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Electrode Wear Prediction in Milling Electrical Discharge Machining Based on Radial Basis Function Neural Network

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Journal of Shanghai Jiaotong university(Science) 2009年第6期14卷 736-741页

作者：黄河白基成卢泽生郭永丰 Department of manufacturing and Automation Engineering Harbin Institute of Technology

Milling electrical discharge machining(EDM) enables the machining of complex cavities using cylindrical or tubular *** ensure acceptable machining accuracy the process requires some methods of compensating for electrode *** to the complexity and random nature of the process,existing methods of compensating for such wear usually involve off-line *** paper discusses an innovative model of electrode wear prediction for milling EDM based upon a radial basis function(RBF) *** gained from an orthogonal experiment were used to provide training samples for the RBF *** model established was used to forecast the electrode wear,making it possible to calculate the real-time tool wear in the milling EDM process and,to lay the foundations for dynamic compensation of the electrode wear *** paper demonstrates that by using this model prediction errors can be controlled within 8%.

关键词： milling electrical discharge machining (EDM) electrode wear prediction radial basis function (RBF) neural network

Effect of Heat Treatment on Microstructure and Mechanical Properties of Multiscale SiC_p Hybrid Reinforced 6061 Aluminum Matrix Composites

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 174-181页

作者：吴健铭许晓静 ZHANG Xu LUO Yuntian LI Shuaidi HUANG Lin institute for Advanced manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The performance of solid solution aging treatment on aluminum matrix composites prepared by powder metallurgy and reinforced with 6061 aluminum alloy powder as matrix;meanwhile, nano silicon carbide particles(nm Si Cp), submicron silicon carbide particles(1 μm Si Cp) and Ti particles were studied. The Al/Si Cp composite powder was prepared by high-energy ball milling, and then cold-pressed, sintered, hotextruded, and then heat-treated with different solution temperatures and aging times for the extruded composites. Optical microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy(EDS), X-ray diffractometer(XRD) and extrusion testing were used to analyze and test the microstructure and mechanical properties of aluminum matrix composites. The results show that after the multi-stage solid solution at 530 ℃×2 h+535 ℃×2 h+540 ℃×2 h, the particles are mainly equiaxed grains and uniformly distributed. There is no reinforcement agglomeration, and the surface is dense and the insoluble phase is basically dissolved. In the matrix, the strengthening effect is good, and the hardness and compressive strength are 179.43 HV and 680.42 MPa, respectively. Under this solution process, when the aluminum matrix composites are aged at 170 ℃ for 10 h, the hardness and compressive strength can reach their peaks and increase to 195.82 HV and 721.48 MPa, respectively.

关键词： aluminum matrix composites Si C particles multiscale hybrid enhancement heat treatment mechanical properties

A Phase Space Reconstruction Based Approach to Throughput Prediction in Semiconductor Wafer Fabrication System

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Journal of Donghua University(English Edition) 2010年第1期27卷 81-86页

作者：吴立辉张洁 institute of Computer Integrated manufacturing Shanghai Jiaotong University

In order to manage and control semiconductor wafer fabrication system (SWFS) more effectively,the daily throughput prediction data of wafer fab are often used in the planning and scheduling of *** this paper,an artificial neural network (ANN) prediction method based on phase space reconstruction (PSR) and ant colony optimization (ACO) is presented,in which the phase space reconstruction theory is used to reconstruct the daily throughput time series,the ANN is used to construct the daily throughput prediction model,and the ACO is used to train the connection weight and bias values of the neural network prediction *** with factory operation data and comparing with the traditional method show that the proposed methodology is effective.

关键词： daily throughput prediction phase space reconstruction artificial neural network

Comparative Assessment on Microstructure and Properties of in-situ TiC+Ti_(5)Si_(3)Reinforced TiAl-Sn-Zr Matrix Composites by Spark Plasma Sintering and Argon Protected Sintering

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Journal of Wuhan University of Technology(Materials Science) 2023年第1期38卷 199-205页

作者：姚辉许晓静 CAI Chengbin LI Chen CHEN Fenghua LIU Yangguang XIAO Yishui institute for Advanced manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The effects of SiC particles(SiCp)on high temperature oxidation behavior of titanium matrix composites(TMCs)under different powder metallurgy processes were *** situ Ti C+Ti_(5)Si_(3)reinforced titanium matrix composites were prepared by discharge plasma sintering(SPS)and argon protective sintering(APS).The results show that the two processes have a negligible effect on the composition and hardness of the samples,but the hardness of the two samples is significantly improved by adding *** apparent porosity of SPS process is obviously smaller than that of APS process,whereas,the apparent porosity increases slightly with the addition of *** oxide layer thickness and mass gain of the samples obtained by SPS process are smaller than those obtained by APS *** oxide thickness and mass gain of both processes are further reduced by adding *** SPS composites showed the best high temperature oxidation ***,TMCs with Si Cp by SPS can effectively improve the high-temperature oxidation behavior of the materials.

关键词： powder metallurgy titanium matrix composites High-temperature oxidation TiC and Ti_(5)Si_(3) Ti-Al-Sn-Zr

Hot Corrosion Resistance of TB8 Titanium Alloy after ECAP and Heat Treatment

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1440-1448页

作者： LI Shuaidi XU Xiaojing BAI Xiang CAO Bin institute of Advanced manufacturing and Modern Equipment Technology Jiangsu UniversityZhenjiang 212013China

The metastableβtitanium alloy TB8(Ti-12.76Mo-2.13Nb-2.73A1-0.16Si)was used as the original material,and the secondary processing method combining equal channel angular pressing(ECAP)and heat treatment was *** the help of optical microscope(OM),scanning electron microscope(SEM)and X-ray diffractometer(XRD),the corrosion behavior of TB8 titanium alloy after different secondary processing(800℃/850℃solid solution-520℃aging,ECAP-800℃/850℃solid solution-520℃aging,and800℃/850℃solid solution-ECAP-520℃aging)was *** experimental results show that the hot corrosion products of the six samples are similar,mainly Na_(2)Si_(2)O_(5),MoS_(2),TiCl_(2),Ti(SO_(4))_(2),and *** to the grains of the TB8 titanium alloy treated by 850℃solid solution-ECAP-520℃aging are obviously refined,the surface structure is the most smooth and dense,forming a continuous Al2O3protective film,and the surface defects are the least after *** corrosion layer thickness is the lowest(102.3μm),only 36.5%-81.4%of that of other secondary processing titanium *** addition,the corrosion kinetics curves of the six materials all follow parabolic laws,and the minimum corrosion weight gain of the samples after 850℃solutionECAP-520℃aging treatment is 0.7507 mg·mm^(-2),showing better hot corrosion resistance.

关键词： TB8 ECAP heat treatment hot corrosion resistance

Constitutive Relationship and Hot Processing Maps of Mg-Gd-Y-Nb-Zr Alloy

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Journal of Materials Science & Technology 2017年第7期33卷 637-644页

作者： Zhaohui Zhou Qichao Fan Zhihui Xia Aiguo Hao Wenhua Yang Wei Ji Haiqiao Cao institute of Machinery manufacturing Technology Chinese Academy of Engineering Physics Mianyang 621900 China

The hot working behavior of Mg-Gd-Y-Nb-Zr alloy was investigated using constitutive model and hot processing maps in this work. Isothermal compression tests were conducted with temperature and strain rate range of 703-773 K and 0.01-5 s^（-1）, respectively. Improved Arrhenius-type equation incorporated with strain compensations was used to predict flow behavior of the alloy, and the predictability was evaluated using correlation coefficient, root mean square error and absolute relative error. Processing maps were constructed at different strains for Mg-Gd-Y-Nb-Zr alloy based on dynamic materials *** processing maps are divided into three domains and the corresponding microstructure evolutions are referred to the forming of straight grain boundaries, twinning, dynamic recrystallization and grain growth. Instability occurred mainly at the strain rate range of 0.3s^（-1）-0.5s^（-1）. The optimum processing domain is mainly at the temperature range of 703-765 K with the strain rate range of 0.01-0.1 s^（-1）.

关键词： Magnesium alloy Recrystallization Constitutive model Processing maps Hot deformation

Mechanics analysis of axisymmetric thin-walled part in warm sheet hydroforming

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Chinese Journal of Aeronautics 2015年第5期28卷 1546-1554页

作者： Yang Xiying Lang Lihui Liu Kangning Liu Baosheng School of Mechanical Engineering and Automation Beihang University Beijing Aviation manufacturing Engineering institute

To obtain the influence of fluid pressure and temperature on warm hydroforming of 5A06-O aluminum alloy sheet, the unified mechanics equilibrium equations, which take through- thickness normal stress and friction into account, were established in spherical coordinate system. The distribution of through-thickness normal stress in the thickness direction was determined. The relation between through-thickness normal stress and fluid pressure was also analyzed in different regions of cylindrical cup. Based on the method of subtracting one increasing function from another, the constitutive equation of 5A06-O applied to warm hydroforming was established and in a good agreement with uniaxial tensile data. Based on whether the thickness variation was taken into account, two mechanic models were established to do the comparative study. The results for the studied case show that the calculated stress values are pretty close according to the two models and consistent with results of finite element analysis; the thickness distribution in flange computed by the second model conforms to the experimental data. Finally, the influences of fluid pressure on the flange thickness and radial stress were analyzed.

关键词： 5A06-O aluminum alloy:Constitutive equations:Fluid pressure:Through-thickness normalstress Warm sheet hydroforming

Active Learning Query Strategies for Classification,Regression,and Clustering:A Survey

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Journal of Computer Science & Technology 2020年第4期35卷 913-945页

作者： Punit Kumar Atul Gupta Indian institute of Information Technology Design and ManufacturingJabalpurMadhya Pradesh 482005India

Generally,data is available abundantly in unlabeled form,and its annotation requires some *** labeling,as well as learning cost,can be minimized by learning with the minimum labeled data *** learning(AL),learns from a few labeled data instances with the additional facility of querying the labels of instances from an expert annotator or *** active learner uses an instance selection strategy for selecting those critical query instances,which reduce the generalization error as fast as *** process results in a refined training dataset,which helps in minimizing the overall *** key to the success of AL is query strategies that select the candidate query instances and help the learner in learning a valid *** survey reviews AL query strategies for classification,regression,and clustering under the pool-based AL *** query strategies under classification are further divided into:informative-based,representative-based,informative-and representative-based,and ***,more advanced query strategies based on reinforcement learning and deep learning,along with query strategies under the realistic environment setting,are *** a rigorous mathematical analysis of AL strategies,this work presents a comparative analysis of these ***,implementation guide,applications,and challenges of AL are discussed.

关键词： active learning active learning query strategy active classification active regression active clustering deep active learning

MICRO-ROBOT FOR MEASUREMENT AND THREE-DIMENSION RECONSTRUCTION OF MICROPIPES

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Chinese Journal of Mechanical Engineering 2005年第3期18卷 371-375页

作者： Li Jiangxiong Ke Yinglin Guo Tong Wu Enqi Jin Chengzhu institute of manufacturing Engineering Zhejiang University Hangzhou 310027China

The presented system consists of field devices, a control system and a host computer system. The field devices, which are composed of an in-pipe micro-robot, a displacement sensor, a curvature sensor, and an inner surface measurement unit, can go into the pipe to get the data of displace- ment and axis curvature, and the shape data of the inner surface. With the conic-shape laser beam shot by the inner surface measurement unit, the intersectional curve between the laser beam and the inner-surface of the tested pipe can be calculated in the local coordination system （LCS） of the inner surface measurement unit. The relation between the LCS and the global coordination system （GCS） can be deduced, too. After the robot reaches the end of the pipe, all measured intersectional curves can be translated into the same coordination system to become a point cloud of the inner surface of the pipe according to the relations between LCS and GCS. Depending on this points cloud, the CAD model of the inner surface of the pipe can be reconstructed easily with reverse engineering tools, and the feature of flaw of the pipe can be obtained with flaw analysis tools.

关键词： 3D reconstruction Curved micro-pipe In-pipe micro-robot