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Formability of Fe-Mn-C Twinning Induced Plasticity Steel

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Journal of Iron and Steel Research International 2013年第11期20卷 111-117页

作者： HUANG Yao zhao ai-min MI Zhen-li JING Hai-tao LI Wen-yuan HUI Ya-jun Engineering Research Institute University of Science and Technology Beijing ME Department SaiC Motor Passenger Vehicle Co. Shougang Research Institute of Technology

A comparative analysis of formability was investigated between F^Mn-C twinning induced plasticity steel with different Mn contents and interstitial free steel. Tensile test combing with the morphology of fracture reveals that element Mn is helpful for the forming of inclusion or particles with film or rod shapes inducing the crack initia- tion and propagation. During stamping process, twinning induced plasticity steel without earing shows better anisot- ropy than interstitial-free steel because a typical 〈111〉 fiber texture forms accompanied by a weaker 〈100〉 fiber texture. The difference between the two steels is not evident during Erichsen cone cupping test, but the result of cone cupping test indicates that the twinning induced plasticity steel has superior drawing ability compared with intersti tial-free steel. The different performances can be attributed to the different deformation mechanism during cupping test. FED （forming limit diagram） of tested steels further suggests twinning induced plasticity steel has slightly su- perior deep drawability but low stretchability than that of IF steel, whose FLD0 value can reach 30%.

关键词： TWIP steel earing cone cupping forming limit diagram

Investigation of lateral-directional aerodynamic parameters identification method for fly-by-wire passenger airliners

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Chinese Journal of Aeronautics 2014年第4期27卷 781-790页

作者： Wu zhao Wang Lixin Lin Jiaming ai Junqiang School of Aeronautic Science and Engineering Beihang University

A new identification method is proposed to solve the problem of the influence on the loaded excitation signals brought by high feedback gain augmentation in lateral-directional aerodynamic parameters identification of fly-by-wire（FBW） passenger airliners. Taking for example an FBW passenger airliner model with directional relaxed-static-stability, through analysis of its signal energy distribution and airframe frequency response, a new method is proposed for signal type selection, signal parameters design, and the appropriate frequency relationship between the aileron and rudder excitation signals. A simulation validation is presented of the FBW passenger airliner＇s lateral-directional aerodynamic parameters identification. The validation result demonstrates that the designed signal can excite the lateral-directional motion mode of the FBW passenger airliner adequately and persistently. Meanwhile, the relative errors of aerodynamic parameters are less than 5%.

关键词： Excitation signal design Flight test Fly-by-wire (FBW)passenger airliner High feedback gain augmentation Identification Lateral-directional aerodynamic parameter

Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第01期 337-349页

作者： Meiyun Xu Song Gu Fulong Chen Zhe zhao Peng Liu Daoben Hua State Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

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Infrared microspectroscopy beamline BL06B at SSRF

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Nuclear Science and Techniques 2024年第1期35卷 10-17页

作者： Te Ji Hua-Chun Zhu Wei-Wei Peng Jie Wang Hong-Wei zhao ai-Guo Li min Chen Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

The infrared microspectroscopy beamline(BL06B) is a phase Ⅱ beamline project at the Shanghai Synchrotron Radiation Facility(SSRF). The construction and optical alignment of BL06B were completed by the end of 2020. By 2021, it became accessible to users. The synchrotron radiation infrared(SRIR) source included edge radiation(ER) and bending magnet radiation(BMR). The extracted angles in the horizontal and vertical directions were 40 and 20 mrad, respectively. The photon flux, spectral resolution, and focused spot size were measured at the BL06B endstation, and the experimental results were consistent with theoretical calculations. SRIR light has a small divergence angle, high brightness, and a wide wavelength range. As a source of IR microscopy, it can easily focus on a diffraction-limited spatial resolution with a high signal-to-noise ratio(SNR). The BL06B endstation can be applied in a wide range of research fields, including materials, chemistry, biology, geophysics, and pharmacology.

关键词： Synchrotron radiation Infrared beamline Infrared microspectroscopy

Modified constitutive models for Inconel 718 considering current density and temperature in electrically assisted forming process

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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan CUI Rui zhao min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Local Structure Determination of Mn^(2+)-Doped Fluoride Crystals by Superhyperfine Splitting Measurements

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Chinese Physics Letters 1998年第1期15卷 43-45页

作者： zhao min-guang Institute of Solid State Physics Sichuan Normal UniversityChengdu 610068

A procedure is presented for the calculation of the Mn^(2+)-F^(-) bond length from the superhyperfine constants measured by magnetic resonance *** the present technique it is possible to detect the variation of the bond length,ΔR,down to 0.01Å.The technique is sensitive enough to determine the bond length R and its variationΔR experienced when pressure or temperature changes.

关键词： hyperfine constants bond

Consensus of switched multi-agent systems with binary-valued communications

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Science China(Information Sciences) 2022年第6期65卷 189-202页

作者： min HU Ting WANG Yanlong zhao The Key Laboratory of Systems and Control Institute of Systems Science Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

This paper studies the consensus of switched multi-agent systems(MAS) with binary-valued communications. Different from the existing studies on switched MAS considering precise observations,each agent studied in this research only receives binary-valued information with stochastic noises from its neighbors’ states. Further, unlike the existing studies on MAS with binary-valued information in a fixed topology, in this paper, we consider the jointly connected undirected graphs, each of which switches with non-zero probability. The consensus algorithm comprises of two stages: first, the connected agents employ a recursive projection algorithm to estimate their neighbors’ states based on the binary-valued communications;second, the control law of the connected agents is developed based on the estimations to upgrade their *** is proved that both the speed of the estimation convergence to the real states and the consensus speed of the states can achieve O(1/t) when the iteration step is given a proper value. Furthermore, the results indicate that the larger the value of the lowest probability that a graph emerges with, the more easily the consensus could be achieved. Finally, a simulation is presented to demonstrate the theoretical analysis.

关键词： binary-valued system switched multi-agent system recursive projection algorithm consensus jointly connected undirected topologies

Nanometric Cutting Mechanism of Cerium-Lanthanum Alloy

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 155-166页

作者： Chenyu zhao min Lai Fengzhou Fang State Key Laboratory of Precision Measuring Technology&Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072China Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland

Cerium-lanthanum alloy is widely used in the green energy industry,and the nanoscale smooth surface of this material is in *** cutting is an effective approach to achieving the ultra-precision machining *** dynamics(MD)simulation is usually used to reveal the atomic-scale details of the material removal mechanism in nanometric *** this study,the effects of cutting speed and undeformed chip thickness(UCT)on cutting force and subsurface deformation of the cerium-lanthanum alloy during nanometric cutting are analyzed through MD *** results illustrate that the dislocations,stacking faults,and phase transitions occur in the subsurface during *** dislocations are mainly Shockley partial dislocation,and the increase of temperature and pressure during the cutting process leads to the phase transformation ofγ-Ce(FCC)intoβ-Ce(HCP)andδ-Ce(BCC).β-Ce is mainly distributed in the stacking fault area,whileδ-Ce is distributed in the boundary area between the dislocation atoms andγ-Ce *** cutting speed and UCT affect the distribution of subsurface damage.A thicker deformed layer including dislocations,stacking faults and phase-transformation atoms on the machined surface is generated with the increase in the cutting speed and ***,the cutting speed and UCT significantly affect the cutting force,material removal rate,and generated subsurface *** fluctuations in the cutting force are related to the generation and disappearance of *** research first studied the nanometric cutting mechanism of the cerium-lanthanum ally,providing a theoretical basis for the development of ultra-precision machining techniques of these materials.

关键词： Cerium-lanthanum alloy Molecular dynamics simulation Nanometric cutting Subsurface damage

Optimal filtering for uncertain systems with stochastic nonlinearities, correlated noises and missing measurements

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1052-1059页

作者： Shuo Zhang Yan zhao min Li Jianhui zhao School of Instrument Science and Opto-electronics Engineering Beihang University

The globally optimal recursive filtering problem is studied for a class of systems with random parameter matrices,stochastic nonlinearities, correlated noises and missing measurements. The stochastic nonlinearities are presented in the system model to reflect multiplicative random disturbances, and the additive noises, process noise and measurement noise, are assumed to be one-step autocorrelated as well as two-step cross-correlated.A series of random variables is introduced as the missing rates governing the intermittent measurement losses caused by unfavorable network conditions. The aim of the addressed filtering problem is to design an optimal recursive filter for the uncertain systems based on an innovation approach such that the filtering error is globally minimized at each sampling time. A numerical simulation example is provided to illustrate the effectiveness and applicability of the proposed algorithm.

关键词： globally optimal recursive filtering random parameter matrices stochastic nonlinearities correlated noises missing measurements