YT15 and YW1, which are different in hardness and toughness, were adopted for deposited materials cutting. From the analysis of test results, it can be known that the toughness is the most importance factor for improving cutting capability when the hardness of deposited materials is low. And with the growth of hardness of workpieces, the hardness of cutting tools plays more and more important roles. When the hardness of deposited materials arrives to HRC56, the hardness of cutting tools becomes the main role for improving cutting capability. On the basis of the results of two orthogonal experiments and extremum deviation analysis, the best scheme for three deposited materials were achieved after obtaining the best level of the factor by computation.
Nonequivalent Milling of Roller Gear Cams Based on Approximation Method of Offset Surface
Authors: Ge Rong Yu , Feng Xian Ying , Guo Pei Quan
Published: March 2010

The roller gear cam surface is manufactured with nonequivalent milling method in many cases, by which the machining error is unavoidable. In order to simplify the tool position, we can transform one problem approximating the designed surface with the tool envelope surface to another problem approaching the theoretical tool axis trajectory surface with the actual one. Furthermore, the theoretical tool axis trajectory surface, which is an offset surface of the designed cam surface, is reconstructed by the NURBS ruled surface. In order to find the best tool axis vector to minimize the machining error, a simple least square approximation method is established to figure out all the control points of the NURBS tool axis trajectory surface. A numerical calculation and simulation example is described to verify the effectiveness of the tool position method proposed in the paper.
Advanced High Strength Steel Sheet Forming and Springback Simulation
Authors: Chen Ke , Lin Jian Ping , Lv Mao Kang , Wang Li Ying
Published: March 2010

With the increasing use of finite element analysis method in sheet forming simulations, springback predictions of advanced high strength steel (AHSS) sheet are still far from satisfactory precision. The main purpose of this paper was to provide a method for accurate springback prediction of AHSS sheet. Material model with Hill’48 anisotropic yield criterion and nonlinear isotropic/kinematic hardening rule were applied to take account the anisotropic yield behavior and the Bauschinger effect during forming processes. U-channel forming and springback simulation was performed using ABAQUS software. High strength DP600 sheet was investigated in this work. The simulation results obtained with the proposed material model agree well with the experimental results, which show a remarkable improvement of springback prediction compared with the commonly used isotropic hardening model.
Study on Precision Grinding of Involute Cams on a Double-Disc Device
Authors: Ma Yong , Liu Heng , Li Ke Hong , Wang Li Ding
Published: March 2010

The involute cam is used for generating tooth form of an involute gear in gear grinder with involute cam-link stopper, and its profile error is one of the factors which decide the tooth form precision of gear. The conventional processing means of involute cams can't achieve a sufficient accuracy. In this paper, a double-disc mode grinding device is introduced. Based on analysis of grinding principle, the device's structure and working process are described, and the main sources of grinding profile errors are analyzed. It is confirmed that the introduced device has the ability of accomplishing a highly precise grinding of involute cams.
Trajectory Interpolation in CNC Grinding of Indexable Inserts
Authors: Tian Xin Cheng , Deng Xiao Hong
Published: March 2010

Most of the commenly adotped interpolation algorithems are for the curve machining on CNC machine tools with Cartesian coordinates configuration. For a CNC machine tool with non-Cartesian configuration, new trajectory interpolation algorithem must be developed to machine complex part sueface. Based on the analysis of the geometric characteristics and the CNC grinding principle of indexable inserts, this paper proposes two interpolation algorithems to grind the nose surface of indexable inserts with constant or variable back angle. The algorithm precision analysis is also made in this paper.
CFD Research on Aerostatic Bearing with Tangential Supply Holes
Authors: Yu He Chun , Ma Wen Qi , Wang Zu Wen , Xu Li Fang
Published: March 2010

The radial aerostatic bearings with reversely tangential gas supply holes have been proved successfully in some applications to improve the dynamic stability. However, the concept lacks firm theoretical support. Aerostatic bearings with reversely tangential gas supply holes and radial gas supply holes were designed. The finite volume method (FVM) was used to solve the three-dimension flow field, the static characteristics of them were studied, and the following conclusions were drawn: The tangential gas supply holes can improve the pressure distributions in the working clearance, but they can’t effectively improve the load capacity and stiffness. The improvement of the characteristics of aerostatic bearings with tangential gas supply holes is at the expense of excessive gas consumption. For aerostatic bearings, when the eccentricity ( ) is large and the rotor speed ( ) is high, the dynamic effect can effectively improve the load capacity and stiffness.
Improving Plastic Thermoform Quality with Uniform Heating Technology
Authors: Zhang Zhi Guo , Lin Chen , Feng Da Kui , Still Ray
Published: March 2010

The experimental studies were conducted to study the plastic thermoforming heating process. The heaters performance has been evaluated from two different ways: heating water calorimeter for heating efficiency and heating plastics for thermoform processes. The studies of the heaters include gas-fired heater and electric heater. Transient heating processes of plastics were also studied to investigate the heater’s performance on plastics. The surface temperature of plastic at the end of heating process was measured by IR camera. The heating cycle time, surface temperature uniformity of plastic and energy consumed for the heating cycle by different heaters were discussed. The pros and cons of different heaters for plastic heating process were also discussed in this paper.
Cutting Forces and Tool Wear Patterns in Five-Axis Milling Fe-Based Super Alloy with Bull-Nose End Mill
Authors: Wan Yi , Liu Zhan Qiang , Ai Xing
Published: March 2010

Five-axis milling is widely used in machining of complex surfaces parts. Part quality and productivity are extremely affected by cutting force and tool wear, especially thin-walled complex surface, such as turbine blade. Although extensive research has been conducted on cutting force and tool wear in 3-milling process, very few are on 5-axis milling and bull-nose mills. This paper presents cutting forces with various cutting conditions as well as tool wear patterns in five-axis milling super alloy, which is essential to cutting vibration and defelction analysis of thin-walled complex surfaces parts. The roles of lead angle and tilt angle in five axis milling were investigated, which provide data for NC program edit. In addition, experiments in this research proved that tool wear played affected cutting forces outstandingly.Therefore, tool wear played an very important role in tool change.
Research on Design and Application of Control System in Machine Tool Modification
Authors: Shen Xiao Long , Zhang Lai Xi , Ren Cheng Gao , Zhou Zhi Xiong
Published: March 2010

Technical reform of the used equipment in engineering, not only economizes the purchasing funds of the equipment, but also exploits the potential of the current equipment, at the same time, improves the level of automation of facilities and production quality. In this paper, the mathematics model and the system responding analysis on the mechanism are provided based on the dynamic analysis of mechanism. The design scheme of drilling machine workbench system has been optimized by improving the design and adopting appropriate compensations to system errors.
Tool Wear Investigation on Dry Electrostatic Cooling in Turning Titanium Alloy Ti6Al4V
Authors: Wang Hui , Han Rong Di , Wang Yang
Published: March 2010

The machinability of Titanium Alloy Ti6Al4V is poor, the traditional methods to machining is application of cutting fluids with the active additives which cause environmental pollution and health problems. In this paper, the dry electrostatic cooling was applied instead of cutting fluid for the aim of green cutting Ti6Al4V. The ionized device and gas supply system was set up, the effects of dry electrostatic cooling, emulsion oil and dry cutting on tool wear have been examined in turning of Ti6Al4V with carbide tools YG8, the curve between tool flank wear and cutting time was proposed, and the equation between cutting speed and tool life was set up. The results of experiments indicated that application of dry electrostatic cooling reduced the tool wear and increased the tool life. The research results show that clean production was achieved in metal cutting associated with dry electrostatic cooling.
Experimental Research on Turning Vibration Deduction with Intelligent Material Based on LabVIEW
Authors: Zhang Yong Liang , Zhou Yuan , Liu Jun
Published: March 2010

The structure and working process of turning vibration deduction system with intelligent materials based on LabVIEW programming was introduced. Meanwhile, the cylindrical turning vibration deduction experiments were carried out on CA6140 common lathe with this system. The experimental results showed that cutting vibration can be effectively inhibited by adopting intelligent materials. However, the optimum anti-vibration voltages are different under different cutting parameters. Therefore, relations between the cutting condition and the optimum anti-vibration voltage will be the focus in the next stage.
Non-Special Dressing Electrode Experimental Study on ELID Grinding
Authors: Zhang Fei Hu , Tong Fu Qiang , Zhang Yong , Luan Dian Rong
Published: March 2010

The traditional ELID Grinding Technology has many limitations in grinding small diameter hole and spherical face. As a solution, a new method for ELID grinding - the fourth generation ELID Grinding Technology, ELID IV, is presented in the recent research. To serve the industrialized application of ELID IV, a series of experiments were performed to reveal principle of ELID IV. Results of these experiments indicated that: (1) electrolyse function is enhanced obviously when the workpiece is connected to the positive pole of the power supply using 45 steel as the material of test piece; (2) the relationship between the effect of electrolysis and the electrode gap is studied by using the 120 # Rail Based grinding wheel on the cemented specimens carbide for electrolytic grinding, and 1mm is determined the best electrode gap.
Study on the Modeling Method for Finite Element Analysis of Chip Formation Process
Authors: Xie Li Jing , Li Lin , Ding Yue , Wang Xi Bin
Published: March 2010

FEM is a powerful tool for predicting cutting process variables, which are difficult to obtain with experimental methods. In this paper modeling techniques on chip formation by using the commercial FEM code ABAQUS are discussed. Because of the limitations of Lagrangian and Eulerian methods, a modeling method based on ALE (Arbitrary Lagrangian Eulerian) technology is proposed to simulate the chip formation process. It consists of three chip formation analysis steps, i.e. initial chip formation, chip growth and steady-state chip formation. With this modeling method, high speed turning process of stainless steel 2Cr13 is simulated. And the predicted variables are compared with experimental data. It has been found that the results are in good agreement with the experimental ones.
Research on Safety Decline of High Speed Milling Cutter
Authors: Jiang Bin , Zhang Wei , Zheng Min Li , Yang Yin Jin
Published: March 2010

This work explored the process of safety decline based on stress field and deformation analysis of cutter, founded vibration models of centrifugal force and cutting force, and investigated the effect of dynamic balance precision and natural frequency on safety and stability of cutter. Using the model of maximal residue height on machining surface based on the vibration of cutter and experiment results, characterized safety decline behavior of high speed milling cutter. Experiment results verified that safety decline caused by the vibration of centrifugal force was much higher than the vibration of cutting force. The results indicate that the deformation of cutter and relative displacement of subassembly change mass distribution of cutter with rotational speed increasing in unimpaired state of cutter’s integrity, direct results are dynamic balance precision decline, the safety and stability state of cutter gradual deterioration because of the vibration, the safety of cutter occurs a dynamic decline in high speed milling.
The Design Method of Punches and Dies for Progressive Die of Motor Core Based on Association Design Technology
Authors: Jia Z.X. , Li Hong Lin , Wu Hong Bing , Li Jian Jun
Published: March 2010

This paper describes a structural design tool for punches and dies in 3D progressive dies of motor core based on association design technology. Based on the classification and 3D modeling method of punches and dies, the associated model is set up to describe the holes on plates of die set for punches and dies. The proposed tool integrates the design knowledge of progressive dies for motor core to automate the design for punches, dies and corresponding holes on plates. This design tool is constructed on a PC and integrated with SolidWorks software. We use progressive die for the motor core with rotator, stator and vice-stator as a concrete example to demonstrate the power of the design tool. The results show that it can not only improve design quality but also save both time and costs dramatically.
Preparation of Novel Silica Nanoparticle/Polystyrene Composite Microspheres in a Pickering Emulsion
Authors: He Yong Jun
Published: March 2010

Silica nanoparticle/polyaniline composite microspheres (SPCMs) were synthesized in a Pickering emulsion for the first time. The products were characterized by SEM and FTIR. The SPCMs were consisted of a polystryrene core and a silica nanoparticle shell. The average diameter of the SPCMs was about 3.3 μm. A mechanism for the formation of the SPCMs was discussed. The route reported here may be used for the preparation of other novel composite nanostructures.
Self-Assembly of Cuprous Oxide Micro/Nanostructures by Photo-Reduction Method
Authors: Chang Wen Ku , Wu Yu Shiang , Shen Zhong Han
Published: March 2010

This study used a photo-reduction method to investigate cuprous oxide (Cu2O) self-assembled micro/nanostructures, and design a test specimen with an electron concentration gradient distribution. It also observed the Cu2O reduction of the self-assembled structure with respect to electron density. SEM analysis was adopted to analyze the growth mechanism and growth model. The results showed that, its structure size increased with photo-reduction time, and as the reduction solution concentration increased, its structure crystallinity declined. The basic unit of a self-assembled microstructure was Cu2O at a diameter of 10~15nm, then these particles conglomerate in self-assembly to form various kinds of Cu2O micro/nanostructures with respect to reduction electron density, and primarily presented in the form of a cone or cube. In the process of continuous self-assembly, there were many micro-defects under the perfect crystal surface. Considering the growth rate, the final growth surface of the structure was (111) or (100).
A Dimensional Analysis Model for Geometric Size Effects of Single Crystals
Authors: Chen Xiao Liang , Lin Shun Hong , Tian Zuan
Published: March 2010

Due to the relatively high surface-to-volume ratio, the surface effect can be significant for micro/nano-scale materials. This paper focuses on geometric size-dependent strength mechanisms of micro/nano-scale metal single crystals. A dimensional analysis model relating surface energy with the geometric size-dependent yield strength is presented and compared with results of microscale uniaxial compression tests on Ni and Au single crystals. The results indicate this model can predict the geometric size effects on the yield strength of micro/nano-scale metal single crystals.
Structure and Magnetic Properties of Carbon Encapsulated Co Nanoparticles Prepared by the Pyrolysis of Mixture of Sucrose and Cobalt Nitrate
Authors: Xue Jun , Chen S.C. , Tang H.K. , Xiang H.K. , Wang X.H. , Cao H.
Published: March 2010

Carbon-encapsulated Cobalt nanoparticles were synthesized with sucrose as carbon source and cobalt nitrate as metal source in nitrogen atmosphere. The weight of purified sample could arrive around 12-20 grams at one time. The as-prepared CECNPs sample was characterized by transmission electron microscopy (TEM), X-ray diffraction technique (XRD), vibrating sample magnetometer (VSM) and Raman spectroscopy. The results showed CECNPs was typical core / shell structure on nanometer scale, the core was cobalt single crystal, the shell was graphitic carbon, and the particle size was about 30nm. The magnetic measurement revealed that CECNPs was ferromagnetic material with the quite small remanent magnetizations Mr of 3.7emu/g and coercive forces Hc of 275Oe at room temperature.
Effect of Combined Shot Peening Process for Surface Nanocrystallization Method on Fatigue Strength of TC4
Authors: Wen Ai Ling , Wang Sheng Wu , Ren Rui Ming , Yan Xiu Xia
Published: March 2010

In order to enhance the fatigue limit of titanium (TC4), the combined shot peening were employed. Firstly, nano-crystallization in surface layer of TC4 were carried out by high-energy shot peening, and then the surface repair shot peening with small balls were introduced for repairing the surface damage by high-energy shot peening, and reducing the surface roughness, thus to enhance the quality of nanocrystalline surface layer of TC4. The fatigue tests were performed using the specimens treated by the combined shot peening. In addition, the influence factors of fatigue limit, the behavior of fatigue crack initiation and propagation etc. are discussed. The results showed that the fatigue limit of TC4 specimen treated by high-energy shot peening is increased by 13%, while the fatigue limit of TC4 specimen treated by the compound shot peening process is increased by 34% (165MPa). The main reason of fatigue improvement is considered to be that the combined shot peening process may effectively repair the surface damage, and also there is the certain relationship between the fatigue limit improvement and the surface roughness reducing.
Fabrication of PLLA Scaffolds by Low-Temperature Deposition from a Ternary Polymer-Solvent System
Authors: Zheng Xiong Fei , Zhai Wen Jie , Sun Tao , Liang Ying Chun
Published: March 2010

A completely interconnected macroporous and microporous poly(l-lactic acid) (PLLA) scaffold was fabricated from a PLLA–dioxane–water ternary system by an advanced manufacturing technology called low-temperature deposition manufacturing. A proper fraction of water and PEG added into the polymer solution induces liquid-liquid phase separation and gelation. The liquid-liquid phase separation brings in a new micro morphology and gelation effect produces higher fabrication accuracy.
Preparation of CaCO3-Containing Geopolymers for Green Concrete
Authors: Han Hyun Geun , Ko Young Hwa , Seo Dong Seok , Kim Gab Joong , Lee Jong Kook
Published: March 2010

Geopolymers were prepared by using the dried fly ash from industrial by-product, NaOH as alkaline activator and Na2SiO3 as liquid glass. Calcium carbonate from a clam shell was added to provide attachment and growth of environmental organisms on the geopolymers. We investigated the effects of a shell powder contents on the microstructure and bonding properties of the geopolymers to normal cement. The major chemical compositions of fly ash were Si and Al at the ratio of 2 to 1 in wt%. The shell powder with layer sheet consisted of aragonite phase. As increasing the amount of the shell powder, fly ash was not polymerized and remained spherical. The bonding between geopolymers and normal cement was obtained when 0-15 wt% of the shell powder was added. On the other hand, bonding was not achieved with higher shell contents of 20-25 wt%.
Experimental and Theoretic Research on Solar Power Membrane Distillation
Authors: Cui Hong Jiang , Sun Pei Ting , Li Ming Hai
Published: March 2010

Air gap membrane distillation experiments of different temperature and mass flow rate of working fluid were done for the use of solar power and setting up the mathematical model of AGMD’ heat and mass transfer. The calculation correctness of mathematical model was discussed and the thermal efficiency of membrane distillation system was calculated. The results showed that the experimental flux of membrane distillation reached 49kg/m2•h and the biggest relative error is less than 9% between results of experiment and mathematical model calculation. The mathematical model can be used to forecast the process parameters of membrane distillation. The highest thermal efficiency of this system is 68% and the main influencing factors of thermal efficiency are temperature and mass flow rate of working fluid.
Study on the Differential Thickness Ratio Effect on Formability of TWB Based on Numeric Simulation
Authors: Xue Song , Zhou Jie
Published: March 2010

The differential thickness ratio of blanks plays an important role on the formability of TWB. The formability of TWB square cup is analyzed by numeric simulation in differential thickness ratio. The laws influencing the formability of TWB square cup are summarized, that the formability of TWB goes worse when the differential thickness ratio increased and it was applied in the production of the center pillar of car door.
An Automatic Shake Mechanism for the Biomass Pyrolysis Feeding
Authors: Zhang Jun , He Xin Yan , Wei Xin Li
Published: March 2010

Successful feeding is critical to biomass utilization processes such as pyrolysis. The biomass particles in hopper frequently become bridge or adhere to the wall, and it does not provide the required uniform and continuous flow of the feedstock materials. Therefore, an automatic shake mechanism is devised which is set in the hopper and driven by the rotating of the first screw. The experiments were done using the automatic shake mechanism. The results show that the biomass particles can deliver uniformly by screws without extra power consumption and increased the delivery capacity.
Study on the Performance and Biodegradability of Three Kinds of Biodegradable Dishware
Authors: Guo An Fu , Li Jian Feng , Li Fang Yi , Wei Bao Kun , Li Jian Yong
Published: March 2010

The performance and biodegradability of plant fibre and starch dishware (PFSD), pulp model dishware (PMD) and starch plastic dishware (SPD) were studied. The experimental results showed that these three kinds of dishware satisfy the requirements of use. The fungi growth degree and the weight loss percentage of these materials were analyzed. The experimental results showed that the growth grade of PFSD and PMD were both Ⅴgrade and the weight loss rate respectively were 41.59% and 82.73%, the biodegradability of SPD was not obviously observed in the whole process of the experiment. The degradation speed was analyzed, which showed that the degradation speed of PFSD and PMD was faster in the former two weeks than that in the latter two weeks. The biodegradability of each kind of dishware were compared under three different environments, the results showed that inoculation environment (T=30°C, RH>90%, 28 days) is the best environment for dishware to biodegrade by fungi.
A Method of Multi-Environmental Spatial Scales Division in LCA Based on Chinese Region-Specific
Authors: Wang Xiao Wei , Li Fang Yi , Li Jian Feng , Wang Li Ming , Chen Xiao Xu
Published: March 2010

Traditionally LCA generally focus on a global scale and on steady-state, linear modeling.
How to reflect the varying and complicated spatial characteristics of environmental impacts of large numbers of processes is in urgent need for improving the practicality of the LCA, especially for that with distinct environmental diversity in China. Based on the Chinese environmental policies and standards, a method of multi-environmental spatial scales division in LCA is proposed. First, environmental space types are discussed according to the relations between the life cycle inventories, impact categories of LCA and the environmental spatial characteristics. Second, the environmental spatial scale coefficient is proposed and defined in order to quantify the spatial characteristics and used in the calculation for the environmental impact potentials of products. The method of calculation for the coefficient is presented by analyzing the endure capacity of regional environment. Finally, this method is applied to study the spatial characteristics of ambient air quality and other environmental space types.
Fluid Clamping Devices Based on Area Effect Stroke Amplifier Driven by Shape Memory Alloys Wires
Authors: Li Xin , Zhou Lu Fei , Wang Ming Di , Zhong Kang Min
Published: March 2010

Shape Memory Alloys (SMA) is mainly used in Microsystems because of its micro strain. A new kind of clamping device based on area effect stroke amplifier and driven by SMA wires is introduced in this paper. With the micro strain enlarged by stroke amplifier and pressure transmitted via closed pipeline, a greater displacement can be obtained to clamp the workpiece. This clamping device has prominent advantages in great stroke amplifying ratio and green aspect. Moreover, remote clamping and automatic control are easy to implement because of the high flexibility of fluid.
Modification of Pellet Materials by Low Temperature Plasma
Authors: Wang Yong Jun , Wang Zhen Qing , Zhu Li Nan
Published: March 2010

Low temperature plasma made some modifications of pellet materials (activated alumina and haydite) placed between electrodes. It altered the characteristics of pellets after discharge, such as the pellet surface element proportion, binding energy, specific surface area, pore volume and pore size. The activated alumina surface parameters of specific surface area, pore volume and pore size increased after discharge, which was good for catalytic activity. The original pores on haydite surface were destroyed, and bigger holes were formed. Activated alumina would be polarized when placed between discharge electrodes, which enhanced the electric field intensity. Due to the effect of plasma, the solid pellet surface was modified, which was useful for pellet catalysis in application.
Novel Non-equidistant Optimum GM(1,1) Model with Modified nth Component be Taken as Initial Value and its Application to Metal Cutting
Authors: Luo You Xin
Published: March 2010

Based on grey system theory, a novel kind of non-equidistant optimum grey model GM(1,1) with optimizing modified the nth component taken as initial value of response function of grey differential equation and reconstructing the background value function to obtain the approximately expressions of parameters of the background value function was proposed, the method of precision inspection was introduced. The example was given. The method can be used for model establishing on equal interval, as well as on non-interval. Moreover, GM(1,1) model’s fitting precision and prediction is advanced and the scope of application is enlarged. The model is simple and practical, and has a generalizing value in metal cutting data process.
Study on an Inventory Decision Model in an Assembly System
Authors: Cai Jian Hu
Published: March 2010

In this paper, an assembly system with two suppliers and one assembler is introduced, and the supply chain operates under a VMI mode. Traditionally the suppliers decide their inventory quantity before the selling season, which is a classical newsvendor model. This paper assumes that the suppliers also can supplement products if the demand is unmet in the selling season. All members’ optimal decisions are gained. And a numerical example is introduced to illustrate our findings.
Research of Sequencing Working Steps Method for Box Part
Authors: Zhang Sheng Wen , Liu Yang , Fang Xi Feng , Wang Gui Cheng
Published: March 2010

A reasonable process route is important for assuring the product quality and improving the production efficiency. This paper analyzes the sequencing essence of box part working step，and on the basis of deducting the concept of “Inner Product Angle Cosine of n Dimension Vector”, this paper advances a new algorithm called as “Inner Product Angle Cosine of n Dimension Vector” to sequence the working procedure. Through analyzing the algorithm flow and combining with the example used to demonstrate it, this algorithm is proved to own a more reasonable math theory basis, an overall optimization character and a stable convergence character in a more strict sense.
Dynamic Reentrant Scheduling Simulation for Assembly and Test Production Line in Semiconductor Industry
Authors: Liu Ai Jun , Yang Yu , Liang Xue Dong , Zhu Ming Hua , Yao Hao
Published: March 2010

Production scheduling in semiconductor production line is a complex combinatorial optimization problem. It is featured by reentrant production, product variety, frequent machine breakdown and especially reentrant phenomenon and dynamic randomness, which conduces enormous complexity to production line scheduling and management. Based on the resource conflict resolution strategies, dynamic scheduling models for a semiconductor production system are proposed here, aiming at finding maximum machine utilization, optimal man-machine ratio (MMR) and maximum output. Then the validity of the model is illustrated by a simulation case.
An Effective Immune Based Approach for the No-Wait Flow Shop Scheduling Problems with Multiple Machines
Authors: Hsieh Yi Chih , Lee Y.C. , You Peng Sheng , Chen Ta Cheng
Published: March 2010

For scheduling problems, no-wait constraint is an important requirement for many industries. As known, the no-wait scheduling problem is NP-hard and has several practical applications. This paper applies an immune algorithm to solve the multiple-machine no-wait flow shop scheduling problem with minimizing the makespan. Twenty-three benchmark problems on the OR-Library are solved by the immune algorithm. Limited numerical results show that the immune algorithm performs better than the other typical approaches in the literature for most of instances.
Filtered Beam Search Based Flexible Job Shop Scheduling Problem with Transportation Time
Authors: Wang Shi Jin
Published: March 2010

Classical flexible job-shop scheduling problem (FJSP) does not consider the transportation time of jobs movement among different machines, which reduces the potential significance of its practical applications. This paper defines an FJSP problem with transportation time incurred by movement of jobs with one Automated Guided Vehicle (AGV) and one Load/Unload (L/U) station. A filtered beam search (FBS) based meta-heuristic algorithm is presented to solve this problem. The detailed procedure of the algorithm is described, and an example is shown to illustrate the algorithm. Finally, preliminary experimental results with comparisons of other dispatching rules demonstrate the feasibility and effectiveness of the proposed algorithm for the FJSP with transportation time.
An Optimization Approach for Semiconductor Wafer Fabrication Scheduling Problem
Authors: Cao Zheng Cai , Qiao Fei , Wu Qi Di
Published: March 2010

Due to the increasing scale of scheduling problems, the study is to explore an effective optimize scheduling approach for the semiconductor wafer fab. Semiconductor manufacturing is widely regarded as one of the most complex manufacturing processes in the world. The particular complexity, characterized by reentrant flows, uncertainties, mixed processing styles, etc., leads to a great challenge in its scheduling. Without powerful scheduling techniques it becomes practically impossible to design a manufacturing system. So, by means of a new coding method, and the adaptive mechanism of crossover and mutation, an improved immune algorithm (IA) is presented to solve the scheduling problem. The algorithm is based on clonal selection and affinity maturation for finding optimal solutions. To demonstrate the efficiency of the IA, some numerical experiments are carried out. The results show that the IA will yield a more efficient solution than several other scheduler.
Modeling and Simulation of Re-Entrant Semiconductor Wafer Fabrication Lines with PM Using GSPN
Authors: Jiang Zhi Gao , Dong Ming , Tian Peng , Yang Dong
Published: March 2010

Semiconductor wafer fabrication factories are characterized by re-entrant flows, dynamic and uncertain environments, strict production control requirements and so on. Re-entrant flow means a product routing that consists of multiple visits to a workstation during the manufacturing processes. In this paper, a modeling approach based on generalized stochastic Petri nets is presented. Specifically, a Petri net model representing a re-entrant flow line with three centers and six machines is modeled. Work release policies (WRP) and queuing disciplines (QD) are also added to the model, which take into account the machine preventive maintenance (PM) requirement. Finally, a simulation study is used to analyze the model, which provides support for scheduling decision in shorter time.
A New NURBS Tool Path Generation Algorithm for Precise Sculptured Surface Machining
Authors: Yang Xu Jing , Sun Guang Yong , Li Qing
Published: March 2010

This paper proposes a new approach to tool path generation in precision machining of parts with sculptured surface. It aims to develop an effective NURBS fitting algorithm suitable for machining sophisticated parts requiring smooth profile on sculptured surface. In order to generate NURBS tool path with fewer control points, a dual-loop fitting technique is proposed in this paper. A general sculptured surface model is used to test the effectiveness of this method. It is shown that the proposed algorithm proved to be robust and effective in generating precise NURBS tool path. This makes the proposed algorithm suitable to convert conventional CNC tool path to more precise NURBS tool path. This approach may be of potential to be widely implemented in the manufacturing industry.
Neural Network Based Computer-Aided Process Design System for Wire Bonding Quality Improvement
Authors: Gao Jian , Li Chuan Wei , Li Ke Tian , Li Ze Xiang , Chen Xin
Published: March 2010

The relationship between the process parameters and bonding quality is very complicated due to the features of non-linear and coupling relation. It’s therefore hard to express their relationship in an exact mathematic model and very difficult to obtain an reasonable parameters setting to get high bonding quality. In this paper, a wire bonding process model based on BP(Back Propagation) neural network is proposed, and based on this model a computer-aided process design system for bonding quality improvement is developed through VC++6.0. Based on the training data from design of experiments (DoE), the BP network is built. The system is validated by test data and the testing result shows that the predicted error is samll and reasonable and the system developed can be used for parameter optimization and quality improvement.
Research on Stamping Spring-Back Prediction for Car Body Panel Based on BP Neural Network
Authors: Zhou Xin Jian
Published: March 2010

On the basis of orthogonal test analysis of variance, BP neural network is used to forecast quantitatively the stamping spring-back of front panel of a car body, namely the engine hood, under the conditions of different stamping parameters. Firstly, BP neural network prediction model is established and sample training is done in Matlab. Then, the spring-back prediction using BP neural network and the result of spring-back simulation using Dynaform is compared to verify the precision and stability of the prediction model. Lastly, modification is made to the BP neural network according to practical stamping parameters and an efficient BP neural network model is established. Using this model, stamping spring-back prediction for the front panel of a car body is made. The spring-back prediction could then be used for spring-back compensation in the mould design of the front panel.
Study on Micro-Displacement Stage Driven by Piezoelectric Actuator
Authors: Jing Dan , Lin Jie Qiong , Li Ying Chun
Published: March 2010

In order to improve the accuracy of position for the machine, a micro-displacement stage is deigned based on piezoelectric actuator and flexible hinge. The structure of the flexible hinge is analyzed reasonably. With the hybrid method of feedforward and digital PID control, the control process of the micro-displacement stage can be corrected and compensated. It is indicated by experiment that the maximum stroke of the micro-displacement stage is , and the position accuracy is , which can meet the requirement of precision and ultra-precision machining.
Study on the Manufacturing Method of the Biomimetic Drag Reducing Morphology Replication Mold
Authors: Li Xiang , Cai Jun , Zhang De Yuan
Published: March 2010

In order to manufacture the drag reducing morphology replication mold used for biomimetic drag reducing film fabrication, the real shark skin and micro riblets machined with ultrasonic elliptical vibration cutting (UEVC) were used as templates respectively, followed by the casting process. The manufacturing process and the morphology quality of the molds was studied, and the biomimetic drag reducing effect and suitable application field was analyzed. The result indicates that: the bio-replicated forming mold based on shark skin is superior in morphology similarity with the real shark skin; the UEVC mold can achieve simplified riblets with high quality, and is feasible for large area mold manufacture and riblets spacing adjustment. The riblets morphology made with UEVC has wider application field than the shark shin morphology because of its flexibility of spacing adjustment.
Laminated Photoresist Sacrificial Layer Process for 3-D Movable Suspension Microstructures in LIGA-Based Surface Micromachining
Authors: Wu Yi Bo , Ding Gui Fu , Zhang Cong Chun , Wang Hong
Published: March 2010

The fabrication process of three-dimensional (3D) high-aspect-ratio MEMS devices entirely made of electroplated metals with suspending multilayered microstructures is reported. The technology used is a LIGA-liked micromachining process, called the laminated positive photoresist sacrificial layer process (LPSLP). The LPSLP allows in UV-lithography not only for thick resist mould for electroplating of cascaded metal structures but also for the sacrificial layer for supporting mechanically the suspensions. So far the LPSLP procedure has incorporated with more than five sacrificial layers, which allows for the creation of overhanging structures and freely moving parts like out-of-plane cantilever stacks. A description of the underlying fabrication principle and processing details is discussed in this paper. Thus the proposed procedures open a low-cost route for fabricating micro-components such as cantilevers, bridges, movable electrodes, and freestanding parts.
Numerical Simulation and Experimental Investigation of Tool Edge Radius Effect on Micro-Cutter Wear in Micro-End-Milling Process
Authors: Yang Kai , Bai Qing Shun , Liang Ying Chun
Published: March 2010

The micro-end-milling process of aluminum alloy Al2024-T6 has been investigated by numerical simulations and experimental approach. The effects of different tool edge radii on the micro-cutter wear were investigated. A three-dimensional finite element model is adopted to determine the effects of tool edge radii on the effective stress and micro-cutter wear during the micro-end-milling process. It is observed that the the tool nose wears out much more quickly due to the high maximal effective stress occurring in this zone. The experimental verification of the simulation model is carried out on a micro-end-milling process of aluminum alloy 2024-T6. The experimental results of the micro-cutter morphologies are in a good agreement with the simulation results. The experimental results show that the model is suitable for studying the mechanism of micro-cutter wear.