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    25 June 2009, Volume 20 Issue 12
    Theoretic Parse and Experimental Study on Rolling-slipping Compound Passive Joint
    Chen Chun,;Huang Yumei;Shi Houqiang;Han Xuzhao
    2009, 20(12):  0-1390. 
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    A kind of rolling-slipping compound passive joint with the characteristics of bearing rolling pair and paste-plastic slipping pair was studied and designed.It can enhance the moment bearing capability and motion stability of passive joints used for parallel mechanisms.An analytic solution method for the deformation of the joint was established,which forms the basis
    for the design of passive joints.Analytic calculation and experimental test for a rolling-slipping compound passive joint were carried out.The application method of the joint was given out and the joint is used in the hybrid NC machine tools.

    Experimental Investigation on Fatigue Life of the Cross Univesal
    Driveshaft by Improving Crown Drop a Needle Roller
    Hua Tongshu,;Chen Xiaoyang;Xiang Pujiang;Li Xiong 
    2009, 20(12):  0-1511. 
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    The crown drop of a needle roller decides the pressure distribution between roller and raceway, capability and life of the universal driveshaft of the cross.
    It had been made that the experiment for research on fatigue life of cross univesal driveshaft by existing the needle rollers of the cross axle bearing with different crown drop. It
    is shown that experimental and the theoretical analyses have a better consistency and that there is reasonable value under certain working condition.It is possible to profile the needle rollers axially until the longitudinal pressure distribution is neither any “edge effects”nor high-pressure concentration at the center part of contacts. As a result the fatigue life of the univesal driveshaft is improved.

    Reserch on Printed Circuit Board Electronic Components Dismantling Model and Experiments
    Song Shouxu;Zhong Haibing;Zhang Hongchao
    2009, 20(12):  0-1390. 
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    The factors of dismantling force for surface mount devices(SMD) and through hole devices(THD) were analyzed, and the dismantling force model for SMD and THD was established by viscous fluid mechanics principle and material mechanics theory.The minimal dismantling forces of the above mentioned two kinds of components
    were also calculated,and the results of dismantling experiments show that this model is reasonable. The experiments indicate that horizontal dismantling force of SMD is more greater than vertical dismantling force, and the bend level and quantities of leg wire are the key factors of THD’s dismantling force, meanwhile the two kinds of components should be treated separately during the dismantling process.

    A Method to Measure Vertical Axis Roll Angular Errors of Machine Tool Based on Laser Interferometer
    Yang Xingang;Huang Yumei;Zhu Dexiang;Bao Baojun
    2009, 20(12):  0-1511. 
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    A method for roll angular error measurement of NC machine tool vertical axis was studied based on straightness measurement using laser interferometers system.First,a measuring model of roll angular errors was established using homogeneous transform matrices after analysis of relationship of measured data and primary errors.Then,on the basis of analyzing the principle of straightness laser interferometric
    measurement and adopting electronic level as relative orientation reference datum,a method and an equipment scheme for roll angular error measurement were proposed.Finally,a case study of horizontal axis roll angular error measurement following the principle of the method was carried out,whose testing results were compared with that of using electronic level and the
    results of the two different methods have little difference.The method and the equipment
    scheme are also suitable for roll angular error measurement of tilt axis in vertical plane.

    Ratio Control Strategy of CVT on Lagging Characteristics
    He Ren;Xia Jingjing;Zhang Yong;Wu Haixiao;Hou Suli;Ma Chengguang
    2009, 20(12):  0-1390. 
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    The influence of the lagging characteristics of CVT ratio control on the drivability and fuel economy of the automobile were studied.Based on the routine control strategy,the rotate speed signals of the secondary pulley were corrected, the algorithms of the objective ratio were perfected, and the departure of the engine operation from the optimal operation line was decreased. The drive signals of the ratio control valve
    were corrected based on the engine throttle valve opening response speed, the shift speed was perfected, and driving performances were improved. The minimum fuel consumption and the driving performance were unified by the engine throttle valve opening response
    speed. The experimental data shows that the corrected control strategy can improve the drivability and fuel economy of automobile.

    Study on Damage Phenomenon of Pharmaceutical Granule in Swirling Pneumatic Conveyance
    Li Yi;Yang Guangyou;Zhang Daode;Zhang Zheng
    2009, 20(12):  0-1511. 
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    The effects of swirling flow upon damage phenomenon of pharmaceutical granule were investigated by performing the vertical pneumatic conveyance of pharmaceutical granule experimentally. It is found that granules are conveyed along the pipe wall in weak swirling flow and the damage of granule can be reduced evidently at lower air velocity in this study. Numerical simulations show that the number of impact between granule and pipe wall in the swirling flow is larger than that in the rectilinear flow in all states of transportation, but at the time of impact between granule and pipe wall, the kinetic energy loss of granule is smaller in the swirling flow than in the rectilinear flow at lower air velocity. It is inferred that swirling flow can makes the granule move along the pipe wall and reduce the kinetic energy loss of granule to below the threshold of damage strength of the granules.

    Research on Climbing Step Capacity of RMERS 
    Zhang Liping,;Ma Shugen,;Li Bin;Zhang Zheng
    2009, 20(12):  0-1390. 
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    Based on the RMERS’s (self-reconfiguration modular exploration robots system) working principle and its child-robot’s motive mechanics, this paper researched the RMERS’ climbing step capacity in detail. For a child-robot,the method of exerting reverse velocity and planning its arm’s pose were adopted to make it climb up the step smoothly,thus the child-robot’s overstepping ability was strengthened. New robots system composed of some child-robots greatly expands the single child-robot’s circumstances adaptability.All configurations of the child-robot were analyzed,it is concluded that the loop connection is the best form in climbing step, and that decision-making method according to circumstances was put forward. When the step obstacle is little, the new system will overstep altogether,on the contrary, the strategy for sending a single child-robot pass to carry out the exploration role is adopted. At the same time, according to the static analysis, this paper analyzed the biggest step for the single child-robot and their connected system respectively. The corresponding experiments validate the analyzed results.

    Research on Vibration Characteristics of Air Spring with Auxiliary Chamber Based on Complex Stiffness
    Wang Jiasheng;Zhu Sihong;He Liang
    2009, 20(12):  0-1511. 
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    The dynamics equations of air spring system with auxiliary chamber were established,and the complex stiffness model of the system was deduced according to the equations being linearly processed. Based on the complex stiffness model,the calculation models of the system’s equivalent stiffness, equivalent damping and natural frequency were established. Firestone 1T15M-2 air spring was selected as a research object,the calculation models were amended and verified by test,and the results of test and calculation are close to each other.The calculation results show that,with the increase of orifice diameter,the system stiffness increases,and the system damping ratio firstly increases
    and then decreases;Enlarging auxiliary chamber’s volume can decrease stiffness and increase damping ratio. Increasing actuator frequency will increase stiffness and decrease damping ratio. The change of static load has little effect on vibration characteristics of the system.

    Estimation of Crack Expansion Life of Bar V-shaped Notch Tip under Variable Amplitude
    Load
    Zhang Lijun;Xiang Hengfu;Zhao Yongrui;Zhao Shengdun
    2009, 20(12):  0-1390. 
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    In order to calculate the crack expansion life in the action of variable amplitude load for the metal bar with V-shaped notch, the formula of bar fracture frequency was obtained theoretically by setting a size of bar fracture region applied in the engineering. Based on it, the mathematic expression of crack expansion life of bar V-shaped
    notch tip in the action of variable amplitude load was built.The influences of the durative time of every step variable frequency and the value of every step frequency change on the crack expansion life were analyzed in detail.To solve the influence of the resonance effect of the cropping machine on the crack expansion life,the resonance factor was proposed
    herein.The cropping experimental results for 45 steel bar and 20 steel bar show that the cropping time obtained by the formula of the crack expansion life proposed is consistent with the practical one on the whole.

    A MOGA-based Algorithm for Sequencing a Mixed-model Fabrication/Assembly System
    Wang Binggang;Rao Yunqing;Shao Xinyu;Xu Chi
    2009, 20(12):  0-1511. 
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    This paper is concerned about how to optimize the input sequences in a pull production system which is composed of one mixed-model assembly line
    and one flexible parts fabrication line. Two objectives were considered simultaneously:minimizing the total variation in parts consumption in the assembly line and minimizing the total setup time in the fabrication line.The mathematical models were presented. A multi-objective genetic algorithm (MOGA) was proposed for solving the model, in which a three-phase
    real number encoding method was put forward and the Pareto ranking method and the sharing function method were employed to evaluate the individuals’ fitness, which
    guaranteed the dispersity and uniformity of the solutions.The feasibility and efficiency of the MOGA are shown by comparisons with a genetic algorithm (GA) over the two single
    objective respectively.The computational results show that satisfactory results can be obtained by the MOGA. 

    Design of Flow Field for Finishig Spiral Bevel Gear in Pulse Electrochemical Finishing
    Adayi Xieeryazidan;Zhou Jinjin;Pang Guibing;Xu Wenji
    2009, 20(12):  0-1390. 
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    In order to enhance the machining quality of spiral bevel gear (SBG), it was presented that a new method of finishing SBG in pulse electrochemical finishing (PECF). So that, the influence of some factors of flow field on the finishing effect was studied herein. The experimental result show that the machining quality of SBG can be advanced efficiently to some extents. The SBG with surface roughness Ra=0.1μm and machining precision DIN 7 is obtained from a poor machining quality(DIN 7) in a period of finish machining by using Gleason milling machine №16.

    Orthogonal Design-based PID Control and Optimization of Capacity Scalability in Reconfigurable Manufacturing System
    Wang Lei;Tang Dunbing 
    2009, 20(12):  0-1511. 
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    Aiming at the disadvantage of the traditional manufacturing system which can not meet the dynamic market demands well, a multi-feedback adaptive
    dynamic model of the capacity scalability in reconfigurable manufacturing system was established.The PID controller was designed to optimize the system,and the PID parameters were made a further optimization by orthogonal design in order to get much better control parameters.An example was given and the results indicate that the controller designed by orthogonal design is effective and feasible, so it provides an effective approach for reconfigurable manufacturing system to adapt the dynamic market demands all the time.

    Stochastic Scheduling Algorithm for Multiple Mould and Die
    Manufacturing Projects Based on Multi-step Q Learning
    Zhang Shaqing;Chen Xindu ;Chen Qingxin;Chen Xin
    2009, 20(12):  0-1390. 
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    Through the analysis of uncertainties of the durations, costs,
    rewards as well as the characteristics of frequent repair in mould and die manufacturing projects with new potential projects randomly emerging,this paper proposed a stochastic evolution model of multiple mould and die manufacturing projects,which was on the basis of a discrete time Markov chain.With the aim to overcome the curse of dimensionality’,an algorithm combining parallel simulation of heuristic policies and multi-step Q
    learning was put forward to solve the above stochastic dynamic programming model.
    Finally,such an algorithm was explained with a sample example.The results show that the model is applicable and the algorithm is reliable and effective as well.With multi-step
    Q learning method,convergence speed can be effectively improved in the above algorithm compared with standard Q learning method.

    Research on Three-dimensional Hiberarchy Evaluation Model of 

    Customer Satisfaction Based on Grey Relational Analysis
    Li Fengping;Zhou Yuqing;Fu Peihong;Xue Wei 
    2009, 20(12):  0-1511. 
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    According to the difference of the weight of indexes and customer contribution and the comparability of products,an evaluation model was built based on three-dimensional hiberarchy of indexes-customers-products.And the evaluation
    arithmetic was described by grey relational analysis. The requirements of different
    customers can be distinguishable and customer satisfaction of different products can be
    contrastive by this method. And through analysis and calculation in the pump manufacture industry, the three-dimensional hiberarchy evaluation model of customer satisfaction based on grey relational analysis was demonstrated availably.

    Simulation Analysis on Cracks Detection Based on RFEC in Long-distance Oil and Gas Pipeline
    Wu Dehui;Huang Songling;Zhao Wei;Xin Junjun
    2009, 20(12):  0-1390. 
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    According to the principles of finite element(FE),a simulation model of RFEC was established to analyze the detection process for pipeline cracks.First, the axisymmetric mathematic model of RFEC was derived from the Maxwell’s equations, through which the radial propagation characteristics of
    the magnetic field on the surface of the pipeline were analyzed. Then the model of RFEC was optimized by Zoom-In’ in ANSYS to decrease its size, and the axial distribution of the magnetic field on the internal surface of the pipeline was evaluated. Finally, the detection signals corresponding to different cracks were calculated by the simulation
    model, and the relations between their phases and the geometric parameters of the cracks, such as depth, width and etc, were discussed. All the simulation results were represented
    herein and may be as a reference for the practical RFEC inspection of cracks.

    Research on Side Mill Way Planning Algorithm of Centrifugal Impeller Blade Ruled Surface
    Yang Chaoying;Yu Daoyuan;Yan Juan;Li Suke;He Shilin
    2009, 20(12):  0-1511. 
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    Based on gazing points method, tool-path planning method for five-axis flank milling of centrifugal impeller blade ruled surface with coned cutters was implemented.Firstly,basic tool axis vectors were generated. Then discrete gazing points in every tool position can be obtained. These points can constitute the enveloping surface when the cutter’s surface was moving along its trajectory. Error control method
    was given in order to describe the enveloping surface. Taking advantage of the designed ruled line and considering the interpolation overall errors in contact points,an innovative simple approach to calculate the errors was developed.The solution algorithm of shortest path in network chart was used to optimize the tool position with minimized errors. Integrity optimization algorithm for flank milling were established. Examples were given to illustrate the usefulness of this approach, along with simulation and error analysis.

    Application of DFAR Model to the Trend Prediction of Fault in Rotary
    Machines 
    Zuo Yunbo;Wang Xibin;Xu Xiaoli
    2009, 20(12):  0-1390. 
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    Aiming at the feature values of vibration signals of rotary machines,which sometimes have non-stationary and nonlinear development characteristics,DFAR (differential functional-coefficient autoregressive) model was presented.DFAR established nonparametric prediction model by using functional-coefficient autoregressive model.
    It automatically selected fractional or integral difference to process the original data and
    estimated the optimal model parameters according to the improved cross-validation criterion.The functional-coefficient autoregressive model can make the model parameters change with the model dependence variable.The fractional difference can extract the stable trend information from time series and it won’t lose low frequency because it has no defect of over-difference.So,DFAR can approximate the nonlinear time series better.As shown in the experiments,DFAR can improve the precision of predicting development trend of the non-stationary and nonlinear fault feature values.

    Mechanics Model of a Kind of Novel Damper Based on SMA’s Superelasticity
    Shen Wenqiu,;Han Yulin;Sun Zhilin;Li Aiqun;Wang Shilong
    2009, 20(12):  0-1511. 
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    Based on superelasticity of shape memory alloy (SMA), a new type of damper device was developed for vibration control implementation of cable like structures’ vibration control. This kind of damper could control the vibration of cable and pole like structures in all directions which were vertical about the axis of cables or poles. A mechanics model of such a reduced-scale SMA damper was performed. The formula of the output damping force and displacement was obtained for this kind of SMA damper based on the established mechanics model. Data, in detail, of three reduced-scale damper model were presented. 

    Dynamic Hysteresis Preisach Model of a Piezoceramic Actuator 
    Based on Asymmetric Exponential Function Hysteresis Operators
    Li Li;Liu Xiangdong;Hou Chaozhen;Lai Zhilin
    2009, 20(12):  0-1390. 
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    This paper proposed an asymmetric exponential function hysteresis operator, whose shape parameters were related to the input rate, so the shape of the new operator is variable and asymmetric. A dynamic Preisach model was built based on the new operator, and identified by the neural network. The experimental results show that the new dynamic model can describe the dynamic hysteresis of the piezoceramic actuators accurately. Under multi-frequency signals, the mean square error predicted by this new model reduces more than 0.20, and the max absolute error reduce more than 0.84μm, when compared with the double-S function hysteresis model.

    Study on Ceramic Grinding Crack Propagation 
    Mechanism under Ultrasonic Action by Using Nonlocal Theory
    Ma Hui;Zhao Bo,;Xie Ping;Yan Yanyan
    2009, 20(12):  0-1511. 
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    This paper presented a research of the attenuation of cyclic stress amplitude and the variation of microstructure under the action of ultrasonic vibration in crack propagation for Al2O3-ZrO2 composite nano-ceramics. To interpret this phenomenon, the nonlocal theory was introduced to establish the constitutive model under the ultrasonic condition based on the specified 2D attenuating function. The mechanics behavior of the ceramics under the action of ultrasonic vibration was analyzed according to the relationship between the internal characteristic length and the external characteristic length i.e. ultrasonic wave length. In addition, the variation law of the cyclic stress amplitude and microstructure with different ultrasonic frequencies was also studied. It is shown that the cyclic stress amplitude is attenuated under the action of ultrasonic vibration, and this attenuation phenomenon becomes more and more evident by increasing the ultrasonic frequency. The results of experiments are in accordance with the theoretical conclusions drawn from the nonlocal theory,which verifies that the action of ultrasonic vibration can actually accelerate the ceramic crack propagation. 

    Study on Characteristics of New Type Hypocycloid Energy Transformation
    Mechanism
    Xue Yunfeng;Du Qungui;Zhu Junpeng 
    2009, 20(12):  0-1390. 
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    Based on hypocycloid characteristics and transmission principles, a new kind of hypocycloid energy transformation mechanism was proposed.And its structural design was completed based on structure of a S195 type diesel engine.Virtual prototype model of the new type hypocycloid internal combustion engine was built by Solidworks and ADAMS software. And research on its kinematics and dynamics was conducted. The results show that compared with traditional mechanism of crank and connection rod, the piston of the new mechanism has longer residence time near top dead center, and it is more approach to top dead center at the same crank angle. So the fuel combustion can be done fully and the economy of internal combustion engine is improved. Simultaneously, fully straight movement of piston can be realized using the new mechanism, and lateral pressure of piston can be reduced greatly. And it is favor of reducing the friction losses, increasing the mechanical efficiency and decreasing its mechanical vibration and noise.

    Analysis of Continuous Extrusion Capability for Copper Bus Bar
    Song Baoyun;Cao Xue;Fan Zhixin;Liu Guilin
    2009, 20(12):  0-1511. 
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    In order to investigate the relationships among the expanded extrusion capacity of continuous extrusion for copper bus bar and the billet diameter, friction condition and structure parameters of chamber and die, the expanded deformation zone of billet was divided into two sub-zones according to the deformation characteristics of billet in the expanded die chamber. The analytic equations about the unit force at the chamber inlet were established by analysis with upper bound method. Laws about the effects of friction conditions, billet diameter, product width and thickness on unit pressure at the chamber inlet were obtained by programming calculation. The results show: the extrusion force increases linearly with the increase of product width, and decreasing product thickness can cause the rapid increase of extrusion force; the maximum width of product can be expanded obviously and the minimum thickness can be thinner by increasing feedstock diameter; taking the carrying capacity of tools and die as conditions, the product standards that can be produced by different diameter feedstock are obtained.

    Parameter Design and Performance Analysis for Three-degree Freedom Hybrid
    Magnetic Bearing with Bilateral Magnetic Pole Faces
    Wu Qinghai;Zhu Huangqiu 
    2009, 20(12):  0-1390. 
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    The configuration and magnetic suspension forces of an innovated three-degree freedom bilateral magnetic pole face hybrid magnetic bearing(HMB) were introduced.The flux path was calculated by using
    equivalent magnetic circuit,the mathematics models of the radial and axial magnetic suspension forces were deduced.The displacement stiffness and current stiffness were derived by linearizing the mathematics models.The methods on parameter design and calculation of the innovated magnetic bearing were presented in detail,such as gap magnetic induction intension,available area of magnetic pole,ampere-turns of control coils,and so on.
    The experimental prototype was designed in software ANSOFT,and its parameters of this magnetic bearing were given.The configuration and magnetic path of the experimental
    prototype were analyzed by using 3D-FEM.The coupling characteristics of movement and magnetic circuits among three degrees round balanceable position were analyzed by software MATLAB and 3D parameterization method.The research results show that the mechanical structure and magnetic circuit of this kind of magnetic bearing both are legitimacy.
    The methods on parameter design and calculation are feasible.The designed three-degree freedom bilateral magnetic pole face HMB prototype satisfies performance requirements.

    Collaborative Calculation of Coupled Structural Parameters for Collaborative Top-down Assembly Design
    Zhang Shuting;Gao Shuming;Yang Youdong,;Chen Xiang
    2009, 20(12):  0-1511. 
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    An approach was presented for the collaborative calculation of coupled structural parameters during collaborative top-down assembly design.To meet the requirements of the collaborative calculation of coupled structural parameters which were imprecise and distributed, triangular fuzzy numbers were adopted to represent the imprecise parameters and utility functions were utilized to express the designers’ preferences which reflected their knowledge and experiences.The designers collaboratively established the optimization model which took utility as the objective.Genetic algorithm
    was used to solve the optimization model.The approach was verified through an example of collaborative calculation of coupled structural parameters during the collaborative top-down design of a manipulator.

    Reliability Analysis on Mechanism Dynamic Strength Based on Assur-Group Method
    Zhang Chunyi,;Bai Guangchen
    2009, 20(12):  0-1390. 
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    Taking the component sectional sizes,the material strength and
    the material density as the random variables, and based on the movement analysis and the dynamic analysis while taking the Assur-Group as the unit,a general method of mechanism dynamic strength reliability analysis was established.As an example,the crank-slide mechanism was analyzed by using the method of MFOSM(mean first order second moment).The reliability curves were attained.The result indicates that this method is easy to popularize and has good universal property.It can be used in scientific research and the engineering practice.

    An Algorithm on Laser Measurement Model of 
    Ultra-precision Motion Stage and Error Compensation
    Teng Wei ;Zhou Yunfei;Mu Haihua;Yang Liangliang
    2009, 20(12):  0-1511. 
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    The reasons of Abbe error and cosine error were analyzed in laser measurement.Then the effect of Abbe error and cosine error on measurement optical path was discussed as two instances: an ideal model of interferometer without rotation & tilt and a non-ideal model of interferometer with them.The optical path was calculated separately. Next, a model whose x-y translation value will not be affected by the tilt & rotation of motion stage and a 5-DOF laser measurement algorithm were concluded. Finally, experimental results demonstrate the effectiveness and reliability of the proposed algorithm.The presented algorithm has been applied in semiconductor manufacturing equipment successfully.

    Application of a New Method for Strain Measurement in Complex Forging
    Li Feng;Liu Xiaojing;Li Chao;Shi Liansheng
    2009, 20(12):  0-1390. 
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    In order to solve the difficulties in analysing the behaviour of metal flow quantitatively in forging.A new method, screw method for strain measurement
    was used inside plastic deformation body.Based on the study of compressor impeller,a set of dies were designed, and the female die was assembled with four die sections.At last, the impeller was formed by isothermal precision forge.Using this method,four typical flow lines, axial strain and radial strain were measured during forming of the compressor impeller.The quantitative results of strain distribution were obtained.This method is an effective technique to analyse metal deformation behavior and strain distribution during die forging.It
    can be used to study material flow and to predict strain distribution in general bulk metal forming.