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Radial envelope forming mechanism and process design method for cylindrical rings with thin wall and high web ribs

Chinese Journal of Aeronautics 2023年第12期36卷 461-476页

作者： Xinghui HAN Yanlei MIN Wuhao ZHUANG Lin HUA Duanyang TIAN Zushen DENG Ningbo LIU Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong LaboratoryXiangyang 441000China

Cylindrical rings with thin wall and high web ribs(CRTWHWR)are widely used as the key load bearing structures such as rocket body and space station cabin in aerospace ***,it is still difficult to efficiently manufacture CRTWHWR with high performance because of their extreme geometry with thin-walled skins,high web ribs and large *** this paper,a novel radial envelope forming process is put forward to efficiently achieve the plastic forming of CRTWHWR with high ***,the principle of radial envelope forming process is ***,an efficient design method for the tool motion and geometry is proposed based on the reverse envelope principle,i.e.,CRTWHWR is adopted to reversely envelope the tool and thus the tool which does not interfere with CRTWHWR can be efficiently obtained in a single ***,a reasonable 3D FE model of the radial envelope forming process of CRTWHWR is established and the radial envelope forming mechanism of CRTWHWR is comprehensively *** the FE simulation and experiments with material of plastic mud,a typical CRTWHWR with diameter of 300 mm,axial height of 192 mm,the maximum rib height of 25 mm,the minimum rib thickness of 3 mm and skin thickness of 5 mm is radial envelope formed,i.e.,the ratio of the maximum rib height to the minimum rib thickness reaches 8.33,the ratio of the maximum rib height to skin thickness reaches 5 and the ratio of diameter to the minimum rib thickness reaches *** above results verify that the proposed radial envelope forming process has great potentials in efficiently manufacturing CRTWHWR with extreme geometry.

关键词： Radial envelope forming Cylindrical ring with thin wall and high web ribs forming mechanism FE simulation Tool design

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Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1322-1332页

作者： Qinghe Cui Xuefeng Liu Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik Jr. Dzmitry Bahrets Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Technical Acoustics National Academy of SciencesVitebsk 210009Belarus

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the *** technology has a very broad application prospect in industrial *** have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this *** this review,metals were classified according to their crystal *** effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were *** main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

关键词： ultrasonic vibration plastic forming crystal structure microstructure forming mechanism

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Research on the forming mechanism of Micro/Nano Features during the Cast Molding Process

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Nano-Micro Letters 2011年第4期3卷 249-255页

作者： Xiangdong Ye Yugang Duan Yucheng Ding Key Laboratory of Photonic and Electronic Materials School of Electronic Science and EngineeringNanjing University State Key Laboratory of Manufacturing Systems Engineering Xi’an Jiaotong University

Cast molding process has provided a reliable, simple and cost-effective way to fabricate micro structures since decades ago. In order to obtain structures with fine, dense and deep nano-size features by cast molding, it is necessary to study the forming mechanism in the process. In this paper, based on major steps of cast molding, filling models of liquid are established and solved; and the forming mechanism of liquid is revealed. Moreover, the scale effect between the liquid and the cavity on the filling velocity of liquid is *** is also interesting to find out that the wettability of liquid on the cavity may be changed from wetting to dewetting depends on the pressure difference. Finally, we experimentally verify some of our modeling results on the flowing and filling state of the liquid during the cast molding process.

关键词： forming mechanism Cast molding process Nano-size features Liquid

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Structure, Antibacterial Activity and Theoretical Study of the forming mechanism of Compound [(5-Methyl-3-oxo-2-phenyl-1H-pyrazol-4-yl)-thiophen-2-yl-methylene] Thiosemicarbazide

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Chinese Journal of Structural Chemistry 2014年第9期33卷 1275-1280页

作者：朱华玲朱金花黄治强吕丽娟尉震 Department of Basic Science Tianjin Agricultural College Meteorological Service Center of Shanxi Province

A new thiosemicarbazone compound derived from 1-phenyl-3-methyl-4-（2-thenoyl） pyrazolone-5 （HPMTP） and thiosemicarbazide has been synthesized and characterized by IR, H- NMR, MS, elemental analysis, UV and single-crystal X-ray diffraction. The compound crystallizes in monoclinic system, Cc space group with a = 7.5925（8）, b = 20.263（2）, c = 11.4669（13） A, r= 107.825（8）°, V = 1679.5（3） A3, Z = 4, R = 0.0316 and wR = 0.0687. The results of antibacterial activity test against Escherichia coli and Bacillus subtilis indicate that the compound possesses the same antibacterial activity as the contrast （Norfloxacin）. Theoretical study of the forming mechanism to the title compound at the RHF/6-31G（d） level shows that there are two steps. The distal amino group of thiosemicarbazide is added to the 4-carbonyl group of HPMTP which forms TM. Then a dehydration reaction occurs in TM and generates a stable product PC.

关键词： synthesis structure antibacterial activity forming mechanism

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forming and uniformity of shaft parts without a stub bar by axial closed-open-type cross-wedge rolling

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Journal of Iron and Steel Research International 2020年第9期27卷 1054-1063页

作者： Xue-dao Shu Song Zhang Kornel F.Ehmann Zi-xuan Li Yi-lun Wei College of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211ZhejiangChina 2 College of Mechanical EngineeringNorthwestern UniversityEvanston 60208IllinoisUSA

To realize cross-wedge rolling of shaft parts without a stub bar in a short process,an axial closed-open-type cross-wedge rolling technique was *** on the strain characteristics in the rolling,evaluation indices of deformation uniformity were provided,and the DEFORM-3D software was adopted to conduct numerical simulations of the rolling *** metal flow and strain distribution in all stages of the rolling process were *** is shown that the strain value of the rolled piece close to the end is relatively high while the overall strain distribution is uniform in the rolling *** the percentage reduction in area is smaller,the fluctuation range of the equivalent strain will be lower and the overall uniformity of the rolled piece will be better.A variable angle wedge was implemented to make metal flow inward and eliminate ***,rolling experiment was performed,which indicate that the shape of the rolled piece obtained is consistent with the simulation *** value in the rolling is decreased by 92%as compared to conventional open *** research results lay a theoretical basis for realizing closed-open-type cross-wedge rolling without a stub bar.

关键词： Closed–open-type rolling Cross-wedge rolling Stub bar forming mechanism Uniformity

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Micro Electrical Discharge Machining Deposition in Air for Fabrication of Micro Spiral Structures

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Chinese Journal of Mechanical Engineering 2010年第2期23卷 154-160页

作者： PENG Zilong CHI Guanxin WANG Zhenlong Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of Technology Harbin 150001 China School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

Micro electrical discharge machining（EDM） deposition process is a new micro machining method for fabrication of metal micro structures. In this process, the high level of tool electrode wear is used to achieve the metal material deposition. Up to now, the studies of micro EDM deposition process focused mainly on the researches of deposition process, namely the effects of discharge parameters in deposition process on the deposition rate or deposition quality. The research of the formation of micro structures with different discharge energy density still lacks. With proper conditions and only by the z-axis feeding in vertical direction, a novel shape of micro spiral structure can be deposited, with 0.11 mm in wire diameter, 0.20 mm in outside diameter, and 3.78 mm in height. Then some new deposition strategies including angular deposition and against the gravity deposition were also successful. In order to find the forming mechanism of the spiral structures, the numerical simulation of the transient temperature distribution on the discharge point was conducted by using the finite-element method（FEM）. The results show that there are two major factors lead to the forming of the spiral structures. One is the different material removal form of tool electrode according with the discharge energy density, the other is the influenced degree of the movement of the removed material particles in the discharge gap. The more the energy density in single discharge is, the smaller the mass of the removed material particles is, and the easier the movements of which will be changed to form an order tendency. The fine texture characteristics of the deposited micro spiral structures were analyzed by the energy spectrum analysis and the metallographic analysis. It shows that the components of the deposited material are almost the same as those of the tool electrode. Moreover the deposited material has the brass metallic luster in the longitudinal profile and has compact bonding with the

关键词： micro electrical discharge machining deposition micro spiral structure forming mechanism fine texture analysis

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Formation mechanisms and Geomorphic Evolution of the Erlian Mudflow Fans, Eastern Guide Basin of the Upper Reaches of Yellow River

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Acta Geologica Sinica(English Edition) 2016年第2期90卷 578-589页

作者： ZHAO Wuji YIN Zhiqiang XU Qiang QIN Xiaoguang School of the Earth Sciences and Resources China University of Geosciences Beijing 100083 China China Institute of Geo-environment Monitoring Beijing 100081 China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China

Several argillaceous platforms lie along the Yellow River（YR） of the eastern Guide Basin, northeastern Tibetan Plateau, and their compositions, formation processes, and geomorphic evolution remain debated. Using field survey data, sample testing, and high-resolution remote sensing images, the evolution of the Erlian mudflow fans are analyzed. The data show significant differences between fans on either side of the YR. On the right bank, fans are dilute debris flows consisting of sand and gravel. On the left bank, fans are viscosity mudflows consisting of red clay. The composition and formation processes of the left bank platforms indicate a rainfall-induced pluvial landscape. Fan evolution can be divided into two stages： early-stage fans pre-date 16 ka B.P., and formed during the last deglaciation; late-stage fans post-date 8 ka B.P.. Both stages were induced by climate change. The data indicate that during the Last Glacial Maximum, the northeastern Tibetan Plateau experienced a cold and humid climate characterized by high rainfall. From 16–8 ka, the YR cut through the Erlian early mudflow fan, resulting in extensive erosion. Since 8 ka, the river channel has migrated south by at least 1.25 km, and late stage mudflow fan formation has occurred.

关键词： the upper reaches of Yellow River Guide Basin mud-flow fan forming mechanism geomorphic evolution

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Formation mechanism of High Quality Marine Source Rocks-Coupled Control mechanism of Geological Environment and Organism Evolution

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Journal of Earth Science 2011年第3期22卷 326-339页

作者：腾格尔胡凯孟庆强黄娟付小东谢小敏仰云峰高长林 Wuxi Research Institute of Petroleum Geology SINOPEC Department of Earth Sciences Nanjing University

High quality marine source rock （HQMSR） is the key prerequisite for medium to large hydrocarbon accumulations. However, the forming mechanism remains unclear. On the basis of the in-vestigation for the geodynamic setting of the Middle-Upper Yangtze during the Early Cambrian in dif-ferent spatial scales and the analysis of trace elements, the main controlling factors of the development of high quality marine source rock are discussed, with specific consideration of the burial rate of the organic matter. The formation of high quality marine source rocks is suggested to be the result of a co-ordinated development and the interaction between geological environments and organism evolution during the major geological transition periods. We perceived that the burial rate of organic matter was influenced by the primary productivity and its burial conditions. The abundance of autogenetic molyb-denum gained directly by the chemical speciation analysis of rocks could be used as a proxy for the burial organic matter. The burial rate of autogenetic molybdenum and the sedimentary organics in modern marine environments could be used to estimate the sedimentary organics in ancient environ-ments effectively.

关键词： high quality marine source rock forming mechanism geodynamics geological envi-ronment organic evolution speciation analysis.

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企业非市场策略与国际贸易摩擦的形成及化解

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外贸经济、国际贸易 2007年第6期 65-76页

作者：李春顶

国际贸易摩擦相关文献较多的从国家和政府的角度来研究摩擦的成因、效应和应对策略，而从企业行为的层面来分析贸易摩擦问题则是一个更加直接和全新的视角。同时，在国际贸易摩擦的形成机制探索中，纯粹的经济学假设条件似乎难以给出富... 详细信息

国际贸易摩擦相关文献较多的从国家和政府的角度来研究摩擦的成因、效应和应对策略，而从企业行为的层面来分析贸易摩擦问题则是一个更加直接和全新的视角。同时，在国际贸易摩擦的形成机制探索中，纯粹的经济学假设条件似乎难以给出富有说服力的解释，于是更多的研究转向了政治行为，文章则是从政治背后的根源——也就是企业竞争行为中的非市场策略入手。以双头的竞争模型研究了国际贸易摩擦的形成机制，并从中引出了化解摩擦的路径以及可行性条件。

关键词：非市场策略国际贸易摩擦形成机制化解路径 nonmarket strategy international trade friction forming mechanism resolving path

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Studies on α-Methacrylate Copper(Ⅱ)Com plexes with Im idazole

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Chemical Research in Chinese Universities 1999年第3期15卷 243-247页

作者： WANG Yao-yu SHI Qian SHI Qi-zhen GAO Yi-ci ZHOU Zhong-yuan Department of Chemistry Northwest UniversityXi'an 710069P.R.China Department of Chemistry Lanzhou UniversityLanzhou 730000P.R.China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041P.R.China

Two complexes of α methacrylate copper(Ⅱ) with imidazole, Cu[CH 2C(CH 3)COO] 2· (imH) 2(1) and Cu 2[CH 2C(CH 3)COO] 4(imH) 2(2) were prepared and characterized. The single crystal X ray diffraction study of complex 1 showed that the copper(Ⅱ) atom in the symmetric centre of the square planar environment was coordinated by two monodentate α methacrylate groups and two imidazole ligands that were in trans position with each other. Each molecular unit is linked with four neighbouring units by means of hydrogen bond interactions, forming a two dimensional supermolecular compound( d N…O =0 278 1 nm). Complex 1 crystallizes in monoclinic, space group P2 1/n with a =1 023 94(12) nm, b =0 842 94(8) nm, c =1 079 35(10) nm, β=117 231(7)°, Z =2. The forming mechanism of the complexes was discussed.

关键词： Copper(Ⅱ)T-methacrylate Imidazole Crystal structure forming mechanism

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