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Surface quality of extruding metal special-shape products and frictional behavior in optimized die cavity

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 468-471页

作者： QI Hong-yuan ZHU heng-jun School of Mechanical and Electric Control Engineering Beijing Jiaotong University Beijing 100044 China School of Mechanical and Electric Control Engineering Beijing Jiaotong University Beijing 100044 China

With the help of Complex Function Mapping theory, the complicated three-dimensional deformation problems are transferred into two-dimensional problems, and the function of strain ratio field is analyzed in the metal plastic extruding deformation. Taking the strain-hardening effect of metal deformation into account, the relationship between friction behavior and optimized mathematical model is analyzed by the numerical analysis friction energy dissipation function. As a result, the method of lowering the material hardening and decreasing the reduction ratio over multi-procedures can be used to improve the surface quality of metal special-shape extrusion products.

关键词： special-shape products extrusion surface quality Conformal Mapping

Active Damping of Milling Vibration Using Operational Amplifier Circuit

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 58-65页

作者： Bashir Bala Muhammad Min Wan Yang Liu heng yuan School of Mechanical Engineering Northwestern Polytechnical University

The problem of chatter vibration is associated with adverse consequences that often lead to tool impairment and poor surface finished in a workpiece, and thus, controlling or suppressing chatter vibrations is of great significance to improve machining quality. In this paper, a workpiece and an actuator dynamics are considered in modeling and controller design. A proportional-integral controller(PI) is presented to control and actively damp the chatter vibration of a workpiece in the milling process. The controller is chosen on the basis of its highly stable output and a smaller amount of steady-state error. The controller is realized using analog operational amplifier circuit. The work has contributed to planning a novel approach that addresses the problem of chatter vibration in spite of technical hitches in modeling and controller design. The method can also lead to considerable reduction in vibrations and can be beneficial in industries in term of cost reduction and energy saving. The application of this method is verified using active damping device actuator(ADD) in the milling of steel.

关键词： Active damping Anti-windup Bending moment Milling process Workpiece vibration Operational amplifier Proportional integral controller

Determination of optimal geometrical parameters of peripheral mills to achieve good process stability

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Advances in Manufacturing 2018年第3期6卷 259-271页

作者： Min Wan heng yuan Ying-Chao Ma Wei-Hong Zhang School of Mechanical Engineering Northwestern Polytechnical University Xi'an 710072 Shaanxi People'sRepublic of China State IJR Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi'an 710072 Shaanxi People's Republic of China

This paper focuses on optimization of the geo-metrical parameters of peripheral milling tools by takinginto account the dynamic effect. A substructure synthesistechnique is used to calculate the frequency responsefunction of the tool point, which is adopted to determinethe stability lobe diagram. Based on the Taguchi designmethod, simulations are first conducted for varying com-binations of tool overhang length, helix angle, and teethnumber. The optimal geometrical parameters of the tool aredetermined through an orthogonal analysis of the maxi-mum axial depth of cut, which is obtained from the pre-dicted stability lobe diagram. It was found that thesequence of every factor used to determine the optimal toolgeometrical parameters was the tool overhang length, teethnumber, and helix angle. Finally, a series of experimentswere carried out as a parameter study to determine theinfluence of the tool overhang length, helix angle, and teethnumber on the cutting stability of a mill. The same con-clusion as that obtained through the simulation wasobserved.

关键词： Substructure synthesis technique Frequencyresponse function Tool geometrical parameter Taguchidesign method

Recent Advances in C_(2) Gases Separation and Purification by Metal-Organic Frameworks

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Chinese Journal of Structural Chemistry 2022年第11期41卷 31-44页

作者： Zhengyi Di Xinjing Zheng Yu Qi heng yuan Cheng-Peng Li College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002.China

Separation of C_(2) gases(C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2))mixtures is one of the most important and energy-demanding processes in chemical *** separation methods(fine distillation separation and selective catalytic hydrogenation separation)have the shortages of high energy consumption and inefficient use of resources,affecting the achievement of peak carbon dioxide emissions and carbon neutrality *** based on adsorption is considered as one of the best ways to achieve low-energy ***,it is of great importance to synthesize materials that enable the effective separation and purification of C_(2) gases under mild *** an emerging class of porous materials,metal-organic frameworks(MOFs)show great promise in the field of gas separation and purification due to their ultra-high specific surface area,easily modifiable pore surfaces,structural designability and ***,we summarize recent research advances by use of MOFs sorbents for the separation and purification of C_(2) gases,including C_(2)H_(2)/C_(2)H_(4),C_(2)H_(6)/C_(2)H_(4) and C_(2)H_(2)/CO_(2).Relationship between structures and separation mechanism is also ***,challenges and possible research directions related to the further exploration are also discussed.

关键词： MOFs adsorption and separation C_(2)gas design and synthesis pore size

Theoretical and numerical research on effect of tension mechanisms in strip flatness electromagnetic control rolling mills

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Journal of Iron and Steel Research International 2024年第9期31卷 2217-2235页

作者： Ting-song Yang Tie-heng yuan Wen-quan Sun An-rui He Chun-tao Qu National Engineering Research Center of Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing100083China Institute of Aeronautical Power Machinery AECC Harbin Dongan Engine Co.Ltd.Harbin150000HeilongjiangChina

To achieve stable rolling,the influence of a tension mechanism of a large diameter ratio roll system on the rolling process of a strip flatness electromagnetic control rolling mill is *** the analysis of the rolling deformation zone,the deformation zone composition form of a large diameter ratio roll system and a calculation formula of neutral angle under tension are *** analyze the effect of front and post tensions on the rolling characteristic and the strip flatness control characteristic,a three-dimensional rolling finite element(FE)model of a large diameter ratio roll system with the function of roll profile electromagnetic control is established by FE software and verified by a strip flatness electromagnetic control rolling *** on the model,the strip thickness characteristic,metal transverse flow,strip flatness state,and adjustment range of the loaded roll gap are analyzed for different front and post tensions setting *** results show that changing the front or post tension setting values can improve the single-pass reduction rate of a large diameter ratio roll system and have little effect on the flatness control ability of the strip flatness electromagnetic control rolling mill.

关键词： Strip flatness electromagnetic control rolling mill Tension mechanism Roll profile electromagnetic control technology Rolling characteristic Strip flatness control characteristic

Covalent Organic Frameworks(COFs) for Sequestration of ^(99)TcO_(4)^(–)

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Chemical Research in Chinese Universities 2022年第2期38卷 290-295页

作者： DI Zhengyi MAO Yining yuan heng ZHOU Yan JIN Jun LI Cheng-Peng College of Chemistry Tianjin Key Laboratory of Structure and Performance for Functional MoleculesTianjin Normal UniversityTianjin 300387P.R.China

Covalent organic frameworks(COFs),as a class of crystalline porous materials with periodic lattices and porous structures,have received extensive attention in the fields of gas storage and separation,energy storage,catalysis and optoelectronics and so ***,COFs are still in their infancy in the field of nuclear waste treatment,especially for sequestration of long-live problematic radionuclides,such as *** of decontamination of pertechnetate(TcO4–),a main existence of 99Tc under aerobic environments,is far from *** this review,recent progresses of COFs and some relative materials in the sequestration of pertechnetate,and perspective on surmounting the unmet issues are elucidated.

关键词： Covalent organic framework(COF) Radionuclide sequestration 99TcO4– Adsorption Anion exchange

Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

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Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin Liu Ming-Fu Lyu heng-yuan Zhang Jian-Ye Liu Shi-Jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology

Microemulsion leaching of vanadium from sodium-roasted vanadium slag by fusion of leaching and extraction processes

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 974-980页

作者： Yun Guo Hong-yi Li Yi-heng yuan Jie Huang Jiang Diao Gang Li Bing Xie College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

The fusion of the leaching and purification processes was realized by directly using microemulsion as the leaching *** bis-(2-ethyhexyl)phosphoric acid(DEHPA)/n-heptane/NaOH microemulsion system was established to directly leach vanadates from sodium-roasted vanadium *** effect of the leaching agent on the leaching efficiency was investigated,in addition to the molar ratio of H_(2)O/NaDEHP(W),DEHPA concentration,solid/liquid ratio,stirring time,and leaching *** optimal situations,the vanadium leaching efficiency reaches 79.57%.The X-ray diffraction characterization of the leaching residue and the Raman spectrum of the microemulsion before and after leaching demonstrate the successful entry of vanadates from the sodium-roasted vanadium slag into the *** proposed method successfully realizes the leaching and purification of vanadates in one step,thereby greatly reducing production costs and environmental *** also offers a new way to achieve the green recovery of valuable metals from solid resources.

关键词： vanadium slag sodium roasting clinker microemulsion leaching extraction

Effect of post rolling stress on phase transformation behavior of microalloyed dual phase steel

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Journal of Iron and Steel Research International 2024年第3期31卷 688-699页

作者： Wen-quan Sun Sheng-yi Yong Tie-heng yuan Ting-song Yang An-rui He Chao Liu Rui-chun Guo National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China

The slow phase transformation of microalloyed dual phase steel makes the nonuniform stress and temperature fields during the post rolling cooling process have a significant impact on the phase transformation *** the relatively slow phase transformation of DP780 steel within the microalloyed dual phase steel series,the influence of stress on the phase transformation behavior of DP780 steel was *** quantify the nonuniform thermal and stress conditions in the steel coil,a thermo-mechanical coupled finite element model of the hot-rolled strip cooling process was *** on the simulation data,DP780 steel was chosen as the research material,and Gleeble 3500 thermal simulation equipment was used for experimental *** thermal expansion curves were analyzed through regression to establish the dynamic model of DP780 steel phase transformation under ***,metallographic analysis was conducted to determine phase transformation type and grain size of DP780 *** results confirmed that the stress promotes the occurrence of semi-diffusion-type bainite ***,an appropriate level of stress facilitates the growth of bainitic grains,while the increased stress inhibits the growth of ferritic grains.

关键词： Microalloyed dual phase steel Stress Bainitic transformation Grain Finite element method