bluuebunny/crossref_metadata_2025 huggingface dataset:
Research on Thermal Error Modeling and Simulation Technique of CNC Based on Stepped Approximation Method
Authors: Tian Liang Ju , Huang Yan Qun , Liu Ming
Published: February 2011

On the basis of thermal error experiment in CNC, the paper reaches a conclusion that at different sampling time, the thermal error model is different from each other. Therefore, this paper proposes a Stepped Approximation Modeling(SAM) Method on thermal error by improving the Multivariable Regression Analysis Modeling Method. The model examples are calculated and compared with presented experiments data. The results show that the SAM has a high accuracy in the thermal error modeling of CNC.
Study on the Effects of the Geometrical Parameter of Twist Drill on the Drilling Performance of Stainless Steel
Authors: Gao Xing Jun , Zou Ping , Liu Qing , Gao Hong He
Published: February 2011

The key geometrical parameters of twist drills that had a great effect on the drilling performance of stainless steel were studied by Pro/E and DEFORM-3D softwares. The influence of chisel edge and tip angle of twist drill on the drilling force, torque and tool wear in the drilling process was researched, and meantime the effects were introduced by shortened the chisel edge length or adopted S-shape helical drill points as well. The tip angle of drill bit that affected the main cutting edge length, the cutting load on unit length, the proportion between cutting width and cutting thickness in the cutting lay, the cutting force, the torque, the chip formation and chip removal was introduced in detail. The choice of tip angle of twist drill was introduced. In drilling, it has important instructional significance for improvement of life of drill bit, advancement of productivity of drilling and processing quality of hole.
Research on Dynamic Fatigue Strength Criterion of BTA Deep Hole Boring Bar for Consideration Vortex Surrounded by Internal and External Cutting Fluid
Authors: Zhao Wu , Chen De Jie
Published: February 2011

Fatigue failure is the most common failure mode of boring bar in the deep-hole boring processing system. For solving the problem of fatigue failure on boring bar, the new fatigue strength criterion of boring bar is proposed considering the working state including internal and external cutting fluid vortex, linear crack of the across-section, and the maximum bending - torsion coupled stress of boring bar. Firstly, approximate calculation formula of the maximum bending stress was derived considering internal and external cutting fluid coupled effect induced vortex motion. Secondly, near the region of crack tip, the maximum shearing stress was studied when the failure modes of boring bar was considered to linear crack on its cross-section. Finally, the new fatigue strength criterion was established based on bending-torsion combination alternating stress fatigue strength theory. An example calculation in practice showed that if fatigue strength of boring bar is satisfied to the new fatigue strength criterion, its static strength must be satisfied. The new fatigue strength criterion can be used in analyzing the boring bar’s fatigue strength on both complicated working conditions and also single working conditions. The mechanism of failure and destruction of boring bar on BTA deep hole drilling in generally actual working conditions were studied in this paper which are helpful to promote the service life cycle of boring bar in practice. Some rules are also derived to assess the dynamic performance of working boring bar, which structure parameters will be selected reasonably according to it.
Dependence of Structural Stress on Indium Bump Sizes in 8×8 InSb Focal Plane Array
Authors: Sun Li Gong , Meng Chao , Meng Qing Duan
Published: February 2011

Based on viscoplastic Anand’s model, the structural stress of 8×8 InSb array detector with underfill dependent on indium bump sizes is systemically researched by finite element method. Simulation results show that as the diameters of indium bump decrease from 36μm to 20μm in step of 2μm, the maximum stress existing in InSb chip first reduces sharply, then increases flatly, and reaches minimum with indium bump diameter 32μm. The maximum stress in Si readout integrated circuit (ROIC) fluctuates at 320MPa with amplitude less than 50MPa, almost half stress in InSb chip. Yet the maximum stress in the indium bump array is almost unchangeable and keeps at 16.3MPa. When the height of indium bump increases from 9μm to 21μm in step of 6μm, the maximal stress in InSb chip first reduces sharply from 800MPa to 500MPa, then almost retains constant. With indium bump diameter 32μm and height 21μm, the maximum stresses in whole 8×8 InSb array detector reaches minimum 458MPa, besides, the stress distribution at the contacts areas is uniform and concentrated, the stress value is smallest and this structure is promising to avoid device invalidation.
Debonding Analysis between FRP-Concrete Interface with a Linear Elastic Fracture Mechanics Approach
Authors: Qu Hong Chang , Chen Ling Ling , Zhang Sheng Li
Published: February 2011

A linear elastic fracture mechanics (LEFM) approach to the debonding analysis of concrete beams strengthened with externally bonded fiber-reinforced-polymer (FRP) strips are studied. The analytical models based on the LEFM approach are presented and discussed. The fracture analysis has adopted the energy-release-rate approach and the J-integral formulation. In addition, an algorithm for the construction of the equilibrium path that describes the debonding process in the FRP strengthened beam has been developed. The approach and its applicability to the debonding analysis of the FRP strengthened beam has been examined through three cases that include a single shear test, an edge peeling test, and a beam specimen strengthened with FRP. In cases where qualitative information regarding the initiation and progress of the debonding process is available, the LEFM model can be used for a reasonable quantitative appraisal of the debonding mechanism.
Study of Precision Formation on New Synchronizing Ring of Heavy-Duty Truck Based on Computer Numerical Simulation
Authors: Chen Jie , Yang Xiu Mei
Published: February 2011

Synchronizing ring, an important component of automotive synchronizer, uses the friction torque generated on its conical surface to synchro-mesh the two meshing components to realize gear shift. In the paper the forming of the hot precision forging of the new synchronizing ring is analyzed based on the finite element numerical simulation method, which provides evidence for processing optimization and mould modifying to get an accurate blank. In addition, the one-step forming processing for the synchronizing ring is analyzed, and the flow of the material, forming process, flaw prediction and the optimization of the mould structure is studied as well. The result indicates that it is more reasonable of the distribution of the material and it is more satiation filled of the cavities. The cycle life of new product development is reduced greatly by forming process analyzing and flaw prediction of the synchronizing ring.
Optimal Design of Plastic Injection Mould Gating System
Authors: Meng Ling Qin , Wang Zhi Wei , Liu Dan , Hao Wen Si
Published: February 2011

Taking the plastic injection mould of the air conditioning panel for example, through the flow simulation and analysis of the filling mould process for three gating system design programs, the paper gets each program’s filling time, temperature, shearing rate, melting wiring and air pocket, injecting pressure and the distribution map of locking strength. Through comparing and analyzing, the paper draws the relatively good design program, and finds the shaping defect that may appear ahead of time, which improves the success rate of once-testing mould so as to realize shorten mould design cycle and reduce mould manufacturing cost.
Analysis of Metal Flow and Deformation Features during Continuous Tube Rolling Process with Mandrel Mill
Authors: Yin Yuan De , Li Sheng Zhi , Kang Yong Lin , Hu Lan Wei
Published: February 2011

With the aid of commercial FE code MSC.SuperForm, the structural steel tube continuous rolling process of a typical hollow tube specification 152.5×12.5mm is simulated based on Bao Steel 152.5 main pass sequence of 140mm 8-stand mandrel mill, and the distribution characteristics of stress/strain, outline lateral spread, temperature changes of workpiece in continuous rolling process and distribution of stress/strain, friction of workpiece in deformation zone are analyzed. Analysis results indicate that deformation of workpiece along the width of the groove, especially at the top and the bottom of the groove is highly inhomogeneous due to the unequal draught and the longitudinal stress of special position (the top and the bottom of the groove) of workpiece is always an alternate state, in a tensile-compressive-tensile manner, and has a distinct rule. In the first stand, outline dimension of workpiece gradually increases during reducing process and early stage of wall thickness reduction, but it gradually decreases during middle-late stage of wall thickness reduction and tends towards stability at last. It is inhomogeneous that distribution of unit compressive stress and longitudinal strain of workpiece in deformation zone, and contact stress and total equivalent plastic strain are maximal in inner surface of workpiece contacting with mandrel. Temperature difference between the outer and the inner surfaces of workpiece is obvious.
Elastic-Plasticity Analyze of Bending Deflection on Profiled Bar Roller Straightening
Authors: Wang Hui Gang , Liu Xue Jiang , Liu Hai Sheng
Published: February 2011

It is difficult to get an engineering accuracy answer of bending deflection for the profiled bar roller straightening according to elastic-plastic mechanics theory. In this paper, adequate mechanics model of profiled bar is established, combined with computer and mathematics, the relation between force and bending deflection of the profiled bar roller straightening is deduced. Compared with the traditional and engineering method, it is shown that the analytic solution accords with the production conditions and straightening theory and is a important reference for the establishment of technological parameters.
The Simulation and Experimental Study of Metal Cutting Based on Cold Air Technology
Authors: Lin Qiong , Zhang Zhen Xiang , Wang Qiu Cheng
Published: February 2011

Metal Cutting based on cold air technology is a green manufacturing technology which has the potential of great application prospect. In order to study the influence of cold air technology on metal cutting characteristics, the experiment and FEM simulation of both 0Cr18Ni9 stainless steel and 45 steel were performed under three cutting conditions. The results are analyzed to reveal that with cold air technology the temperature of cutting area can be effectively reduced and the tool life, surface roughness and the shape of chip can be significantly improved. The study on metal cutting with cold air technology based on simulation has a relatively high reliability, which provides a novel approach for the research on metal cutting with cold air technology.
The Synthesis of Mg-Zn-Al LDH and the Sustained-Release Properties of Theophylline Intercalated LDH
Authors: Du Bao Zhong , Luo Wei , Wang Ru Min
Published: February 2011

Layered double hydroxides (LDHs), consist of cationic brucite-like layers and exchangeable interlayer anions. In this thesis LDHs consist of brucite-like layers of zinc hydroxide, with the exchanging propertity of interlayer anions in hydrotalcites, used Mg/Zn/Al-LDH as precursor to prepare the theophylline intercalation assembly hydrotalcites to obtain supramolecular complex for the first time by co-precipitation under a nitrogen atmosphere, determined the reaction conditions and influential factors of the synthesis of theophylline-pillared hydrotalcites, and tested its sustained-release performance in different media. The product has been characterized by powder X-ray diffraction (XRD), FT-IR spectroscopy, uv-vis spectrophotometer and thermogravimetry-Differential thermal analysis (TG-DTA) . Results demonstrated that : Through co-precipitation intercalation methods, with molar ratio of Mg/Zn/Al/ theophylline being 3:1:1:2, co-precipitation medium pH9, crystallization temperature 80 °C and crystallization time 12h can obtain the clear chemical composition and good crystallization of inorganic - organic hybrid-type drugs hydrotalcites. In addition, according to Pharmacopoeia measured the release rate of theophylline-LDH in the different media including distilled water,0.9%saline,simulated intestinal fluid (pH7.4 phosphate buffer) by UV spectrophotometry, Theophylline pillared hydrotalcite has a certain release in the media above all. And calculated the release of intercalation theophylline, lay the foundation for the further clinical application.
Explosive Compaction of Metallic Glass Particles Reinforced Aluminium Matrix Composites
Authors: Wang Jin Xiang , Zhang Xiao Li , Zhou Nan , Zhao Zheng
Published: February 2011

In this paper the metallic glass particles reinforced aluminium matrix composites without obvious defects were obtained successfully by explosive compaction of mixed powders. The mass fraction of the amorphous phase is 10%, 15% and 20% respectively in the specimens. The scaning electric microscope micrographs of the composites show that the metallic glass particles are uniformly distributed in the matrix. The x-ray diffraction and differential thermal analysis of the composite specimens show that the amorphous phase is maintained in the composites without crystallization during the compaction. Finally the influences of macro-temperature rise and micro-heat transfer on the crystallization were analyzed.
Consolidation of HLW into Mineral-Like Materials by the SHS
Authors: Zhang Rui Zhu , Li Yong , Zhang Yu Xin , Guo Zhi Meng , Su Wan Shan
Published: February 2011

Samples of mineral-like materials based perovskite and model high-level wastes (strontium) were fabricated by the SHS-densification and tested. The results of MCC-1, XRD and SEM/EDS analysis show that the major phase is well concordant with the design. The samples were characterized by dense structure and fine chemical stability. It is a durable material with high-level waste loading and is in favor for final geological disposal.
Superplasticity-Like Behavior, Microstructures and Deformation Mechanism Map in Superlight Mg-6Li-3Zn Alloy
Authors: Cao Fu Rong , Guan Ren Guo , Ding Hua , Li Ying Long , Zhou Ge , Cui Jian Zhong
Published: February 2011

Mg-6Li-3Zn alloy sheets were prepared by melting and casting, and heavy rolling with a total reduction of 94%. The high-temperature mechanical behavior, microstructures and deformation mechanisms were investigated. The maximum elongation to failure of 300% was demonstrated at 623K and an initial strain rate of 1.67×10-3s-1. Observations by optical microscope, transmission electron microscope reveal that significant dynamic recrystallization and grain refinement occurred in banded grains at 573K and an initial strain rate of 1.67×10-3s-1, under which the subgrain contour was ambiguous and dislocation distribution was relatively uniform. It is shown by newly constructed deformation mechanism map that the high-temperature deformation mechanism in Mg-6Li-3Zn alloy sheet with banded grains at 573K and an initial strain rate of 1.67×10-3 s-1 is dislocation viscous glide controlled by lattice diffusion, the stress exponent is 3 (strain rate sensitivity exponent 0.33) and deformation activation energy is 134.8 kJ mol-1, which is the same as the lattice diffusion activation energy of magnesium.
Application of Advanced Cooling Control System for Plate Mill
Authors: Wang Bing Xing , Tian Yong , Yuan Guo , Wang Zhao Dong , Wang Guo Dong , Chen Jun Ping
Published: February 2011

Based on the new generation TMCP technology, The State Key Laboratory of rolling and automation, Northeastern University(RAL) developed an advanced cooling system(ADCOS-PM). The system was combination of ultra-fast cooling (UFC) equipment with the advantage of high cooling intensity and homogeneous cooling and traditional accelerated cooling equipment(ACC). The UFC equipment was composed of jet impingement cooling device with high-pressure water and the ACC equipment was composed of laminar cooling device with good controllability. The control object of ADCOS-PM control system including finish cooling temperature and cooling-rate of every stage was controlled by adjusting the parameters such as the run-out table speed, state of active and inactive jet, flow rate of active jet. The temperature profile of plate was completed on the run-out table so that the product with fine microstructure and good mechanical properties was produced. The ADCOS-PM was built in 4300mm plate mill of Anshan Iron and Steel Co., Ltd. in 2010 and the recycling products with high-performance were produced.
Research on Flow Stress of Magnesium Alloy Sheet under Warm and High Strain Rate Forming Condition
Authors: Meng Zheng Hua , Huang Shang Yu , Hu Jian Hua
Published: February 2011

Process simulation is a powerful tool to predict material behaviors under specified deformation conditions, so as to optimize the processing parameters. The equation for flow stress is important to numerically analyze. However, the reported constitutive equations of magnesium alloy are only suitable for processing simulation with strain rate between 0.001-1s-1. In this paper, the strain-stress behavior of AZ31 under warm and high strain rate (>103s-1) condition has been investigated by split Hopkinson pressure bar experiments at elevated temperature. The results show that the influence of the temperature on flow stress is more obvious than that of strain rate; the flow stress decreases with the rise of temperature at a certain strain rate. Based on Johnson-Cook model, the constitutive equation of AZ31 magnesium alloy under warm and high strain rate condition has been given out by fitting the experimental data, which can be applied in process simulation of AZ31 magnesium alloy sheet forming.
Injection Mould Parametric Reusable 3D Parts Libraries of Development
Authors: Ping Zong Bao , Sun Wen Lei , Adayi Xieeryazidan , Guo Shu Jun , Pan Hong
Published: February 2011

The paper introduces injection mould 3D parts library parametric reusable technology development which is on the basis of UG. The built 3D parts library injection mould which uses VisualC + + 6.0 and UG/Open secondary developing tools can realize the injection mould parts of model parameter driving and reusable functionality. It can make mould designer directly call besides cores outside of the parts, improve the efficiency of the mould design and effectively shorten the development cycle of mould.
Stray Light Elimination Methods for Laser Communication System with Submarine
Authors: Li Hai Yan , Wang Lian Sheng , Liu Xu Dong
Published: February 2011

Submarine is an important part of modern military power, and communication with submarine is a key problem which needs solving. Blue-green laser communication system with submarine can improve the safe depth and communication speed of submarine greatly, and many countries have paid a lot of attention to develop laser communication system for a long time. The disturbance would communicate in the whole system if the stray lights exit and influence the signals on detector focus surface, and these will increase the BER and influence the communication ability. This optical receiver system adopting Ritchey-Chretien(R-C) Cassegrain structure of blue-green laser communication system with submarine is introduced firstly in this paper, and then the sources of stray light are analyzed detailedly. The corresponding elimination methods for stray light are proposed and according to the analysis, the further optimization can be carried out.
COF Measurement of Tubes by Hydraulic Bulging with Radial Crushing
Authors: Yang Lian Fa , Wu Cong Qiang , Chen Feng Jun
Published: February 2011

A new method of determining the coefficient of friction (COF) in expansion zone of tube hydroforming (THF) is proposed. The measuring method features that a round tube is hydro-formed into a square one by a radial compression accompanying a constant internal hydraulic pressure p, and the difference ΔL of the two diagonal lengths of the square section of deformed tube is taken as measuring index for COF. The relationships between the ΔL and the p, COF, relative displacement S/S0 of moving punches are established by the finite element (FE) simulation of the forming process. The COF can be determined by matching the indexes ΔL from experiments and simulation. The FE simulation results show that the measuring index ΔL is in exponent proportion to COF and the internal pressure p, it is extremely sensitive to the friction force or COF and conveniently measured and especially under a higher internal pressure.
Finite Element Simulation and Experimental Study of the Effect of Cone Parameter on Thickness Distribution in Hydroforming of Conical-Cylindrical Cups
Authors: Gorji Abdol Hamid , Bakhshi M. , Nourouzi S. , Hosseinipour S.J. , Mohammad-Alinejad G.
Published: February 2011

Forming conical parts is one of the complex and difficult fields in sheet metal forming processes; because of the low contact area of the sheet with the punch in the initial stages of forming, too much tension is applied to the sheet causing burst occurrence. Furthermore, since the major part of the sheet surface between the blank holder and punch tip is free, wrinkles appear on the wall of the drawn parts. Therefore, these parts are normally formed in the industry by spinning, explosive forming or multi-stage deep drawing processes. In this paper, the parameters in the process of hydroforming conical parts along with using finite element simulation and experimental procedures have been studied. The punch radiuses parameters (the punch tip radius and the radius between the conical and cylinder section and their effects on the bursting and thickness distribution were investigated.
Blank Thickness Effects on Rolling Force in Hot Rolling of Titanium Alloy Large Rings
Authors: Wang Min
Published: February 2011

For hot rolling of titanium alloy large rings, rolling force is very important for designing, choosing and optimizing of processing plan and rolling mill. In the paper, the average shape parameter of the deformation zone of ring rolling is presented first, and then a reliable coupled thermo-mechanical three-dimensional (3D) finite element (FE) model for the process is developed. Finally, influences of the blank outer radius R0 and inner radius r0 on rolling force are discussed and compared for exploring blank thickness effects. The main results show that decreasing the blank thickness by decreasing R0 or increasing r0 leads to a saving of rolling force, while R0 has a predominant effect than r0.
The Decomposition Mechanism of Titania Film with Nanotube Structure
Authors: Chen Chien Chon , Chen Shih Hsin , Chang Shao Fu , Kao Mann Juin , Jheng Wern Dare , Wang Shing Hoa
Published: February 2011

The ordered nanochannel-array of anodic titanium oxide (ATO) is formed on the electro-polished titanium substrate. This reproducible procedure of long-range ordered nanochannel ATO retains 170 nm films in length. The process is deduced by electrochemically and thermodynamically; from high defect structure of porous ATO and small sizing of decomposing TiO2cluster on the surfaces. In this study, ATO with 68.2% porosity is discomposed at 581 °C under oxygen partial pressure of 4×10-9atm. The pore of ATO has wall thickness of 25 nm with density of 8×109per cm2under 1.2 vol.% hydrofluoric acid (HF) and 10 vol.% sulfuric acid (H2SO4) electrolyte for 90 seconds of 20 V of applied potential. The pore size is 100 nm in diameter and uniformly distributed with 120 nm pore-to pore distance in between.
A Fault Diagnosis of Suck Rod Pumping System Based on Wavelet Packet and RBF Network
Authors: Wu Wei , Sun Wen Li , Wei Hang Xin
Published: February 2011

In order to diagnose the fault of the pump oil well, a fault diagnosis method based on the wavelet packet and the neural network is introduced. Firstly, the dynamometer card of the pumping well is gathered and normalized, then these data are decomposed by using three layers of wavelet packet. It makes up eight energy eigenvectors which are regarded as the input eigenvector of the RBF network. The experiment indicates that the method can not only detect the fault of the pumping oil well but also can recognize the fault type of it. It shows that the method is very effective for safety protection and fault diagnosis in the pumping oil well.
Numerical Simulation and Process Optimization for Multi-Stage Forming of Wheel Centre Disc
Authors: Cai Gan Wei , Xu Xi Yong , Zheng Zhan Guang , Zhang Zhuan , Wu Du Chao
Published: February 2011

The steel wheel centre discs are usually stamped by multi-stage sheet metal forming. The stage number and the content of every stage decide if the structure-pieces can be formed successfully and the final forming quality. In this paper, the forming characteristics of wheel centre disc were analyzed firstly and the reasonable two-stage stamping scheme of drawing and inverse-drawing are adopted. The numerical simulations of multi-stage stamping process are performed and connected together through deformation transmission. By means of FLD and changes of sheet metal chickness, the formability is analyzed and the forming process is optimized. The feasibility of multi-stage forming process simulation and the validity of the optimized scheme were verified by stamping in practice.
Control on Head Displacement of H-Beam in Rolling Process
Authors: Ma Jin Hong , Li Hui , Li Hong Bin , Zhang Wen Zhi
Published: February 2011

The uneven elongation between flange and web can make long tongue in the head of H-beam, which can lead to too long crop end length. In order to control the tongue length of H-beam head, different elongation ratio between flange and web is put forward to control the head displacement of H-beam. If the flange and web elongation is uniform, the loss of crop end length will be reduced. At the same time, different cooling speed of flange and web is set to keep the section uniform temperature. Experimental investigations of H-beam rolling are carried out on the universal mill in the Rolling Lab of Hebei polytechnic University. Comparisons between experimental value and simulation results prove the correctness of elongation ratio of flange and web.
Blank Optimization of Sheet Metal Forming Based on Response Surface Methodology
Authors: An Zhi Guo , Zhang Yu
Published: February 2011

The thickness variation of drawing part is usually very complicated, which causes the accurate calculation of the surface area of drawing part to be very difficult. Blank optimization of sheet metal forming is often considered as a multi-objective problem. A blank optimization strategy of sheet metal forming process was suggested based on Response Surface Methodology (RSM). Latin Hypercube Sampling (LHS) method was introduced to design the rational experimental samples; the objective function was defined based on crack factor and wrinkle factor; the accurate response surface for sheet metal forming problem was built by Least Square Method; Genetic Algorithm (GA) was adopted in optimization and Pareto solution was selected. The strategy was applied in blank optimization of an auto-part, this method was proved suitable for blank optimization of sheet metal forming.
Thickness Distribution in Conical Parts Formed by Hydroforming and Conventional Multistage Deep Drawing Processes
Authors: Gorji Abdolhamid , Yaghoubi Amir Reza , Bakhshi-Jooybari Mohammad , Norouzi Salman
Published: February 2011

Forming conical parts is one of the difficult fields in sheet metal forming processes. Because of low contact area of the sheet with the punch in the initial stages of forming, too much tension applied to the sheet that it causes bursting. Furthermore, since the major part of the sheet surface between the blank holder and punch tip is free, wrinkles appears on the wall of the drawn parts. These parts are normally formed in industry by processes such as spinning, explosive forming or multistage deep drawing. Hydroforming deep drawing is one of the special deep drawing processes which have been introduced in order to overcome some inherent problems in the conventional deep drawing with rigid tools. In the present work, an experimental program has been carried out to form and compare the forming pure copper conical-cylindrical cups by hydroforming and conventional multistage deep drawing processes. The conical parts in conventional deep drawing process formed in two stages. The results of the study demonstrate that thickness distribution are more uniform in the parts formed by hydroforming compared to conventional multi stages deep drawing processes.
The Effect of Purity of Zirconium Material on Mechanical Properties and Microstructure of Zr-Based Bulk Metallic Glass
Authors: Liu Guang Qiao , Kou Sheng Zhong , Li Chun Yan , Zhao Yan Chun , Suo Hong Li
Published: February 2011

Series of rod samples of Zr55Al10Ni5Cu30 alloy were prepared by magnetic suspend melting and copper mold suction casting method using 99.9wt% high purity zirconium and 99.4wt% low purity sponge zirconium respectively, the effect of purity of zirconium material on mechanical properties and microstructure of Zr-based bulk metallic glass were investigated. The result shows that high purity material alloy could enhance the thermal stability and glass forming ability of Zr-based bulk amorphous alloy, compression fracture surface analysis indicate that the vein patterns density increase with the material elements purity increase, the average compressive fracture strength is increased to 8.52% than that of low purity samples.
Consititutive Modeling for Auto-Body Steel Sheet Incorporating Strain Rate and Temperature
Authors: Wang Wen Ping , Wan Min , Wang Hai Bo , Wu Xiang Dong , Diao Ke Shan
Published: February 2011

Uniaxile tensile tests of auto-body steel sheet were performed at strain rate of 10-4 to 101s-1 and temperature of room temperature to 180°C. Strain rate and temperature sensitivity of flow stress were analyzed. It is found that the stress-strain curve is obviously heavily weighted on the temperature and strain rate. A new constitutive model was constructed and implemented into Abaqus/Explicit commercial software using user subroutine VUMAT. Verification of constitutive model shows that it has good agreement with experimental result.
Study on Direct Hot Isostatic Pressing Technology for Superalloy Inconel 625
Authors: Wang Ji Wei , Wei Qing Song , Liu Guo Cheng , He Yu Kun , Shi Yu Sheng
Published: February 2011

Inert gas atomized (IGA) superalloy Inconel 625 powder was consolidated by hot isostatic pressing (HIPing) directly under the HIPing parameters of 1100°C/110MPa/3h. The structure and properties of the as–HIPed samples were investigated using optical microscopy (OM), scanning electron microscopy (SEM) and tensile tests at room temperature, and its relative density was measured by drainage. The fracture surface morphology of the tensile specimens have been investigated using SEM. The results showed that full density alloy can be obtained under the HIPing parameters of 1100°C/110MPa/3h. Due to the effect of prior particle boundaries (PPBs), the strength of the as-HIPed alloy is comparatively high, but its ductibility is comparatively low.
Numerical Simulation on Efficient Spinning Technology Based on Multi-Point Adjusting Principle
Authors: Gong Xue Peng
Published: February 2011

In order to realize high efficiency and flexible manufacturing for rotary surfaces, efficient spinning technology (EST) is researched. It is the combination of multi-point forming and traditional spinning. Principle of EST is described, traditional spinning method is compared with it, and characteristics of it are analyzed. Finite element analysis (FEA) model of disc-shape part is established, EST process is analyzed, equivalent stress and plastic strain distributions are analyzed. EST equipment is developed, and the experiments are made. Results indicate: EST process consists of four stages; equivalent stress in sheet metal’s center region and bendable rollers active region exceeds yield stress, and plastic deformation is generated; experimental result accords with simulation result. Feasibility of EST is validated by simulation and experimental results.
Application of Taguchi Method in the Optimization of Cutting Parameters for Turning Metal Matrix Composite
Authors: Sriprateep Keartisak , Patumchat Puttipong , Theansuwan Wasan
Published: February 2011

The objective of this study was to utilize Taguchi methods to optimize surface roughness, tool wear and power required to perform the machining operation in turning metal matrix composites (MMC). The cutting parameters are analyzed under varying cutting speed, feed rates and cutting time. The settings of turning parameters were determined by using Taguchi’s experimental design method. Orthogonal arrays of Taguchi, the signal-to-noise (S/N) ratio, the analysis of variance (ANOVA) are employed to find the optimal levels and to analyze the effect of the turning parameters. Confirmation tests with the optimal levels of machining parameters are carried out in order to illustrate the effectiveness of Taguchi optimization method. The results show that the Taguchi method is suitable to solve the stated problem with minimum number of trials.
MQL Technology Including the BTA Deep Hole Drilling Machining
Authors: Peng Hai , Li Tong
Published: February 2011

The traditional cast-type method of BTA deep-hole drilling(such as BTA or DF) has cutting fluid consumption of the existence of large, high production costs, pollution of the environment and endangering the health of the operator and other problems. In this paper, the MQL technology (minimum lubrication technology) is applied to the method of BTA deep-hole machining (ie, near-dry deep-hole processing), we also analyzed the function and effect of MQL machining cutting fluid. Through the near-dry deep-hole drilling experiment, we find that a water-soluble cutting fluid has good atomization effect and the processing system also has fine effect of cooling and chip evacuation. We proposed mixed-use oil and the low-temperature cold spray methods to improve the tool lubrication and cooling effect for some great issues such as tool wear.
An Ultrasonic Elliptical Vibration Burnishing Process for Reducing Surface Roughness
Authors: Qin Wei , Zhang De Yuan
Published: February 2011

It is widely recognized that the chipless finishing process — the burnishing process can be used efficaciously to reduce the surface roughness of components. But most of previous works published concentrated on the conventional burnishing process and experimental researches in the last few years. There are some limitations on the conventional burnishing process in reducing surface roughness. Ultrasonic elliptical vibration burnishing (UEVB) process is proposed. Theoretical model is established to analyze theoretical surface roughness. Steel 45 was selected as material for making the specimens in the experiments and a new device developed by us was used for the burnishing process. The comparison shows that the surface roughness in describing the burnishing process is better than the conventional burnishing process obviously.
Study of High-Speed Machining Parameters on Nickel-Based Alloy GH2132
Authors: Gao Dong Qiang , Li Zhong Yan , Mao Zhi Yun
Published: February 2011

A model of stress and temperature field is established on nickel-based alloy cutting by finite element modeling and dynamic numerical simulating, and then combining high-speed machining test and orthogonality analysis method, the influence law of cutting parameters on the cutting force and tool wear has been researched, and the tool life and cutting force prediction model based on cutting parameters has been obtained. Finally, by genetic algorithm method cutting parameters are selected reasonably and optimized. The result shows that the bonding wear is main tool wear, and the influence of cutting speed on cutting force is smaller than feed per tooth and axial depth of cut.
Research on Higher Frequency, Short Pulses and Assisted Magnetic Field Electrochemical Machining
Authors: Jia Jian Li , Fan Zhi Jian
Published: February 2011

High Frequency Short Pulses current power and assisted magnetic field are adopted in the processing experiments of Electrochemical Machining(ECM), which can achieve small gap stable machining about thin-wall surface(10000mm2) of workpiece of aluminum alloy. The experiments show that shaped-surface dimensional deviation of finished workpiece is less than 0.05mm, dimension deviation in thickness ranges between 0.02 and 0.05mm, and surface roughness changes from 0.1 to 0.2μm on the condition that frequency is 1 kHz, duty ratio is 0.45 while voltage is 11V with the magnetic circuit embedded inside clamping fixture. The apparent improvement in machining gap flow field and the advancement in precision as well as surface quality of workpiece are attributed to the intermittence from pulses current, agitation from the pressure wave along with magnetic Lorenz force.
Research on Several Machining Processes of the up-down Abnormity Hole by WEDM
Authors: Wang Yuan , Liu Xue Yuan , Wang Ying Biao
Published: February 2011

WEDM is used to cut quenched and tempered 45 steel samples with up-down abnormity holes by conventional and improved machining process, and time-consuming by various processes is taken to be compared and analyzed. The results show: when cutting a up-down abnormity hole, one time of wire feeding and taking out is lessened and non-working time are effectively reduced by improved process than conventional process; machining processⅡ of two can effectively decrease working time, heat treatment stress releases before cutting straight hole so the final machining size and shape don’t change; the best machining effect can be obtained in cutting up-down abnormity hole by improved machining processⅡ.
Experiment Study of Oil-Air Lubrication on Cooling of Turning Tools
Authors: Wang Jin Li , Cai Lin , Zheng Hong Tao
Published: February 2011

When lubricants are used according to special requirements, it is possible to achieve considerable cost savings. Compared to conventional coolant cooling technology used in metal cutting, oil-air lubrication increases cooling performance, avoids environmental pollution, reduces running and maintenance costs. The cutting temperature contrast experimental research was based on close to practice 45# steel in dry cutting, wet cutting and oil-air lubrication conditions. The research work concentrated on the superiority of oil-air lubrication cooling and the influence of cutting amount on temperature. The experimental results show that oil-air lubrication is more effective in reducing the cutting temperature than wet cutting or dry cutting, this paper details the cutting temperature curves at several different tests provides a basis for industrial production, improves the level of machining process and the significance was being reported.
ICAI Realization Method for Parallel Robot Instruction
Authors: Tan Da Peng , Chen Shu Ting , Wang Ying Chun , Ji Shi Ming
Published: February 2011

This paper brought forward an intelligent computer aided instruction (ICAI) modeling method oriented to parallel robot instruction. According to the learning-origin structure of mechanical specialty students, the study process and cognition characteristics were analyzed, and the comparative research on their quality performance in parallel robot direction was carried out. The ICAI model was established oriented to parallel robot practical instruction combining machine learning and artificial intelligence method. Aiming at the basic instruction requirements of mechanical engineering specialty, the innovation mechanism of this area was researched, and the instruction strategies optimized and realization method were provided. Experiments proved that this method can simulate the implementation course of parallel robot instruction, and improve the instruction effects validly.
Research and Prospects of Improving the Fatigue Life of Wleded Train Bogie Structure
Authors: He Bo Lin , Yu Ying Xia , Liu Jing
Published: February 2011

Because of the high-speed, high transport capacity, low power consumption and a lot of technical and economic advantages, high-speed rail way are universal importance. High-speed railway with the speed of more than 300k/h has been run in China. But fatigue cracking of wleded bogie structure is markedly increased with increasing the train speed. How to avoid fatigue destroy of wleded bogie structure and ensure the safety of transportation are urgent problems to be soved in engineering. A lot of research works have been done at home and abroad. Comparing with traditional surface engineering method, there are many advantages of ultrasonic impact , for example, simple operation, less power consumption, high efficiency, adapt to a wide range, easy to achieve automate production and so on. It is an effective way to surface strengthening of metallic materials. Plastic flow and grain refinement on the metal surface can be obtained by using ultrasonic impact method, and the residual compressive stress on the surface can also be formed. So the mechanical properties of metal surface can be greatly improved. It is new method used in the area of welded structure, especially in the welded bogie structure. It is a new research direction to research the surface nanocrystallization mechanisium of ultrasonic impact, the effect of ultrasonic impac on the fatigue properties and failure mechanisium of wled joint of bogie.
The Effect of Carbon Content in Filling Alloys on η Phase Formation in the Interface Zone of YG30 and Weld Bead
Authors: Zhao Xiu Juan , Chen Chun Huan , Sun Yuan , Yang De Xin , Tagashira Kohsuke
Published: February 2011

The cemented carbide YG30 and steel 1045 were welded with Co-Fe-C filling alloys with different carbon contents by the tungsten-inert-gas (TIG) arc welding. η phase formation at the welding joints was investigated through scanning electronic microscopy (SEM). The results show that the average composition of η phase is W-25, Fe-22, Co-19, C-24 (mass, %), which is a kind of carbide enriched by Fe, W，and Co. The amount of η phase formed near the interface of YG30 and weld bead is related to the C content in the filling alloy. Namely the amount of η phase decreases with the increasing of the C content in the filling metal. When the C content reaches to 0.8 wt%, no η phase forms. The reason of which is that the added C reduces and/or restrains the resolving of the WC that locates at the interface, so that inhibit the W and C to form η phase with Fe and Co. The existence of large-size η phase near the interface is mainly attributed to the aggregation of small size η phase with the unsolved WC due to the stir of liquid metal, and then growing up.
Study on the Microstructure and Properties of Zl114a Friction Stir Welded Joint with Forced Cooling
Authors: Liu Ge Ping , Chen Yu Hua , Wu Hong Yan , Ke Li Ming
Published: February 2011

ZL114A was joined by friction stir welding and liquid nitrogen was used to cool the welded joint during the welding process. The Influence of forced cooling on the microstructure and properties of welded jointed was studied. The results show that, when forced cooling is used, the amount of silicon particles in weld nugget zone is larger and the size is more homogeneous, the size of silicon particle in heat-mechanical affected zone is more fine , the grain size of heat affected zone is half of air cooling welded joint and the amount of Al-Si eutectic is smaller than air cooling welded joint. The micro hardness increases after forced cooling is used, the hardness of weld nugget zone is 20Hv higher than air cooling welded joint. The strength of forced cooling welded joint increases 13.6% than air cooling welded joint.
Microstructural Characterizations of the 316 Stainless Steel-Alumina Joining by a Modified Moly-Manganese Process and Brazing
Authors: Kuo Dong Hau , Yeh Kai Ting , Shiue Ren Kae , Wei Ming Hsiung
Published: February 2011

The 316 stainless steel-alumina joining was prepared by a modified moly-manganese (Mo-Mn) process and a Ni net-embedded brazing method. The modified Mo-Mn process had a reaction layer between the Mo-Mn layer and the alumina substrate, followed by brazing with steel. The reaction products of the reaction layer with substrate and the Mo-Mn layer were investigated. The brazing method had a braze foil/compressed Ni net/braze foil set sandwiched between steel and alumina. The reactions among the Ni net, braze alloys and substrates were studied.
Research of Surfacing Technology on Continuous Casting Roller
Authors: Lin Jian Dong , Huang Ping , He Fan
Published: February 2011

For continuous casting roller with the poor Corrosion resistance, developed the PLJ225 flux-cored wire welding with nitrogen for continuous caster roller, flux of 107 matches, and used a suitable welding process for surfacing continuous caster roller. Continuous caster roll after surfacing not only has good resistance to abrasion, heat-fatigue resistance has a good performance, life expectancy increased by 1 ~ 6 times more.
Effect of Welding Heat Circulation on the Microstructure and Mechanical Properties of 500MPa Ultra Fine Grained Steel in HAZ
Authors: Zhao Hong Yun , Chen Bo , Zhou Li , Wang Guo Dong
Published: February 2011

Focusing on the need of actual production, physical analogue experiments were done on the 400MPa ultra fine grained steel under different welding heat circulations. The experiment results showed that grains growing up and performance dropping was inevitable, the coarsening temperature range was 1000~1200 ; where the heating temperature was 800 in the Heat Affected Zone, the soften was the most obvious, but when the cooling rate t8/5<10s, the soften disappeared; speeding up the cooling rate could improve the microstructure of the Heat-affected Zone effectively and made the mechanical properties of the joint better than that of the base metal.
Review of Dynamic Reliability Analysis on Wind Turbine
Authors: Liu Hai Qing , Liu Lin
Published: February 2011

It’s significant to analyze the dynamic reliability of wind turbine in order to assure the safe and stable operation of wind turbine. In this paper, the dynamic reliability of wind turbine is analyzed with the propeller-type generator as example. The stability of blade of wind turbine under wind load is analyzed by calculating the fatigue load on blade. The frequencies of bending free vibration and torsion vibration of tower are summarized. Finally, the type of foundation and its simplified model are instructed and some useful conclusions are given for supplying basic information on dynamic performance of wind turbine.
Research of Material Flow for Friction Stir Welding Using Smooth Pins Based on Plasticine Analog
Authors: Xiao Ji Sheng , Xia Chun , Li Jian Ping , Ke Li Ming , Xing Li
Published: February 2011

Material flow during friction stir welding is very complex and not fully understood. Most of studies in literature used threaded pins. However, analyzing material flow using smooth pins is of great interest for the validation of a numerical model in which threads are difficult to represent. In this study, FSW experiments were performed using smooth pin based on plasticine analog. Longitudinal, horizontal and transverse sections of welds were observed with the use of plasticine of identical type but different color as material marker to investigate the material flow. A horizontal ‘vortex-like’ action has been occurred. In the agitating-extruding region (inside the pin diameter), a clockwise (identical to the rotating tool) layer appears around the tool, as a result the material both the advancing side and retreating side is mixed. In the deformation region (outside the pin diameter), the material is driven by the clockwise viscous force of the rotating pin, and the effect is reduced with the increase of the distance to the weld center.