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Defence Technology（防务技术） 2020年第2期16卷 417-424页

作者： Ting-ting Yin Fang-xiu Jia Xiao-ming Wang ZNDY of Ministerial Key Laboratory Nanjing University of Science and TechnologyNanjing210094China

Phase-frequency characte ristics of approximate sinusoidal geomagnetic signals can be used fo r projectile roll positioning and other high-precision trajectory correction applications.The sinusoidal geomagnetic signal deforms in the exposed and magnetically contaminated environment.In order to preciously recognize the roll information and effectively separate the noise component from the original geomagnetic sequence,based on the error source analysis,we propose a moving horizon based wavelet de-noising method for the dual-observed geomagnetic signal filtering where the captured rough roll frequency value provides reasonable wavelet decomposition and reconstruction level selection basis for sampled sequence;a moving horizon window guarantees real-time performance and non-cumulative calculation amount.The complete geomagnetic data in full ballistic range and three intercepted paragraphs are used for performance assessment.The positioning performance of the moving horizon wavelet de-noising method is compared with the band-pass filter.The results show that both noise reduction techniques improve the positioning accuracy while the wavelet de-noising method is always better than the band-pass filter.These results suggest that the proposed moving horizon based wavelet de-noising method of the dual-observed geomagnetic signal is more applicable for various launch conditions with better positioning performance.

关键词： High-spin projectile roll positioning Dual-observed geomagnetic signal Wavelet de-noising Discrete wavelet transform

Microstructural and textural evolutions in multilayered Ti/Cu composites processed by accumulative roll bonding

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Journal of Materials Science & Technology 2019年第6期35卷 1165-1174页

作者： Shuang Jiang Ru Lin Peng Nan Jia Xiang Zhao Liang Zuo Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education) School of Material Science and Engineering Northeastern UniversityShenyang 110819 China Department of Mechanical Engineering Linkoping University Linkoping 58183 Sweden

Ti/Cu multilayered composites were fabricated via accumulative roll bonding(ARB). During codeformation of the constituent metals, the hard Ti layers necked preferentially and then fragmented with the development of shear bands. Transmission electron microscopy showed that with increasing ARB cycles, grains in Ti were significantly refined even though dynamic recrystallization has occurred. For Cu the significant grain refinement was only found within the shear banded region when the composite was processed after five ARB cycles. Due to the diffusion of Cu atoms into Ti at the heterophase interfaces, amorphization with a width less than 10 nm was identified even in the composite processed by one cycle. At higher ARB cycles, the width of amorphous region increased and intermetallic compounds CuTi appeared from the region. The lattice defects introduced at the heterophase interfaces under roll bonding was responsible for the formation of the nano-scaled compounds. X-ray diffraction showed that an abnormal {1120} fiber texture was developed in Ti layers, while significant brass-type textures were developed in Cu layers. Some orientations along the {1120} fiber favored the prismatic slip for Ti.Tensile tests revealed the elevated strength without a substantial sacrifice of ductility in the composites during ARB. The unique mechanical properties were attributed to the significantly refined grains in individual metals, the good bonding between the constituent metals, as well as the development of an abnormal {1120} fiber texture in Ti layers.

关键词： Titanium/copper multilayered composite Accumulative roll bonding Microstructure Texture Mechanical properties

Effect of annealing treatment on microstructure and mechanical properties of Al/Ni multilayer composites during accumulative roll bonding (ARB) process

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Journal of Iron and Steel Research(International) 2020年第1期27卷 96-104页

作者： Hui-wen Zhu Bao-yi Yu Hao Zhang Bo-ning Yu Shu-ning Lv Li Zheng Run-xia Li School of Material Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808GuangdongChina

Al/Ni multilayer composites are produced by accumulative roll bonding process and then annealed with different temperatures and time.Macroscopic images,microstructure and mechanical properties of Al/Ni multilayer composites are investigated.As for the macroscopic images,although there was an edge crack along the rolling direction at the third pass,the defect of composites was not serious and the forming quality of composites was relatively good.The yield strength and elongation of Al/Ni multilayer composites are improved after the annealing treatment;however,with the increase in annealing temperature and time,the yield strength and ciongation of Al/Ni multilayer composites are decreased.During the process of annealing treatment,aluminum atoms diffuse in the way of vacancy diffusion,which results in the formation of Al3Ni intermetallic phase at Al/Ni interface and Kirkendall void in the aluminum side.The content of Al3Ni intermetallic phase and Kirkenckill void would increase with the increase in annealing temperature and time.

关键词： Al/Ni multilayer composite Accumulative roll bonding process Annealing treatment Interrnetallic phase

Vehicle roll stability control with active roll-resistant electro-hydraulic suspension

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Frontiers of Mechanical Engineering 2020年第1期15卷 43-54页

作者： Lijun XIAO Ming WANG Bangji ZHANG Zhihua ZHONG State Key Laboratory of Advanced Design and Manufacture for Vehicle Body Hunan UniversityChangsha 410082China

This study examines roll stability control for vehicles with an active roll-resistant electro-hydraulic suspension(RREHS)subsystem under steering maneuvers.First,we derive a vehicle model with four degrees of freedom and incorporates yaw and roll motions.Second,an optimal linear quadratic regulator controller is obtained in consideration of dynamic vehicle performance.Third,an RREHS subsystem with an electric servo-valve actuator is proposed,and the corresponding dynamic equations are obtained.Fourth,field experiments are conducted to validate the performance of the vehicle model under sine-wave and double-lane-change steering maneuvers.Finally,the effectiveness of the active RREHS is determined by examining vehicle responses under sine-wave and double-lane-change maneuvers.The enhancement in vehicle roll stability through the RREHS subsystem is also verified.

关键词： electro-hydraulic suspension roll stability LQR experiment

FEM simulation of flexible roll forming based on different material models

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High Technology Letters 2018年第4期24卷 434-439页

作者：管延智 Yan Yu Wang Haibo College of Mechanical and Electrical Engineering North China University of Technology

Flexible roll forming is a new roll forming process that produces parts with variable cross sections. This forming process is proposed to meet the demand of weight reduction of automobile industry. In order to study the mechanisms and material flow rules in this new forming process,the finite element mothod( FEM) model of a nine-step flexible roll forming of an ultra-high-strength steel bumper is established based on deep understanding and reasonable simplification of the process.Given that the material model is an important factor that influences the simulation accuracy,three material models which consist of different yield criteria and hardening models are adopted in the FEM models. Sheet thickness and springback amount calculated with three material models are studied comparatively. According to sheet thickness reduction and springback amounts,it is found that the MKi( Mises yield criterion and kinematic hardening law) model's result is larger than MI( Mises yield criterion and isotropic hardening law) model and HI( Hill's yield criterion and isotropic hardening law) model. Therefore,it is concluded that material models do have influences on the flexible roll forming simulation and need to be determined carefully.

关键词： flexible roll forming finite element mothod(FEM)modeling material model ultra-high-strength steel

Experimental investigation of influence of strake wings on self-induced roll motion at high angles of attack

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Chinese Journal of Aeronautics 2016年第6期29卷 1591-1601页

作者： Geng Xi Shi Zhiwei Cheng Keming College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics

The modern high performance air vehicles are required to have extreme maneuverability,which includes the ability of controlled maneuvers at high angle of attack. However, the nonlinear and unsteady aerodynamic phenomena, such as flow separation, vortices interaction, and vortices breaking down, will occur during the flight at high angle of attack, which could induce the uncommanded motions for the air vehicles. For the high maneuverable and agile air missile, the nonlinear roll motions would occur at the high angle of attack. The present work is focused on the selfinduced nonlinear roll motion for a missile configuration and discusses the influence of the strake wings on the roll motion according to the results from free-to-roll test and PIV measurement using the models assembled with different strake wings at a = 60°. The free-to-roll results show that the model with whole strake wings(baseline), the model assembled with three strake wings(Case A)and the model assembled with two opposite strake wings(Case C) experience the spinning, while the model assembled with two adjacent strake wings(Case B), the model assembled with one strake wing(Case D) and the model with no strake wing(Case E) trim or slightly vibrate at a certain "×"rolling angle, which mean that the rolling stability can be improved by dismantling certain strake wings. The flow field results from PIV measurement show that the leeward asymmetric vortices are induced by the windward strake wings. The vortices would interact the strake wings and induce crossflow on the downstream fins to degrade the rolling stability of the model. This could be the main reason for the self-induced roll motion of the model at a = 60°.

关键词： Cruciform fins High angle of attack PIV roll motion Strake wing

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1235铝合金连续铸轧态微观组织的表征

中国有色金属学报 2014年第4期24卷 863-869页

作者：毛宏亮王剑华杨钢史庆南易健宏陈亮维昆明理工大学材料科学与工程学院昆明650093 云南省昆明冶金研究院材料研究所昆明650031

采用连续铸轧方法制备6 mm厚、牌号为1235的铝合金，利用高分辨透射电镜（TEM）、扫描电镜（SEM）和背散射电子衍射技术（EBSD）对铸轧态（TRC）样品的微观结构进行表征。结果表明：铸轧态的1235铝合金具有快速凝固组织，即晶粒尺寸在30... 详细信息

采用连续铸轧方法制备6 mm厚、牌号为1235的铝合金，利用高分辨透射电镜（TEM）、扫描电镜（SEM）和背散射电子衍射技术（EBSD）对铸轧态（TRC）样品的微观结构进行表征。结果表明：铸轧态的1235铝合金具有快速凝固组织，即晶粒尺寸在30-100 nm之间的纳米多晶组织，有沿（）晶面滑移的滑移带和高密度位错线等深度塑性变形组织，还有沿（100）晶面生长的再结晶组织；Fe和Si等掺杂元素固溶在基体Al中；在铸轧态下晶粒直径几乎分布在20-50μm之间，且产生的较强织构有{210}〈122〉、{122}〈210〉和{210}〈125〉等，较弱的织构有铜织构{112}〈111〉和{112}〈110〉。

关键词： 1235铝合金连续铸轧微观结构高分辨透射电镜电子背散射衍射织构 twin roll casting(TRC) backscattered electron diffraction(EBSD)

Microstructure and mechanical properties of Al/Cu/Mg laminated composite sheets produced by the ARB proces

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 564-572页

作者： Davood Rahmatabadi Moslem Tayyebi Ramin Hashemi Ghader Faraji School of Mechanical Engineering Iran University of Science and Technology Department of Materials Engineering Sahand University of Technology School of Mechanical Engineering College of EngineeringUniversity of Tehran

In the present study, an Al/Cu/Mg multi-layered composite was produced by accumulative roll bonding(ARB) through seven passes, and its microstructure and mechanical properties were evaluated. The microstructure investigations show that plastic instability occurred in both the copper and magnesium reinforcements in the primary sandwich. In addition, a composite with a perfectly uniform distribution of copper and magnesium reinforcing layers was produced during the last pass. By increasing the number of ARB cycles, the microhardness of the layers including aluminum, copper, and magnesium was significantly increased. The ultimate tensile strength of the sandwich was enhanced continually and reached a maximum value of 355.5 MPa. This strength value was about 3.2, 2, and 2.1 times higher than the initial strength values for the aluminum, copper, and magnesium sheets, respectively. Investigation of tensile fracture surfaces during the ARB process indicated that the fracture mechanism changed to shear ductile at the seventh pass.

关键词： multi-layered composite Al/Cu/Mg accumulative roll bonding fractography mechanical properties microstructure

Chemical Compositions,Microstructure and Mechanical Properties of roll Core used Ductile Iron in Centrifugal Casting Composite rolls

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Journal of Materials Science & Technology 2012年第9期28卷 853-858页

作者： Yunlong Bai Yikun Luan Nannan Song Xiuhong Kang Dianzhong Li Yiyi Li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The industrial manufacture processes of three kinds of roll core used ductile irons have been investigated via systematical experiments. EfFects of the ratio of C/Si, pig iron, nodularizer and alloying method on the microstructure and mechanical properties of the heavy section ductile iron have been analyzed. It has been found that when treated with RE-Mg plus Sb, high quality nodular castings can be produced even if much anti spheroidizing alloy elements are included in the pig iron. The alloy element Sb played an important role in the control of graphite morphology.

关键词： Centrifugal casting roll Heavy section ductile iron Micro-alloying with Sb

Sym ZS roll系统在卷烟纸机上的应用

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中国造纸 2017年第2期36卷 45-48页

作者：刘娜牡丹江恒丰纸业股份有限公司黑龙江牡丹江157013

结合Sym ZS roll系统在牡丹江恒丰纸业股份有限公司16~#卷烟纸机的使用情况,详细介绍Sym ZS roll系统工作原理和技术特点,以及相关设备的功能特点和重点维护事项。

关键词： Sym ZS roll 雕印液压站比例阀