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Microstructural Features and mechanical Behaviors of Al_(0.5)Cr_(0.8)CoFeNi_(2.5)V_(0.2) High-Entropy Alloys Fabricated by Selective Laser Melting Technique

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Acta Metallurgica Sinica(English Letters) 2022年第10期35卷 1591-1606页

作者： Yao Yan Wei-Dong Song Ke-Feng Li Kang Zhao Tong-Tong Sun Kai-Kai Song Jian-Hong Gong Li-Na Hu Shenzhen Research Institute of Shandong University Shenzhen518057China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China guangdong Institute of Materials and Processing Guangdong Academy of SciencesGuangdong UniversityGuangzhou510650China School of mechanical Electrical and Information EngineeringShandong UniversityWeihai264209China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan250061China

In this work,high strength and ductile Al_(0.5)Cr_(0.8)CoFeNi_(2.5)V_(0.2) high-entropy alloys(HEAs)were fabricated by the selective laser melting(SLM)*** orthogonal experiments,it was verified that a wide SLM processing parameter window can be used to produce crack-free samples for the investigated *** the printed HEA samples exhibit good densification higher than 98.3%.It was found that obvious epitaxial growth leads to the formation of the cylindrical and equiaxed ordered face-centered cubic(FCC)crystals,displaying the characteristics of sub-cylindrical and sub-cellular *** low-angle grain boundaries(LAGBs)prefer appearing around subgrain structures,while the high-angle grain boundaries(HAGBs)tend to form around coarse *** HEA samples with high and low apparent densities were selected to observe their mechanical properties,which exhibit Vickers hardness higher than 263 HV and do not fail during *** increasing densification,the strength gradually *** to the engineering stress–strain curves during compression,the yield strength is higher than 530 MPa,while the strength near 40%engineering strain is larger than 1840 *** deformation,a large density of dislocations becomes popular within subgrain structures together with the pre-existing dislocations from rapid solidification,leading to the formation of planar and cross slip *** coarse cylindrical crystals,some deformation twins are also induced together with the appearance of a distinct copper-type texture during *** a result,the as-printed samples display better mechanical properties than the as-cast *** present studies provide a very good HEA candidate for the SLM process,but more work should be conducted to achieve excellent comprehensive properties.

关键词： High-entropy alloys Selective laser melting mechanical properties Microstructures

Design and Implementation of a Communication Network and Operating System for an Adaptive Integrated Hybrid AC/DC Microgrid Module

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CSEE Journal of Power and Energy Systems 2018年第1期4卷 19-28页

作者： Xuewei Pan Longqi Zhang Jianfang Xiao Akshay K.Rathore Peng Wang School of mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen)ShenzhenGuangdong518055China School of electrical and Computer Engineering Nanyang Technological University639798Singapore Department of electrical and Computer Engineering Concordia UniversityMontrealQC1455Canada

This paper proposes an adaptive integrated hybrid AC/DC microgrid module to accommodate a wide range of distributed renewable energy resources(DRERs),distributed energy storage devices(DESDs)and distributed demand resources(DDRs)into the existing distribution *** microgrid module is designed to be portable,scalable,easy to deploy,and simple to *** modeling of the proposed microgrid module,based on the IEC 61850 standard,is presented.A novel logical node is introduced,which describes functionalities of the bidirectional interlinking converter(BIC)interfacing AC sub-grid and DC sub-grid in a better *** achieve the target of plug-and-play functionalities,specific microgrid module communication network(MMCN)and microgrid module operating systems(MMOS)are designed and implemented in the hardware prototype built in the *** results obtained from the lab prototype clearly validate the effectiveness of the proposed design of the microgrid module,communication network and operating system.

关键词： AC/DC Adaptive communication network hybrid IEC61850 integrated microgrid operating system

Electrochemical micromachining of micro-dimple arrays on cylindrical inner surfaces using a dry-film photoresist

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Chinese Journal of Aeronautics 2014年第4期27卷 1030-1036页

作者： Qu Ningsong Chen Xiaolei Li Hansong Zeng Yongbin College of mechanical and electrical Engineering Nanjing University of Aeronautics and Astronautics Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology

The application of surface textures has been employed to improve the tribological performance of various mechanical components. Various techniques have been used for the application of surface textures such as micro-dimple arrays, but the fabrication of such arrays on cylindrical inner surfaces remains a challenge. In this study, a dry-film photoresist is used as a mask during through-mask electrochemical micromachining to successfully prepare micro-dimple arrays with dimples 94 lm in diameter and 22.7 lm deep on cylindrical inner surfaces, with a machining time of 9 s and an applied voltage of 8 V. The versatility of this method is demonstrated, as are its potential low cost and high efficiency. It is also shown that for a fixed dimple depth, a smaller dimple diameter can be obtained using a combination of lower current density and longer machining time in a passivating sodium nitrate electrolyte.

关键词： Dry-film photoresist Electrochemical machining Electrochemical micromachining Inner surface Micro-dimple arrays Texture

Study on sensitivity of Nb to high-temperature ductility dip crack of inconel 690

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China Welding 2020年第4期29卷 54-59页

作者： Wang Jixiao Wang Li Wang Jun Jin Guo School of mechanical and electrical Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China National University Science Park Harbin Engineering UniversityHarbin 150001China

Sensitivity of Nb to high-temperature ductility dip crack(HTDDC) of deposited metal of Inconel 690 welding wire was studied in detail. Strain to fracture test and high-temperature tensile test were selected as the test methods to study the sensitivity of HTDDC. The deposited metals of four kinds of welding wire were observed and analyzed by OM and SEM. Experiment results show that Nb can effectively improve the ability of Inconel 690 to resist HTDDC and reduce the crack sensitivity of deposited metal. The mechanism of HTDDC is the grain boundary strength of deposited metal is lower than the intragranular strength. The(Nb, Ti) C can effectively block the grain boundary sliding and improve the resistance to deformation of the grain boundary.

关键词： Inconel690 crack welding wire deposited metal sensitivity

Numerical simulation for sheet metal forming process of 16Mn blade of large concrete-mixer truck

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Journal of Central South University of Technology 2005年第1期12卷 83-87页

作者：王锦红夏伟周照耀陈维平郧建国 College of mechanical Engineering South China University of Technology Guangzhou 510640 China Department of mechanical and electrical Engineering Shaoguan University Shaoguan 512005 China

A finite element analysis method was used to simulate the stamping process of the blade of a large concrete-mixer truck. The updated Lagrange method and the elasto-plastic constitutive equation were adopted to solve the large strain and displacement deformation of the blade. A modified Coulomb friction model was used to solve the sliding contact between the blade and the dies. The von Mises stress distribution in the blade, the spatial displacement variation and the spring-back of the typical node were investigated in the simulation. The von Mises stress in the blade where the spring-back occurs is lowered from 463.0MPa to 150.0MPa before and after the spring-back. A typical node in the blade has a 3.33mm spring-back in Z direction. The results of the (experiments) agree well with the simulation. The analysis results are valuable for designing optimal tool dies.

关键词： finite element simulation spring-back stamping process concrete-mixer truck blade

Development of accumulative roll bonding for metallic composite material preparation and mechanical/functional applications

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Journal of Iron and Steel Research International 2024年第11期31卷 2611-2621页

作者： Bo Feng Hao-kun Yang Xiao-hui Li Xiao-wei Feng Tian-lai Chen Guo-feng Li guangdong Provincial Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510000GuangdongChina Smart Manufacturing Division Hong Kong Productivity CouncilHong Kong 999077China School of Mechatronic Engineering and Automation Foshan UniversityFoshan 510168GuangdongChina Foshan Tongbao electrical Precision Alloy Co. Ltd.Foshan 510168GuangdongChina

Accumulative roll bonding(ARB)is a severe plastic deformation method to prepare the metallic composite material by physical method at room to elevate temperature,without the generation of additional waste solid or *** the physical characteristicsmulti-material and hybrid structure,the mechanical and function properties of the ARB composite material,like Al/steel,Al/Mg,Al/Cu,etc.,shall have the"1+1>2"effect on the mechanical and functional properties,including the remarkable properties that include lightweight,high strength,thermal/electrical conductivity,electromagnetic shielding,and other *** deeply investigate the preparation method and microstructural evolution of various metal laminates by ARB,as well as the mechanical and functional properties of the laminate,an overview of the history of ARB technique,the breakthrough of ARB sheet properties,as well as the relative products in industries is ***-tionally,the future development of ARB technology and the utilization of composite materials in different areas will be discussed.

关键词： Accumulative roll bonding Metal-Composite material:mechanical property Functional property:Industrial application

Fault Analysis of Wind Power Rolling Bearing Based on EMD Feature Extraction

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Computer Modeling in Engineering & Sciences 2022年第1期130卷 543-558页

作者： Debiao Meng Hongtao Wang Shiyuan Yang Zhiyuan Lv Zhengguo Hu Zihao Wang School of mechanical and electrical Engineering University of Electronic Science and Technology of ChinaChengdu611731China Institute of Electronic and Information Engineering of UESTC in guangdong Dongguan523808China Yangzhou Yangjie Electronic Technology Co. Ltd.Yangzhou225008China

In a wind turbine,the rolling bearing is the critical ***,it has a high failure ***,the failure analysis and fault diagnosis of wind power rolling bearings are very important to ensure the high reliability and safety of wind power *** this study,the failure form and the corresponding reason for the failure are discussed ***,the natural frequency and the characteristic frequency are *** Empirical Mode Decomposition(EMD)algorithm is used to extract the characteristics of the vibration signal of the rolling ***,the eigenmode function is obtained and then filtered by the kurtosis ***,the relationship between the actual fault frequency spectrum and the theoretical fault frequency can be *** the fault analysis is *** enhance the accuracy of fault diagnosis,based on the previous feature extraction and the time-frequency domain feature extraction of the data after EMD decomposition processing,four different classifiers are added to diagnose and classify the fault status of rolling bearings and compare them with four different classifiers.

关键词： Wind turbine rolling bearing fault diagnosis empirical mode decomposition

Saddlepoint Approximation Method in Reliability Analysis:A Review

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2329-2359页

作者： Debiao Meng Yipeng Guo Yihe Xu Shiyuan Yang Yongqiang Guo Lidong Pan Xinkai Guo School ofmechanical and electrical Engineering University of Electronic Science and Technology of ChinaChengdu611731China Institute of Electronic and Information Engineering of UESTC in guangdong Dongguan523808China Glasgow College University of Electronic Science and Technology of ChinaChengdu611731China Beijing Research Institute of mechanical&electrical Technology Ltd.Beijing100083China

The escalating need for reliability analysis(RA)and reliability-based design optimization(RBDO)within engineering challenges has prompted the advancement of saddlepoint approximationmethods(SAM)tailored for such *** article offers a detailed overview of the general SAM and summarizes the method characteristics ***,recent enhancements in the SAM theoretical framework are ***,the mean value first-order saddlepoint approximation(MVFOSA)bears resemblance to the conceptual framework of the mean value second-order saddlepoint approximation(MVSOSA);the latter serves as an auxiliary approach to the *** distinction is rooted in the varying expansion orders of the performance function as implemented through the Taylor *** the saddlepoint approximation and third-moment(SATM)and saddlepoint approximation and fourth-moment(SAFM)strategies model the cumulant generating function(CGF)by leveraging the initial random moments of the *** their optimal application domains diverge,each method consistently ensures superior relative precision,enhanced efficiency,and sustained *** method elucidated is exemplified through pertinent RA or RBDO *** juxtaposing them against alternative strategies,the efficacy of these methods becomes *** outcomes proffered are subsequently employed as a foundation for contemplating prospective theoretical and practical research endeavors concerning *** main purpose and value of this article is to review the SAM and reliability-related issues,which can provide some reference and inspiration for future research scholars in this field.

关键词： Reliability analysis reliability-based design optimization saddlepoint approximation

Robust identification of weld seam based on region of interest operation

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Advances in Manufacturing 2020年第4期8卷 473-485页

作者： Ying-Zhong Tian Hong-Fei Liu Long Li Wen-Bin Wang Jie-Cai Feng Feng-Feng Xi Guang-Jie Yuan School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444People's Republic of China School of mechanical and electrical Shenzhen PolytechnicShenzhen 518055GuangdongPeople's Republic of China Shanghai Rui Rong Laser Welding Technology Co. LtdShanghai 201306People's Republic of China Department of mechanical Aerospace and Industrial EngineeringRyerson UniversityTorontoCanada

For welding path determination,the use of vision sensors is more effctive compared with complex ofline programming and teaching in small to medium volume ***,interference factors such as scratches and stains on the surface of the workpiece may affect the extraction of weld *** the obtained weld image,the weld seams have two distinct features related to the workpiece,which are continuous in a single process and separated from the workpiece's gray *** this paper,a novel method is proposed to identify the welding path based on the region of interest(ROI)opera-tion,which is concentrated around the weld seam to reduce the interference of external *** complete the identi-fication of the entire welding path,a novel algorithm is used to adaptively generate a dynamic ROI(DROI)and perform iterative *** identification accuracy of this algorithm is improved by setting the boundary condi-tions within the ***,the experimental results confirm that the coefficient factor used for determining the ROI size is a pivotal influencing factor for the robustness of the algorithm and for obtaining an optimal *** this algorithm,the welding path identification accuracy is within 2 pixels for three common butt weld types.

关键词： Passive vision Noise reduction Welding path identification Region of interest(ROI)