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Chinese Journal of Aeronautics 2018年第1期31卷 178-186页

作者： zhengcai zhao Jiuhua XU Yucan FU Zhiqiang LI College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China Beijing Aeronautics Manufacturing Technology Research Institute Beijing 100024 China

Titanium hollow blades are characterized with lightweight and high structural strength, which are widely used in advanced aircraft engines nowadays. Superplastic forming/diffusion bonding （SPF/DB） combined with numerical control （NC） milling is a major solution for manufacturing titanium hollow blades. Due to the shape deviation caused by multiple heat and pressure cycles in the SPF/DB process, it is hard to manufacture the leading and tailing edges by the milling process. This paper presents a new adaptive machining approach using free-form deformation to solve this problem. The actual SPF/DB shape of a hollow blade was firstly inspected by an on-machine measurement method. The measured point data were matched to the nominal SPF/DB shape with an improved ICP algorithm afterwards, by which the point-pairs between the measurement points and their corresponding points on the nominal SPF/DB shape were established, and the maximum modification amount of the final nominal shape was constrained. Based on the displacements between the point-pairs, an accurate FFD volume was iteratively calculated. By embedding the final nominal shape in the deformation space, a new final shape of the hollow blade was built. Finally, a series of measurement and machining tests was performed, the results of which validated the feasibility of the proposed adaptive machining approach.

关键词： Adaptive machining Blade geometry Free-form deformation Reconstruction Titanium

Neck-spinning quality analysis and optimization of process parameters for plunger components:Simulation and experimental study

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Chinese Journal of Aeronautics 2021年第4期34卷 174-191页

作者： Yang WANG Honghua SU Ning QIAN Kui LIU Jianbo DAI zhengcai zhao Wenfeng DING College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China Singapore Institute of Manufacturing Technology 73 Nanyang DriveSingapore 637662Singapore School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China

The plunger component is a key part of the plunger pump in the aircraft hydraulic ***-spinning process is commonly used to fabricate plunger components,of which the quality of the spinning process significantly affects the performance of plunger *** of the bottlenecks faced by the industry in the spinning process is to choose a suitable neck-spinning process so as to ensure the quality of plunger *** is necessary to propose a reliable method to optimize the process parameters which affect the neck-spinning quality of plunger *** this study,a calculable finite element analysis(FEA)model is established to simulate the threeroller neck-spinning process of the plunger component,which includes six typical slipper structures,two roller structures,and two spinning *** FEA model is then validated by comparing the simulated spinning forces with the corresponding experimental *** influence of the process conditions on the neck-spinning quality is *** the orthogonal simulation results are analyzed by a combination of range method and fuzzy mathematical analysis method to recommend a reasonable slipper structure,roller structure and neck-spinning *** study provides a promising method to improve the manufacturing quality of the typical plunger components.

关键词： Fuzzy method Neck-spinning quality Plunger component Range analysis Simulation

Mechanical Janus lattice with plug-switch orientation

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 23-26页

作者： Yupei Zhang Jiawei Zhong zhengcai zhao Ruiyu Bai Yanqi Yin Yang Yu Bo Li State Key Laboratory for Manufacturing System EngineeringShaanxi Key Laboratory of Intelligent Robots School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Qian Xuesen Honors College Xi’an Jiaotong UniversityXi’an 710049China

In recent years,materials with asymmetric mechanical response properties(mechanical Janus materials)have been found possess numerous potential applications,*** absorption and vibration *** this study,we propose a novel mechanical Janus lattice whose asymmetric mechanical response can be switched in orientation by a *** finite element analysis and experimental verification,this lattice exhibits asymmetric displacement responses to symmetric ***,with such a plug structure inside,individual lattices can switch the orientation of asymmetry and thus achieve reprogrammable design of a mechanical structure with chained *** reprogrammable asymmetry of this material will offer multiple functions in design of mechanical metamaterials.

关键词： Janus Non-reciprocity Programmability Mechanical metamaterial

Collaborative manufacturing technologies of structure shape and surface integrity for complex thin-walled components of aero-engine:Status,challenge and tendency

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Chinese Journal of Aeronautics 2023年第7期36卷 1-24页

作者： Biao zhao Wenfeng DING Zhongde SHAN Jun WANG Changfeng YAO zhengcai zhao Jia LIU Shihong XIAO Yue DING Xiaowei TANG Xingchao WANG Yufeng WANG Xin WANG College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China AVIC Manufacturing Technology Institute Beijing 100024China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China AECC Shenyang Liming Aero-engine Co. LTD.Shenyang 110000China

Presently,the service performance of new-generation high-tech equipment is directly affected by the manufacturing quality of complex thin-walled components.A high-efficiency and quality manufacturing of these complex thin-walled components creates a bottleneck that needs to be solved urgently in machinery *** address this problem,the collaborative manufacturing of structure shape and surface integrity has emerged as a new process that can shorten processing cycles,improve machining qualities,and reduce *** paper summarises the research status on the material removal mechanism,precision control of structure shape,machined surface integrity control and intelligent process control technology of complex thin-walled *** solutions and technical approaches are then put forward to solve the critical problems in the high-performance manufacturing of complex thin-wall *** development status,challenge and tendency of collaborative manufacturing technologies in the high-efficiency and quality manufacturing of complex thin-wall components is also discussed.

关键词： Collaborative manufacturing of shape and performance Complex thin-walled component Intelligent process control Material removal mechanism Surface integrity

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勤务指挥体系建设构想和实践

江苏警官学院学报 2010年第2期25卷 177-179页

作者：赵正才江苏省泗洪县公安局

公安部门应构建扁平化勤务指挥体系,坚持"信息与情报、指挥与指导、防控与打击"相结合的理念,在总体设计上,更新指挥理念;在目标追求上,紧贴一线实战,实现"四个转变";在具体运用上,以基层最小作战单元为载体,做到指挥到岗、指挥到点。

关键词：勤务指挥体系警务公安工作

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切削加工有限元仿真技术的现状与展望

南京航空航天大学学报 2023年第3期55卷 361-378页

作者：苏宏华王禹封谯木赵正彩赵彪徐宝德南京航空航天大学机电学院南京210016 北京星航机电装备有限公司北京100071

切削加工有限元仿真是采用数值方法模拟切削加工过程的技术,可以研究切削加工过程中材料去除引发的各种物理机制,在优化切削参数、提高加工质量、降低研究成本等方面具有显著优势。如何使切削加工有限元仿真与实际的切削加工更加吻合是... 详细信息

切削加工有限元仿真是采用数值方法模拟切削加工过程的技术,可以研究切削加工过程中材料去除引发的各种物理机制,在优化切削参数、提高加工质量、降低研究成本等方面具有显著优势。如何使切削加工有限元仿真与实际的切削加工更加吻合是研究的热点,为此国内外开展了众多切削加工有限元仿真技术的研究工作,相关成果已在多种关键部件的切削加工中得到工程应用。本文概述了切削加工有限元仿真的几何仿真和物理仿真各自的基本原理、优势和发展趋势,系统总结了国内外学者为了提高切削加工有限元仿真的精度和效率,在本构模型和网格划分方面所开展工作的发展现状,综述了切削加工全过程动态仿真方法的研究进展,并对切削加工有限元仿真技术的重要问题和未来发展趋势进行了展望。

关键词：切削加工本构模型网格细化几何仿真

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基于近似模型的装夹应力场虚拟映射方法研究

航空制造技术 2023年第21期66卷 67-73页

作者：王禹封赵正彩苏宏华陈燕徐宝德南京航空航天大学南京210016 北京星航机电装备有限公司北京100071

切削加工过程中材料内部残余应力是影响加工质量的关键因素之一,在虚拟环境实现应力场演化过程的可视化能有效监测其演化规律,有助于提高零件加工质量。为实现应力场在虚拟环境的实时映射,依据数字孪生技术开发了一种装夹应力场实时映... 详细信息

切削加工过程中材料内部残余应力是影响加工质量的关键因素之一,在虚拟环境实现应力场演化过程的可视化能有效监测其演化规律,有助于提高零件加工质量。为实现应力场在虚拟环境的实时映射,依据数字孪生技术开发了一种装夹应力场实时映射方法。首先,阐明了切削加工系统数字孪生层级。然后,提出了加工过程残余应力场在虚拟环境的映射方案,具体为:基于有限元仿真方法,采用RBF神经网络建立了应力场仿真近似模型;以孪生几何模型为载体,采用数据驱动方法实现了近似模型仿真结果在虚拟环境的映射。最后,以工件装夹残余应力场分布情况为例进行验证。结果表明,近似模型实时仿真结果与有限元仿真结果的最大偏差为7.7%,验证了该应力场虚拟映射方法的可行性与有效性,为切削加工过程数字孪生提供了技术支撑。

关键词：数字孪生切削加工装夹残余应力场近似模型数据驱动

基于有限差分模型的磨削弧区流场动压力数值分析

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金刚石与磨料磨具工程 2017年第1期37卷 19-24页

作者：茅暑杰徐九华赵正彩傅玉灿南京航空航天大学机电学院南京210016

磨削弧区动压力对通过磨削区磨削液的有效流量、润滑和冷却作用有重要影响。本研究基于流体动压理论,建立了磨削弧区的动压力分布数学模型,将微分方程简化至近似泊松方程形式后,采用有限差分法将连续方程离散化,得出了磨削区动压力的数... 详细信息

磨削弧区动压力对通过磨削区磨削液的有效流量、润滑和冷却作用有重要影响。本研究基于流体动压理论,建立了磨削弧区的动压力分布数学模型,将微分方程简化至近似泊松方程形式后,采用有限差分法将连续方程离散化,得出了磨削区动压力的数值解,并提出了迭代优化算法,提高了计算效率。将砂轮特性参数纳入数学模型之中,可根据砂轮材质、砂轮与工件间隙、砂轮转速等参数预报磨削弧区的磨削液动压力分布。在此理论模型基础上,进行了验证实验,证明模型的科学性。结果表明:通过输入砂轮各项参数,该模型可以快速、准确地预报动压力的分布,为磨削加工提供参考。

关键词：流体动压力磨削泊松方程有限差分法

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越野车驱动桥壳的轻量化设计与开发

汽车实用技术 2018年第1期44卷 76-80页

作者：赵正彩范亘徐进金北京汽车研究总院有限公司底盘部北京101300

文章主要介绍了越野车驱动桥壳的轻量化设计、板材选取及桥壳成型开发过程,通过多轮试验对比,确定可行的实现方案,为量产车型的节能、降耗提供可能的边际贡献。

关键词：驱动桥壳本体轻量化研究与应用

航空航天难加工材料切削加工过程模拟与智能控制综述

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航空制造技术 2023年第3期66卷 14-29页

作者：赵彪王欣陈涛丁文锋傅玉灿徐九华赵正彩陈清良南京航空航天大学南京210016 航空工业成都飞机工业(集团)有限责任公司成都610092

随着航空航天关键构件服役性能要求的不断提升,高性能钛合金、镍基高温合金、高强度钢等难加工材料大量应用到航空发动机等重大装备。切削加工是高强韧难加工材料的重要加工方法,在加工过程中普遍存在切削力大、切削温度高、工具磨损严... 详细信息

随着航空航天关键构件服役性能要求的不断提升,高性能钛合金、镍基高温合金、高强度钢等难加工材料大量应用到航空发动机等重大装备。切削加工是高强韧难加工材料的重要加工方法,在加工过程中普遍存在切削力大、切削温度高、工具磨损严重和加工质量差的问题。针对当前航空航天难加工材料切削加工过程切削力、切削温度、工具磨损及表面质量的仿真技术与智能控制技术进行了系统性的总结和梳理,分析了当前研究存在的主要问题与关键挑战,对切削加工过程仿真模拟与控制技术的未来发展趋势进行了展望。

关键词：有限元仿真智能控制切削力切削温度刀具磨损表面完整性