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SSRN 2024年

作者： Zheng, Yihang Hou, Tingping Cheng, Shi Yang, Yuhao Zhang, Dong Zeng, Wenfeng Xiong, Wu Wu, Kaiming The State Key Laboratory of Refractories and Metallurgy Joint International Research Laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical Processing International Research Institute for Steel Technology Collaborative Center on Advanced Steels Wuhan University of Science and Technology Wuhan430081 China Wuhan Heavy Industry Casting and Forging Co. Ltd Wuhan430081 China

The physical mechanism of the magnetic field-induced phase transition for M23C6/α-Fe was investigated utilizing a combination of high-resolution transmission electron microscopy (HRTEM) with Micromagnetic theory. The HRTEM results revealed that the M23C6/α-Fe interface exhibited a specific magnetic field-induced phase transition under the action of a high-temperature magnetic field, which increased the interface thickness between the carbide and matrix. Micromagnetic modeling establishes the relationship between the boundary thickness and the external magnetic field. The magnetization curves of carbide and matrix under high magnetic field are significantly shifted toward high temperature, which contributes to the reduction of the magnetic structure difference between M23C6 and α-Fe. The application of a strong magnetic field has a notable effect on the magnetization curve, shifting it towards higher temperatures. This diminishes the discrepancy in magnetic structure between M23C6 and α-Fe, leading to a substantial reduction in magnetostatic energy while concurrently augmenting magnetic exchange energy. Consequently, this process results in an increased thickness of the boundary between M23C6 and α-Fe. Combination of experiment and theory verifies the physical mechanism of the phase transition of carbides by magnetic field to provide a new theoretical basis for the formation of carbides by magnetic field. © 2024, The Authors. All rights reserved.

关键词： Carbides

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Mobility analysis of a deployable truss-antenna mechanism-Method based on link-demolishing and equivalent idea

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Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica 2017年第9期38卷 421188-1-421188-1-421188-12页

作者： Xu, Yundou Liu, Wenlan Chen, Liangliang Yao, Jiantao Zhao, Yongsheng Zhu, Jialong Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao066004 China Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University Qinhuangdao066004 China Xi'an710100 China

A method for Degree Of Freedom (DOF) analysis of spatial mechanisms with multiple coupled-loops is proposed based on the link-demolishing and equivalent idea, in view of the multi-loop coupling characteristic of a deployable truss antenna assembled by tetrahedral elements. The coupling constraint chain of the deployable tetrahedral element is removed, and the remainder is regarded as a parallel mechanism. The number and characteristic of the DOF of each output node are then analyzed using the screw theory, and the equivalent serial kinematic chain between the output nodes and the fixed node are then established. The equivalent mechanism of the deployable tetrahedral element is obtained by reconstructing the coupling constrained chain. The number and characteristic of the DOF of the equivalent mechanism are got using the modified G-K formula and the reciprocal screw theory, respectively. As a result, the kinematic characteristics of the tetrahedral element are known. The structure of the minimum composite unit and the large-scale truss deployable antenna are simplified, according to the equivalent mechanism and the combination of the tetrahedral elements. The numbers of the DOF of the minimum composite unit and the large-scale truss deployable antenna are derived on the basis of the geometric constraint equations. The simulation model for a deployable truss antenna assembled by 27 tetrahedral elements is built, and its DOF is verified. The result shows that the DOF of the antenna analyzed by the proposed method is correct. The method lays a foundation for further analysis of the kinematics and dynamics of similar type of antennas, providing a new idea for DOF analysis of other multi-loop coupling mechanisms. © 2017, Press of Chinese Journal of Aeronautics. All right reserved.

关键词： Antennas

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Deployable antenna mechanism with class of modular truss based on tetrahedral combination unit

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Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica 2020年第3期41卷 423219页

作者： Guo, Jinwei Huang, Zhirong Xu, Yundou Guo, Luyao Yao, Jiantao Zhao, Yongsheng Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao066004 China Xi'an710100 China Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of National Education Yanshan University Qinhuangdao066004 China

To solve the complex structure, the low folding rate, and the large number of motion pairs of the existing tetrahedral-based truss antenna mechanism, a class of new modular deployable structure is proposed based on the 3RR-3RRR tetrahedral combination unit and the 3RR-3URU tetrahedral symmetric combination unit. The modular structure consisting of three combination units is selected as the analysis object. First, the composition of the modular structure and the axis arrangement of the Hook hinges are introduced in detail, and the number and property of the Degree of Freedom (DOF) of the combination unit itself are obtained by applying the idea of link-demolishing-equivalent-restoration, the screw theory and the G-K formula. Second, the motion simulation of the two modular structures is carried out by using Adams dynamics simulation software. The simulation results verified the correctness of the DOF analysis. The folding rate of the mechanism is characterized by the ratio of the space volume occupied by the mechanism when fully unfolding and fully folding. The folding rates of the existing non-modular mechanisms and modular mechanisms based on tetrahedral unit are calculated. Finally, the number of DOF and motion pairs, the folding rate of non-modular mechanisms and modular mechanisms are compared and analyzed. The analysis results show that the modular structure based on the 3RR-3URU tetrahedral symmetrical combination unit can achieve a large folding rate, and the number of degree of freedom and motion pairs are also relatively reduced. In addition, fewer types of links are use when forming large antennas. The research results provide a theoretical basis for the design and analysis of such modular truss deployable antenna structures. © 2020, Press of Chinese Journal of Aeronautics. All right reserved.

关键词： Trusses

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Some mathematical aspects on walking robots stable evolution

Some mathematical aspects on walking robots stable evolution

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International Conference on Software, Knowledge Information, Industrial Management and Applications (SKIMA)

作者： Marcel Migdalovici Luige Vladareanu Gabriela Vladeanu Said Broumi Daniela Baran Florentin Smarandache Hongbo Wang Yonfei Feng Robotics and Mechatronics Department Romanian Academy Institute of Solid Mechanics Bucharest Romania Faculty of Science Ben M'Sik University Hassan II Casablanca Morocco Dynamical Systems National Institute of Aircraft Research “Elie Carafoli” Bucharest Romania Department of Mathematics University of New Mexico Gallup NM USA Parallel Robot and Mechatronic System Laboratory of Hebei Province Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Qinhuangdao China

ISBN: (纸本)9781509032990

A survey of some author's concepts on the dynamic systems stability regions, in the general case of dynamic systems that depend on parameters is related in the paper. The property of separation of stable regions in the free parameters domain is assumed in the paper as an important property of the environment that is carry out and in the specified case of walking robot analyzed in the paper. The matrix that defines the linear dynamic system has the components of the matrix, assumed to be with real values, and the matrices that intervene in the exposure of the method are also, with real values of the components. We assumed that the matrices from the exposure have the complex values such that the real values are also taken into account as particular case of the complex values. This hypothesis assures a new method of analysis, in the complex domain, on the dynamic systems stability. Our theory on the stability control of the dynamic systems is applied here for specified walking robot model that depend on parameters. The critical position of the walking robot evolution is defined and analyzed on some cases of the walking robot leg, and possible application for robot walking up stairs is exposed. The further way of research is emphasized.

关键词： Legged locomotion Eigenvalues and eigenfunctions Matrices Heuristic algorithms Stability analysis Mathematical model

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Effects of Structural Parameters on Hydraulic Performance of Flow Regulator

Effects of Structural Parameters on Hydraulic Performance of...

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CSAA/IET International Conference on Aircraft Utility Systems

作者： Yong Li Xuemei Zong Xiaoming Yuan Shiyi Zhao State Key Laboratory of Intelligent Manufacturing of Advanced Construction Machinery and Jiangsu Xuzhou Construction Machinery Research Institute Xuzhou Construction Machinery Group Co. Ltd Hebei Key Laboratory of Heavy Machinery Fluid Power Transmission and Control and with the Key Laboratory of Advanced Forging & Stamping Technology and Science Yanshan University

ISBN: (纸本)9781510872745

In order to evaluate the hydraulic performance of a regulator, the pressure loss and the stabilization performance of the regulator installed in the fire water monitor were introduced. The effects of structures on a regulator were investigated by the structural model made in UG and the flow simulation conducted in ANSYS. The hydraulic performance of a star-shaped regulator was analyzed with different structure parameters, such as the blade number, axial length and rounded-corner. The effects of structure parameters on the regulator were revealed, based on which the hydraulic performance of the improved regulator with different blade numbers was analyzed. The results show that the improved regulator with two cross-sections in dislocation and six even-distributed blades has the better hydraulic performance. The preliminary experimental results show that the improved regulator can improve the jet range of a fire water monitor.

关键词： Fire water monitor Hydraulic performance Regulator Flow simulation

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A Mechanical Model of Internal Expansion Over Bending and Calibration (Ieobc) Process For Large-Diameter Pipe End

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SSRN 2024年

作者： Qi, Shaocong Yu, Gaochao Shi, Zhaocheng Zhang, Zifeng Han, Yashuai Zhao, Feiping Li, Senlin Zhao, Jun Key Laboratory of Advanced Forging & Stamping Technology and Science Yanshan University Ministry of Education of China China Department of Mechanical Engineering Imperial College London LondonSW7 2AZ United Kingdom National-Local Joint Engineering Research Center for Advanced Manufacturing Forming Technology and Equipment Yanshan University China Hebei Engineering Technology Research Center of Metal Precision Plastic Processing Yanshan University China Nantong Chaoli Rolling Machine Producing Co. Ltd Nantong China

In the process of laying urban pipeline networks, it is necessary to cut the pipes, and the residual stress of the cut pipes is released, resulting in an increase in the ovality of the cut section. Therefore, roundness calibration of the pipe ends is required. The internal expansion over bend and calibration (IEOBC) process is an efficient technique used for on-site calibration of the ovality of pipe ends. To accurately analyze the deformation behavior of pipe ends and improve its ovality, the mechanical model of the IEOBC process is established based on the static equilibrium equation, elastic-plastic deformation physical equation, deformation coordination equation, and constraint equation, which can be regarded as a statically indeterminate problem. The variation law of the ovality in the pipe end cross-section during the calibration process is analyzed. A control strategy for pipe end IEOBC process was proposed based on the functional relationship between the ovality and relative displacement. Calibration experiments are conducted on a mobile intelligent calibration machine. After the IEOBC process, the pipe end cross-section with initial ovality of 2.31% and 2.69% was reduced to 0.18% and -0.31%, respectively, meeting the pipe specification of API SPEC 5L. The IEOBC process and the control strategy proposed in this study can be applied to the roundness calibration of pipe end cross-section during pipe installation. © 2024, The Authors. All rights reserved.

关键词： Expansion

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A through process modeling using multi-assistant software applied to radial fatigue life predication of a 356-T6 wheels

Research Square

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Research Square 2020年

作者： Duan, Yong-Chuan Zhang, Fang-Fang Tian, Le Guan, Ying-Ping Hu, Jin-Hua Key Laboratory of Advanced Forming & Stamping Technology and Science Ministry of Education of China Yanshan University Hebei Qinhuangdao066004 China College of Mechanical Engineering Yanshan University Hebei Qinhuangdao066004 China Technical Center CITIC Dicastal Limited company Hebei Qinhuangdao066004 China

In order to solve the problem of isolated design in multi-process using multi-assistant software, a through-software radial fatigue life prediction model was established, the effects of shrinkage cavity, SDAS and mean stress on fatigue life were considered. The casting process of the aluminum alloy wheel was simulated based on ProCast, and the data of SDAS and porosity of different parts were predicted based on the solidification process;The data mapping algorithm between tetrahedral mesh elements was developed to realize the unidirectional transformation of microcosmic data from a cast model to a static mechanical model, the radial loading mechanical analysis model of a wheel containing microcosmic information was established;The fatigue life prediction model was established by Fesafe based on the specific mechanical and fatigue parameters of each node. Based on the self-developed TCD software, the integrated coupling method of the three software prediction models was realized. The application of this method on the virtual fatigue prediction experiment of unidirectional tensile specimen reduce the result dispersion between virtual and physical experiment, and the predicted life result error is reduced from 51% to 16%. The proposed method lays a solid foundation of the optimization design and lightweight design of aluminum alloy wheels. © 2020, CC BY.

关键词： Wheels

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Enhanced Identification of Damage Evolution in Two-Dimensional Woven Laminated Materials Through Multimodal Information Fusion of Acousto-Optic-Force Data

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SSRN 2024年

作者： Zhang, Fangfang Xiao, Yang Duan, Yongchuan Xiao, Yuangan Wu, Honglin Zhu, Song Key Laboratory of Advanced Forming & Stamping Technology and Science Ministry of Education of China Yanshan University Hebei Qinhuangdao066004 China College of Mechanical Engineering Yanshan University Hebei Qinhuangdao066004 China Chongqing Hongjiang Machinery Co. Ltd. Chongqing402160 China

Non-destructive testing is a widely used inspection method for the safe maintenance of large composite structures. Acoustic signals and optical images, etc, are indirectly associated with damage. However, the complex damage modes of composites and the specific usage scenarios cause limitations, such as a modal signal that is stage-sensitive and selection-sensitive to the damage mode. This study proposes an advanced method to analyze the evolution of damage in composite materials using multimodal information fusion for enhanced identification while mitigating dispersion of recognition results. First, a experimental system is established with a synchronous data sampling logic. By combining mechanical, acoustic, and optical signals, we obtained a three-stage characteristic association of damage initiation, evolution, and instability of unidirectional stretching and three-point bending. Damage initiation identification was facilitated by distinguishability of the typical features, followed by combining the load and acoustic emission. The damage instability was determined by combining the optical and load signals. By combining the acoustic and load signals, the three damage modes and their corresponding peak frequency ranges were determined. Multimodal signals were combined to determine the association rules, laying a theoretical foundation for the reliable identification of multimodal and incomplete model damage in composites. © 2024, The Authors. All rights reserved.

关键词： Information fusion

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Improvement of the Microstructure and Microhardness of Az31 Mg Alloy Sheet by Cross-forging-Bending Repeated Deformation with Sharply Increasing Temperature

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SSRN 2023年

作者： Wei, Yuhui Lu, Liwei Li, Minhao Yang, Gongji Ma, Min Wang, Lifei Jing, Lei School of Mechanical Engineering Hunan University of Science and Technology Hunan Xiangtan411201 China School of Materials Science and Engineering Hunan University of Science and Technology Hunan Xiangtan411201 China Jiangsu Dayang Precision Forging Co. Ltd. Jiangsu Yancheng224000 China Key Laboratory of Interface Science and Engineering in Advanced Materials Northwest Institute for Nonferrous Metal Research Xi’an710016 China

In this work, the AZ31 Mg alloy sheet was subjected to a novel severe plastic deformation (SPD) process called forging-bending repeated deformation. The effect of the new process on the microstructure and microhardness of AZ31 magnesium alloy was investigated under increasing temperature treatment and a 90° cross route. The outcomes demonstrated that the effective strain rose as the number of passes increased. Due to the change of shear deformation direction, the flow uniformity was effectively improved. As the number of deformation passes increased, the average grain size was refined from 21.5 μm in the initial specimen to 1.6 μm in the specimen with 4 passes, and the microstructure became more uniform. The grain refinement was caused by the combined effect of discontinuous dynamic recrystallization (DDRX), continuous dynamic recrystallization (CDRX), and twinning-induced recrystallization (TDRX). The appearance of {10-12} extension twins contributed significantly to both coarse grain subdivision and coordinated plastic deformation. In addition, the activation of pyramidal slip was devoted to the improvement of the plasticity of magnesium alloys. After four passes of deformation, the microhardness of the magnesium alloy specimens could reach 81.9 HV, and the rise in hardness is mostly influenced by fine grain strengthening and dislocation strengthening. © 2023, The Authors. All rights reserved.

关键词： Microstructure

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Design and experimental study of the remote control for a novel patient transfer apparatus

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Journal of Physics: Conference Series 2021年第6期1748卷

作者： Yu Tian Hongbo Wang Yongshun Zhang Junjie Tian Jiazheng Du Parallel Robot and Mechatronic System Laboratory of Hebei Province Yanshan University Qinhuangdao Hebei China Key Laboratory of Advanced Forging & Stamping Technology and Science of Ministry of Education Yanshan University Qinhuangdao Hebei China

This paper introduces the design of the remote control for a novel patient transfer apparatus. First, the overall design of the control system is put forward based on the working principle, and design requirements of the apparatus. Second, voltage regulator circuit of the remote control based on the MC34063 is designed to fit for the OLED displayer, parameters such as the filter capacitor have been determined. Next, wireless communication unit adopted CC1110 and the communication instruction code is introduced. Then, the interaction interface of the remote control is finished to facilitate the implementation of the adjustment functions. finally, a simulation and a real experiment has been completed, it indicates the correctness of the voltage regulator circuit and the effectiveness of the remote control respectively.

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