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Chinese Journal of Mechanical Engineering 2024年第2期37卷 264-282页

作者： Xin Pan xiancheng zhang Zhinong Jiang Guangfu Bin Beijing Key Laboratory of Health Monitoring and Self-recovery for High-End Mechanical Equipment College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Engine Health Monitoring-Control and Networking(Ministry of Education) College of Mechanical and Electrical EngineeringBeijing University of Chemical TechnologyBeijing 100029China College of Mechanical Engineering Hunan University of Science and TechnologyXiangtan 411201China

The co-frequency vibration fault is one of the common faults in the operation of rotating equipment,and realizing the real-time diagnosis of the co-frequency vibration fault is of great significance for monitoring the health state and carrying out vibration suppression of the *** engineering scenarios,co-frequency vibration faults are highlighted by rotational frequency and are difficult to identify,and existing intelligent methods require more hardware conditions and are exclusively ***,Lightweight-convolutional neural networks(LW-CNN)algorithm is proposed in this paper to achieve real-time fault *** critical parameters are discussed and verified by simulated and experimental signals for the sliding window data augmentation *** on LW-CNN and data augmentation,the real-time intelligent diagnosis of co-frequency is ***,a real-time detection method of fault diagnosis algorithm is proposed for data acquisition to fault *** is verified by experiments that the LW-CNN and sliding window methods are used with high accuracy and real-time performance.

关键词： Co-frequency vibration Real-time diagnosis LW-CNN Data augmentation

Improvement of titanium alloy TA19 fatigue life by submerged abrasive waterjet peening:Correlation of its process parameters with surface integrity and fatigue performance

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Chinese Journal of Aeronautics 2024年第1期37卷 377-390页

作者： Gongyu WANG Shulei YAO Yuxin CHI Chengcheng zhang Ning WANG Yalong CHEN Rongsheng LU Zhuang LI xiancheng zhang Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China AECC Commercial Aircraft Engine Co.LTD Shanghai Engineering Research Center for Commercial Aircraft EngineShanghai 201108China

Submerged abrasive waterjet peening(SAWJP)is an effective anti-fatigue manufacturing technology that is widely used to strengthen aeroengine *** study investigated the correlation of SAWJP process parameters on surface integrity and fatigue life of titanium alloy *** with different water pressures and standoff distances(SoDs)was conducted on the TA19 *** surface integrity of the specimens before and after SAWJP with different process parameters was experimentally studied,including microstructure,surface roughness,microhardness,and compressive residual stress(CRS).Finally,fatigue tests of the specimens before and after SAWJP treatment with different process parameters were carried out at room *** results highlighted that the fatigue life of the TA19 specimen can be increased by 5.46,5.98,and 6.28 times under relatively optimal process parameters,which is mainly due to the improved surface integrity of the specimen after SAWJP ***,the fatigue life of specimens treated with improper process parameters is decreased by 0.55 to 0.69 times owing to the terrible surface roughness caused by the material *** work verifies that SAWJP can effectively improve the surface integrity and fatigue life of workpieces,and reveals the relationship between process parameters,surface integrity,and fatigue life,which provides support for the promotion of SAWJP in the manufacturing fields.

关键词： Fatigue testing Process parameters Submerged abrasive waterjet peening Surface integrity Surface treatment Titanium alloy TA19

Intelligent Diagnosis Method for Typical Co-frequency Vibration Faults of Rotating Machinery Based on SAE and Ensembled ResNet-SVM

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Chinese Journal of Mechanical Engineering 2024年第4期 228-243页

作者： xiancheng zhang Xin Pan Hao Zeng Haofu Zhou Beijing Key Laboratoryof Health Monitoring and Self-recovery for High-end Mechanical Equipment Beijing University of Chemical Technology Engineering Research Center of Chemical Safety (Ministry of Education) Beijing University of Chemical Technology Engineering Management Department of China Three Gorges New Energy (Group) Co. Ltd.

Intelligent fault diagnosis is an important method in rotating machinery fault diagnosis and equipment health management. To deal with co-frequency vibration faults, a type of typical fault in rotating machinery, this paper proposes a fault diagnosis method based on the stacked autoencoder(SAE) and ensembled ResNet-SVM. Furthermore, the time-and frequency-domain features of several co-frequency vibration faults are summarized based on the mechanism analysis and calculated using actual vibration data. To realize and validate the high-precision diagnosis method of rotating equipment with co-frequency faults proposed in this study, the following three criteria are required: First, to improve the effectiveness and robustness of the ensembled model and the sliding window using data augmentation, adding noise, autoencoder(AE) and SAE methods are analyzed in terms of principle and practical effects. Second, ResNet is used as the feature extractor for the ensembled ResNet-SVM model. Feature extraction is carried out twice, and the extracted co-frequency fault features are more comprehensive. Finally, the data augmentation method and ensemble ResNet-SVM are combined for fault diagnosis and compared with other methods. The experimental results show that the accuracy of the proposed method can exceed 99.9%.

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GH4169高温合金孔结构的多级凸包旋转冷扩孔挤压强化工艺参数优化

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航空学报 2024年第16期45卷 282-293页

作者：李洪伟雷学林张成成汤超宗康胜龙陈亚龙程吕一张显程华东理工大学承压系统与安全教育部重点实验室上海200237 中国航发商用航空发动机有限责任公司上海201100

提出了一种高温合金含孔结构的新型冷挤压强化工艺,即多级凸包旋转冷扩孔挤压工艺(MCR-CEP),以提升镍基高温合金孔结构件疲劳寿命。为了最大程度地提升MCR-CEP工艺的强化效果,通过多次挤压强化试验,探究凸包间距、主轴转速和挤压量3类... 详细信息

提出了一种高温合金含孔结构的新型冷挤压强化工艺,即多级凸包旋转冷扩孔挤压工艺(MCR-CEP),以提升镍基高温合金孔结构件疲劳寿命。为了最大程度地提升MCR-CEP工艺的强化效果,通过多次挤压强化试验,探究凸包间距、主轴转速和挤压量3类工艺参量对强化后孔内壁表面完整性的影响规律。试验结果表明:凸包间距和主轴转速越大,加工过程的挤压力越小;较大的挤压量易造成孔内壁粗糙度增加和残余应力饱和。综合考虑加工过程挤压力、显微硬度、表面粗糙度和残余应力情况,初步确定最优挤压参数为挤压工具凸包间距0.8 mm、主轴转速100 r/min、挤压量0.2 mm。随后,通过疲劳试验对优化工艺的强化效果进行验证。结果显示:与未强化孔结构相比,MCR-CEP强化试样的平均疲劳寿命提升至少118%,最优工艺参数加工的试样疲劳寿命提升达173%。

关键词：孔挤压强化表面完整性 GH4169 正交试验疲劳寿命

镍基高温合金深小孔的旋转冷挤压强化工艺优化

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机械工程材料 2024年第1期48卷 46-52页

作者：张卿雷学林郭海龙何岑垚张显程华东理工大学机械与动力工程学院上海200237 中国航发湖南动力机械研究所株洲412000

采用多级凸包硬质合金挤压工具对镍基高温合金平板中的深小孔进行旋转冷挤压及无旋转冷挤压(主轴转速为0)试验,研究了挤压率(2.4%,3.0%,3.6%)与主轴转速(0,66,200 r·min^(-1))对孔壁表面完整性及试样疲劳寿命的影响,确定了旋转冷挤压... 详细信息

采用多级凸包硬质合金挤压工具对镍基高温合金平板中的深小孔进行旋转冷挤压及无旋转冷挤压(主轴转速为0)试验,研究了挤压率(2.4%,3.0%,3.6%)与主轴转速(0,66,200 r·min^(-1))对孔壁表面完整性及试样疲劳寿命的影响,确定了旋转冷挤压优化工艺。结果表明:与无旋转冷挤压强化工艺相比,旋转冷挤压强化后孔壁表面微裂纹较少,随着主轴转速的增加,微裂纹增多,表面粗糙增大,且相同主轴转速下,挤压率越大,粗糙度越小,表面硬度越高,残余压应力和压应力层厚度越大。优化旋转冷挤压工艺参数为主轴转速66 r·min^(-1)、挤压率3.0%,该工艺下的孔壁表面微裂纹少,塑性变形层较厚(约30μm),表层硬度提升(硬度峰值为515 HV),表面粗糙度较低(Ra为0.298μm),沿深度方向形成了厚度约为450μm、应力峰值为498 MPa的周向残余压应力层;在优化工艺下孔强化后试样的疲劳寿命约为未强化试样的6.6倍,疲劳裂纹源由孔壁表面向内部偏移了约45μm。

关键词：镍基高温合金深小孔旋转冷挤压表面完整性疲劳性能

Active and passive compliant force control of ultrasonic surface rolling process on a curved surface

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Chinese Journal of Aeronautics 2022年第7期35卷 289-299页

作者： Kaiming zhang Ji WANG Yixin LIU Shuang LIU xiancheng zhang School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

Ultrasonic surface rolling process(USRP)is one of the effective mechanical surface enhancement *** the USRP,unstable static force will easily do harm to the surface *** order to achieve a higher surface quality on the part with a curved surface,an active and passive compliant USRP system has been *** compliant USRP tool can produce the natural obedience deformation along the part *** control based on the fuzzy Proportional-integral-derivative(PID)method is then designed to maintain the static force during the *** have been performed on a real aero-engine blade with curved *** is proved that the deigned active and passive compliant USRP system can significantly reduce the force variation from 42.2 N to 4.2 N,and achieve a uniform surface quality after processing.

关键词： Active and passive compliant Curved surface Force control Surface integrity Ultrasonic surface rolling process

Achieving High Strength-plasticity of Nanoscale Lamellar Grain Extracted from Gradient Lamellar Nickel

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 67-78页

作者： Zimeng Wang Yunfei Jia Yong zhang Pei Tang xiancheng zhang Shantung Tu Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China

Traditional metallic materials usually face a dilemma between high strength and poor strain hardening ***,heterogeneous structured metallic materials have been found to obviously overcome the ***,gradient lamellar structure was fabricated through ultrasound-aided deep rolling technique in pure Ni with high stacking fault energy after heat *** gradient lamellar Ni was successively divided into the four ***-situ micropillar compression tests were conducted in diferent regions to reveal the corresponding microscopic mechanical *** characterization techniques were performed to explore underlying deformation mechanisms and the efects of microstructural parameters on deformation *** work demonstrates that the micropillar with near nanoscale lamellar thickness possesses excellent strength and *** one hand,the reason for high strength of near nanoscale micropillar is that the strength of micropillar increases with the decrease of lamellar thickness according to the Hall-Petch *** the other hand,numerous lamellar grain boundaries perpendicular to the loading direction is found to hinder the motion of slip bands,resulting in great strain hardening capacity in the near nanoscale lamellar micropillar.

关键词： Nanoscale lamellar structure Compression test Slip Dislocation

Creep life assessment of aero-engine recuperator based on continuum damage mechanics approach

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Frontiers of Mechanical Engineering 2022年第4期17卷 273-284页

作者： Pengpeng LIAO Yucai zhang Guoyan ZHOU xiancheng zhang Wenchun JIANG Shantung TU Key Laboratory of Pressurized System and Safety MOESchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Heavy Oil Processing College of Chemical EngineeringChina University of Petroleum(East China)Qingdao 266555China

The creep life of an aeroengine recuperator is investigated in terms of continuum damage mechanics by using finite element *** effects of the manifold wall thickness and creep properties of brazing filler metal on the operating life of the recuperator are *** show that the crack initiates from the brazing filler metal located on the outer surface of the manifold with the wall thickness of 2 mm and propagates throughout the whole region of the brazing filler metal when the creep time reaches 34900 *** creep life of the recuperator meets the requirement of 40000 h continuous operation when the wall thickness increases to 3.5 mm,but its total weight increases by 15%.Decreasing the minimum creep strain rate with the enhancement of the creep strength of the brazing filler metal presents an obvious effect on the creep life of the *** the same stress level,the creep rupture time of the recuperator is enhanced by 13 times if the mismatch between the minimum creep rate of the filler and base metal is reduced by 20%.

关键词： creep life assessment brazed joint continuum damage mechanics aeroengine recuperator

基于LSTM的半航空瞬变电磁资料去噪方法研究

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物探化探计算技术 2024年第4期46卷 423-433页

作者：张先承毛立峰杨逸周子钧成都理工大学地球勘探与信息技术教育部重点实验室成都610059

随着干扰电磁环境的因素越来越多,半航空瞬变电磁数据所含噪声的特性难以正确地处理和分析,而去噪是提高瞬变电磁场信号处理和分析精度的重要手段之一。相较于传统的去噪方法大都依赖频率特征、耗时较长以及计算参数难以确定,LSTM(Long ... 详细信息

随着干扰电磁环境的因素越来越多,半航空瞬变电磁数据所含噪声的特性难以正确地处理和分析,而去噪是提高瞬变电磁场信号处理和分析精度的重要手段之一。相较于传统的去噪方法大都依赖频率特征、耗时较长以及计算参数难以确定,LSTM(Long Short-Term Memory)神经网络不依赖频率特征的同时能够很好地处理非线性时间序列。因此笔者将LSTM应用于半航空瞬变电磁数据处理,在一维正演数据添加各类噪声的基础上,分为训练和测试,训练采用监督学习方式进行,从而捕获信号的特征和结构信息,测试阶段也采用监督学习方式进行,利用有标签训练数据对网络进行优化进一步提高去噪效果。最后将测试效果良好的模型应用于实际资料中,结果表明此方法能够有效地去除晚期道中的噪声,是一种能够用于半航空瞬变电磁数据去噪的可行手段。

关键词： LSTM网络半航空瞬变电磁去噪训练测试

Integration of interlayer surface enhancement technologies into metal additive manufacturing:A review

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Journal of Materials Science & Technology 2023年第34期165卷 94-122页

作者： Yufei Chen xiancheng zhang Donghong Ding Xiaowei Wang Kaiming zhang Yixin Liu Tiwen Lu Shantung Tu Key Laboratory of Pressure Systems and Safety Ministry of EducationEast China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China Institute of Reliability Centered Manufacturing Nanjing Tech UniversityNanjing 211816China Jiangsu Key Lab of Design and Manufacture of Extreme Pressure Equipment Nanjing 211816China College of Materials Shanghai Dianji UniversityShanghai 201306China

Additive manufacturing(AM)has the advantages of rapid prototyping,high design freedom,and flexible manufacturing,while the mechanical properties of additively manufactured products are not uniform due to inherent defects and residual *** of interlayer surface enhancement(SE)technologies into AM is a potential solution to improve the microstructure,close defects,residual stress state,mechanical properties,and chemical properties of formed *** paper reviews the current literature on hybrid AM process through the combination of SE and AM,and proves the possibility of integrating SE technologies into AM from the technical *** the improvement effects of SE processes on AM parts are introduced in terms of microstructure,defects,residual stress,mechanical properties,and chemical ***,considering the commonly used directed energy deposition(DED)process and ultrasonic impact treatment(UIT),a closed-loop quality control framework for integration of interlayer UIT into the DED process is *** research directions to the hybrid AM and interlayer SE are pointed out.

关键词： Surface enhancement Additive manufacturing Residual stress Multi-sensor monitoring