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Chinese Journal of Aeronautics 2022年第11期35卷 401-415页

作者： Shanyue GUAN Xiaokai WANG Lin HUA Yixuan LI hubei Key Laboratory of Advanced technology for automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China School of automotive Engineering Wuhan University of TechnologyWuhan 430070China

The aeroengine casing ring forgings have complex cross-section shapes,when the conventional ultrasonic or phased array is applied to detect such curved surfaces,the inspection images always have low resolution and even artifacts due to the distortion of the wave beam.In this article,taking a type of aeroengine casing ring forging as an example,the Total Focusing Method(TFM)algorithms for curved surfaces are investigated.First,the Acoustic Field Threshold Segmentation(AFTS)algorithm is proposed to reduce background noise and data calculation.Furthermore,the Vector Coherence Factor(VCF)is adopted to improve the lateral resolution of the TFM imaging.Finally,a series of 0.8 mm diameter Side-Drilled Holes(SDHs)are machined below convex and concave surfaces of the specimen.The quantitative comparison of the detection images using the conventional TFM,AFTS-TFM,VCF-TFM,and AFTS-VCF-TFM is implemented in terms of data volume,imaging Signal-to-Noise Ratio(SNR),and defect echo width.The results show that compared with conventional TFM,the data volume of AFTS-VCF-TFM algorithm for convex and concave is decreased by 32.39%and 73.40%,respectively.Moreover,the average SNR of the AFTS-VCF-TFM is gained up to 40.0 dB,while the average 6 dB-drop echo width of defects is reduced to 0.74 mm.

关键词： Aeroengine casing Acoustic Field Threshold Segmentation(AFTS) Curved surfaces Total Focusing Method(TFM) Vector Coherence Factor(VCF)

An innovation of Evaluation and Design of Vehicle Acceleration Sound Based on EEG Signals

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Journal of Bionic Engineering 2024年第1期21卷 344-361页

作者： Liping Xie XinYou Lin Wan Chen Zhien Liu Yawei Zhu College of Mechanical Engineering&Automation Fuzhou UniversityFuzhou 350108China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China

There is a bottleneck in the design of vehicle sound that the subjective perception of sound quality that combines multiple psychological factors fails to be accurately and objectively quantified.Therefore,EEG signals are introduced in this paper to investigate the evaluation and design method of vehicle acceleration sound with powerful sound quality.Firstly,the experiment of EEG acquisition and subjective evaluation under the stimulation of powerful vehicle sounds is conducted,respectively,then three physiological EEG features of PSD_β,PSD_γand DE are constructed to evaluate the vehicle sounds based on the correlation analysis algorithms.Subsequently,the Adaptive Genetic Algorithm(AGA)is proposed to optimize the Elman model,where an intelligent model(AGA–Elman)is constructed to objectively predicate the perception of subjects for the vehicle sounds with powerful sound quality.The results demonstrate that the error of the constructed AGA–Elman model is only 2.88%,which outperforms than the traditional BP and Elman model;Finally,two vehicle acceleration sounds(Design1 and Design2)are designed based on the constructed AGA–Elman model from the perspective of order modulation and frequency modulation,which provide the acoustic theoretical guidance for the design of vehicle sound incorporating the EEG signals.

关键词： EEG signal Brain activity analysis Vehicle sound design Adaptive genetic algorithm-Elman model

Research on Measurement Method of Muffler Performance under High Temperature and High-Speed Airflow Conditions

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Journal of Beijing Institute of technology 2020年第2期29卷 241-250页

作者： Liping Xie Chihua Lu Zhien Liu Yawei Zhu hubei Key Laboratory of Advanced technology of automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Ignoring the influence of flow velocity and flow temperature on muffling performance,performance tests were conducted without airflow in the development phase of the muffler which accounts to the difficulty of obtaining a perfect match between the actual noise reduction effect and the design goal.Based on the two-load test theory,a set of high-temperature and high-speed airflow simulation measurement devices for the muffler has been built.In order to avoid the impact of high-temperature and high-speed airflow on the sensor,a high temperature resistant sensor holder has been designed for the test rig.The sound pressure has been measured in the pipe by using the lead-out measurement.In addition,a variable impedance load is placed at the end of the test tube to realize the switch between two different impedance loads by the wave handle of the variable impedance load.A sound source correction method is proposed to decrease the random fluctuation of the spectral characteristics of the output noise signal,which is caused by the acoustic impedance variation at the connection between the transition pipeline and the combined sound source system.Finally,an acoustic software has been used to calculate the transmission loss of the muffler in the presence of high temperature airflow.In comparing the experimental measurements and the simulation results,the small difference shows that:the bench not only can effectively simulate high-temperature and flow velocity environment of the engine but also accurately test the transmission loss of the muffler.

关键词： muffler lead-out measurement variable load source correction transmission loss

Effects of Electric and Magnetic Treatments on Microstructures of Solid Metals: A Review

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 1-21页

作者： Yanli Song Wenlin Wu Yongqing Yu Lin Hua hubei Key Laboratory of Advanced technology for automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China School of automotive Engineering Wuhan University of TechnologyWuhan 430070China hubei Research center for New Energy&Intelligent Connected Vehicle Wuhan University of TechnologyWuhan 430070China

An external electric or magnetic field can transfer high-intensity energy directly to the electronic scale of materials,and change the spin,energy level arrangement and trajectory of electrons.These changes produce tremendous and profound impacts on the microstructure and mechanical properties of metal materials,which may be impos-sible with traditional technologies.This paper reviews the effects of electric or magnetic field on the microstruc-tures of solid metals including phase transformation,precipitation,recrystallization,dislocations and so on.Based on the existing research results,the mechanisms of these effects have been discussed.Additionally,some typical applications of electric and magnetic treatments on solid metals have been described and the challenges in this field have also been discussed.

关键词： Electric field Magnetic field Microstructures Mechanical properties Solid metals

连续移动局部感应熔覆过程中的温度场演变和热量传递

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Journal of Central South University 2020年第5期27卷 1572-1586页

作者：刘思宇秦训鹏张进朋詹军 hubei Key Laboratory of Advanced technology for automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China hubei Sanhuan Intelligent technology Co. Ltd.Wuhan 430074China

本文研究了连续运动感应熔覆层的温度场演变和热影响区的深度,建立了点式连续移动感应熔覆的三维有限元模型以研究固定和移动感应熔覆模型的温度分布,设计了一种适用于曲面熔覆的新感应器,通过温度测量验证了模型的可靠性。研究了工艺... 详细信息

本文研究了连续运动感应熔覆层的温度场演变和热影响区的深度,建立了点式连续移动感应熔覆的三维有限元模型以研究固定和移动感应熔覆模型的温度分布,设计了一种适用于曲面熔覆的新感应器,通过温度测量验证了模型的可靠性。研究了工艺参数对最高温度的影响和热量的产生与传递。对熔化速率进行了定量计算来验证温度的分布和显微组织的关系。结果表明,熔覆层与基体之间可形成良好的冶金结合,从熔覆层顶部到基体熔化速率逐渐降低,基体中的晶粒尺寸逐渐增大。与整体加热相比,连续移动局部感应熔覆热影响区相对较小。

关键词：型面修复连续移动感应熔覆温度场演变热量传递

Preparation and Composition Distribution in Hollow Tubular TiB-Ti Composites during Centrifugal Spraying Process

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Journal of Wuhan University of technology(Materials Science) 2022年第3期37卷 518-524页

作者：张仲仁 DU Runkun ZHANG Fan ZHANG Jinyong 雷丽文王伟 School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China School of automotive Engineering Wuhan University of TechnologyWuhan 430070China hubei Key Laboratory of Advanced technology for automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China

The hollow cylinders of TiB-Ti composites with a gradient distribution of Ti phase were synthesized by the combination of traditional slurry spray with centrifugal forming process.The influences of the concentration of sodium hexametaphosphate(SHMP),the concentration of polyvinyl alcohol(PVA)and solid content(20 vol%-35 vol%)on the rheological properties of the TiB_(2)-Ti composite slurries were investigated.Slurries with low viscosity,weak thixotropy and shear-thinning behaviour were obtained for facilitating the slurry spraying process.The effects of different centrifugal conditions on the migration of components during the forming process were studied.The phase composition and the elements distribution of the prepared samples were characterized by the energy-dispersive X-ray spectrometer.The observations revealed that the samples fabricated at 1500 r/min for 3 min had a significant composition variation.For two-phase systems with small density differences and large particle size variation,centrifugal time was more important than centrifugal speed in forming a continuous gradient structure.

关键词： hollow tubular TiB-Ti composites centrifugal spraying process rheological properties composition distribution

Tribological Performance Improvement of Bearing Steel GCr15 by an Alternating Magnetic Treatment

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Acta Metallurgica Sinica(English Letters) 2017年第10期30卷 957-964页

作者： Yan-Li Song Cheng Yu Xia Miao Xing-Hui Han Dong-Sheng Qian Xu Chen hubei Key Laboratory of Advanced technology of automotive Parts Wuhan University of Technology Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of Technology School of Materials Science and Engineering Wuhan University of Technology

This paper discusses the tribological performance of the bearing steel GCr15 treated by an alternating magnetic field. The wear test results showed that the average of wear mass losses decreased by nearly 80% after the magnetic treatment, compared to those before the magnetic treatment. The micro-hardness and microstructures（i.e., grain size,carbide morphology and dislocation distribution） before and after the magnetic treatment were experimentally investigated,and the mechanism of the tribological performance improvement of the bearing steel GCr15 due to the magnetic treatment was then revealed based on the above results.

关键词： Tribological performance Magnetic treatment Bearing steel

The Effect of Nd^(3+) Concentration on Upconversion Luminescence in Yb^(3+)/Tm^(3+)/Nd^(3+) Tripledoped b-NaGdF_(4) Nanocrystals

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Journal of Wuhan University of technology(Materials Science) 2022年第3期37卷 393-398页

作者：侯华羽 GAN Lin 王友法王伟 State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of automotive Engineering Wuhan University of TechnologyWuhan 430070China hubei Key Laboratory of Advanced technology for automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China

Nd^(3+)-doped NaGdF_(4):Yb,Tm nanocrystals were synthesized by an improved high-temperature thermal decomposition method,and the effects of doping concentrations on the crystal structure,phase composition,and upconverted fluorescence intensity were also investigated.The results reveal that the introduction of Nd^(3+) ions does not cause the transformation of the crystal phase,but induce the change of the unit cell parameters.Meanwhile,the fluorescence intensity of the synthesized nanocrystals when co-doped with 3 mol%Nd^(3+) is the strongest under the excitation of 980 nm laser,which is 3.9 times that of the Nd^(3+)-free doped nanoparticles,and the average size is 62.9 nm.And it is located in the blue area of the CIE coordinate diagram,and the corresponding color purity is 91.81%under the same experimental conditions.The resulting nanocrystals show the potential as excellent fluorescence labeling and in vivo imaging probes.

关键词： upconversion Nd^(3+)doped fluorescence intensity β-NaGdF4

A model for converting thermal analysis to volume fraction of high carbon bearing steels during low-temperature tempering

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Journal of Materials Science & technology 2023年第5期136卷 212-222页

作者： Qinglong Liu Junyu Tian Wenting Wei The State Key Laboratory of Refractories and Metallurgy The Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of EducationWuhan University of Science and TechnologyWuhan 430081China School of automotive Engineering Wuhan University of TechnologyWuhan 430070China hubei Key Laboratory of Advanced technology for automotive components(Wuhan University of technology) Wuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070China

Quantitative prediction of phase content is of great importance to control and optimize the heat treat-ment process of steels.In this work,a model for predicting the phase content of tempered high carbon steels was proposed by taking a martensitic 100Cr6 bearing steel as a model case.The microstructural transformations during tempering were studied using thermal analysis,transmission electron microscopy(TEM),and X-ray diffraction(XRD).Kinetics analysis of thermal evolution by employing the isoconver-sional method,and assisted by TEM and XRD characterization,were performed to quantitatively estimate the volume fractions of different phases after tempering.A series of isothermal tempering experiments were designed to verify the model.The predicted results were in good agreement with the experimental results of XRD and electrolytic extraction measurements.

关键词： Bearing steel Martensite tempering Retained austenite Thermal analysis Kinetics

Analysis and prediction of surface roughness for robotic belt grinding of complex blade considering coexistence of elastic deformation and varying curvature

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Science China(Technological Sciences) 2021年第5期64卷 957-970页

作者： XU XiaoHu YE SongTao YANG ZeYuan YAN SiJie ZHU DaHu DING Han State Key Laboratory of Digital Manufacturing Equipment and technology Huazhong University of Science and TechnologyWuhan 430074China hubei Key Laboratory of Advanced technology for automotive components Wuhan University of TechnologyWuhan 430070China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan University of TechnologyWuhan 430070China

Precision prediction of machined surface roughness is challenging facing the robotic belt grinding of complex blade,since this process is accompanied by significant elastic deformation.The resulting poor prediction accuracy,to a great extent,is attributed to the existing prediction model which less considers the dynamics.In this paper,an improved scallop height model is developed to predict and assess the machined surface roughness by taking into account the elastic deformation and the varying curvature of blade,then robotic belt grinding experiments are carried out to evaluate the proposed model from the perspective of surface roughness.Finally factors that influence the scallop height are analyzed,and the suitable empirical equation of surface roughness is proposed to assess and predict the surface quality from the aspect of blade concave and convex surface by adopting the constant scallop height machining.

关键词： robotic belt grinding scallop height elastic deformation surface roughness prediction