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Micro-structure evolution, precipitation behavior and strengthening mechanism of Ni-Cr-Mo system steel fabricated via laser powder bed fusion and subsequent quenching control

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Chinese Journal of Aeronautics 2025年第3期38卷 560-592页

作者： Qing WANG Deyin KONG Shihui ZHOU Xingran LI Zhihui ZHANG The Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun 130025China Weihai Institute for Bionic Jilin UniversityWeihai 264402China State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China

High-performance 24CrNiMo steel was fabricated using Laser Powder Bed Fusion (LPBF). Subsequent quenching treatment was applied and the influence of quenching temperatures on micro-structure evolution and properties was systematically characterised and analysed. The micro-structure of the as-built steel consisted of two parts. The first part comprised martensite with twins combined with ω-Fe nano-particles, and the second part consisted of lower bainite in the molten pool, as well as upper bainite, granular bainite and tempered martensite in the heat-affected zone. With the quenching temperatures varying from 800℃ to 950℃, the micro-structure gradually transformed from acicular ferrite + martensite to tempered martensite +θ-Fe3C carbides, and the grain size exhibited noticeable growth. Moreover, quenching treatments could eliminate the anisotropy and inhomogeneity of the micro-structure. The rod-shaped nanosized η-Fe2C and θ-Fe3C precipitates were clearly observed, which were converted from ω-Fe and distributed at multiple angles in the lath. The size and number of nano-precipitates, triggered by the high self-tempering degree of martensite, gradually increased. The relationships among grain size, the twins, dislocation density and nano-precipitation and the dramatically improved performance of quenched samples were analysed using strengthening mechanisms. After quenching at 850℃, the as-built 24CrNiMo steel attained ultra-high mechanical properties including hardness, Ultimate Tensile Strength (UTS), Elongation (El) and impact energy with values of 480.9 HV_(1), 1611.4 MPa, 9.8% and 42.8 J, respectively. Meanwhile, both the wear and thermal fatigue resistance increased by approximately 40%. This study demonstrated that LPBF-fabricated 24CrNiMo steel, with matching good performances, can be achieved using a subsequent one-step quenching process.

关键词： Laser powder bed fusion 24CrNIMo steel Quenching control Micro-structure evolution Precipitate Comprehensive properties Strengthening mechanisms

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Investigation on the Mechanical Properties and Shape Memory Effect of Landing Buffer Structure Based on Ni Ti Alloy Printing

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Chinese Journal of Mechanical engineering 2023年第4期36卷 415-424页

作者： Zhenglei Yu Renlong Xin Zezhou Xu Yining Zhu Xiaolong Zhang Shijie Hao Zhihui Zhang Ping Liang State Key Laboratory of Automotive Simulation and Control Jilin University Key Lab of Bionic Engineering Ministry of Education Jilin University Agriculture College Yanbian University State Key Laboratory of Heavy Oil Processing China University of Petroleum

With the deepening of human research on deep space exploration, our research on the soft landing methods of landers has gradually deepened. Adding a buffer and energy-absorbing structure to the leg structure of the lander has become an effective design solution. Based on the energy-absorbing structure of the leg of the interstellar lander, this paper studies the appearance characteristics of the predatory feet of the Odontodactylus scyllarus. The predatory feet of the Odontodactylus scyllarus can not only hit the prey highly when preying, but also can easily withstand the huge counter-impact force. The predatory feet structure of the Odontodactylus scyllarus, like a symmetrical cone, shows excellent rigidity and energy absorption capacity. Inspired by this discovery, we used SLM technology to design and manufacture two nickel-titanium samples, which respectively show high elasticity, shape memory, and get better energy absorption capacity. This research provides an effective way to design and manufacture highmechanical energy-absorbing buffer structures using bionic 3D printing technology and nickel-titanium alloys.

关键词： bionic protective structure Odontodactylus scyllarus NiTi alloy 3D printing Numerical simulation Recoverability

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Experimental Study on Impingement Processes of Fuel Sprays on Biomimetic Structured Surfaces

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Journal of bionic engineering 2024年第1期21卷 362-373页

作者： Yanling Chen Liang Guo Wanchen Sun Yuying Yan Rong Xuan Junfeng Zhang State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China Faculty of Engineering University of NottinghamNottingham NG72RDUK

To improve the controllability of the wall-wetting process after the fuel spray-wall impingement in internal combustion engines,the methods of laser etching,chemical etching and surface free energy modification are used to prepare biomimetic structured surfaces with different *** impingement processes of diesel and n-butanol sprays on the walls under different conditions are experimentally *** the surface oleophilicity increases,the spreading radius of wall-impinging sprays *** about 5 s after the fuel injections,the fuel spray droplets hit the walls for the first time,and the secondary breakup and rebound *** mixture concentrations of different fuels hitting the various walls reach the peak *** a higher surface temperature,the peak value of the mixture concentration is mainly related to the heat flux to the fuel droplets in different boiling regimes from the metal *** concentration of the air–fuel mixture in the near wall region increases with increasing surface oleophilicity,increasing wall temperature and decreasing ambient *** with diesel,n-butanol presents a higher air–fuel mixture concentration in the near wall region.

关键词： Spray-wall impingement Morphological development Air-fuel mixture concentration Surface wettability Wall temperature:Ambient pressure

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Effect of Cutting Trailing Edge Serration on Aerodynamic Noise of Airfoil 6th

Effect of Cutting Trailing Edge Serration on Aerodynamic Noi...

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6th Symposium on Fluid-Structure-Sound Interactions and control, FSSIC 2023

作者： Zhang, Zhe Chen, Tao Zhang, Yingchao Shen, Chun Zhang, Chengchun State Key Laboratory of Automotive Simulation and Control Jilin University Changchun130022 China Key Laboratory of Bionic Engineering Ministory of Education Jilin University Changchun130022 China

ISBN: (纸本)9789819762101

This paper investigated the effects of cutting trailing edge serration on airfoil aerodynamic noise based on the acoustic analogy method. Large eddy simulation (LES) was used to capture the transient near-field information of the airfoil, and the Ffowcs Williams Hawkings (FW-H) equation is employed to predict the far-field noise. The research subject is the NACA0012 airfoil, with the length and width of serration ranging from 0.01 to 0.03 and 0.02 to 0.04 times the airfoil chord length (c), respectively. Acoustic experimental data are used to validate the accuracy of the simulation method. The angle of attack of incoming flow is 0°, with Reynolds and Mach numbers of 6.6 × 106 and 0.147, respectively. The research indicates that within the specified parameter range, the noise reduction effect of the serration perpendicular to the incoming flow direction is proportional to both the height and width of the serration. The maximum noise reduction is 3.3 dB. The cutting trailing edge serration leads to an increase in the high-frequency component of the streamwise noise. In the presence of cutting trailing edge serration, the overall sound pressure level of the streamwise noise increases. Compared to embedded trailing edge serration, cutting trailing edge serration have a lower limited height in terms of noise reduction. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Noise abatement

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Mechanical Characteristics Analysis of 3D-printing Novel Chiral Honeycomb Array Structures Based on Functional Principle and Constitutive Relationship

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Journal of bionic engineering 2023年第5期20卷 1917-1929页

作者： Ruiyao Liu Guofeng Yao Zezhou Xu Xue Guo Jianyong Li Zhenglei Yu Ping Liang Zhihui Zhang Chunyang Han Department of Mechanics School of Mechanical and Aerospace EngineeringJilin UniversityChangchun130022China Key Laboratory of Bionic Engineering of Ministry of Education Jilin UniversityChangchun130022China State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun130022China Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun130022China

Four novel chiral honeycomb structures inspired by the biological arrangement shape are *** functional principle is raised to solve the large deformation of bio-inspired structures and the structural constitutive model is proposed to explain the quasi-static mechanical properties of chiral honeycomb array structures and honeycomb *** and experiment results verify the accuracy of theoretical analysis results and the errors are all within 15%.In structural mechanical properties,Equidimensional Chiral Honeycomb Array Structure(ECHS)has excellent mechanical *** ECHS,Small-sized Column Chiral Honeycomb Array Structure(SCHCS)has the best *** bearing capacity,specific energy absorption,and specific strength of SCHCS are more than twice as much as the others in this *** chiral honeycomb array structure has the best mechanical properties at a certain *** the structural design,the optimal size model should be obtained first in combination with the optimization algorithm for the protection design.

关键词： bionic Gradient sizes Function principle Constitutive model The global simulated annealing optimization algorithm

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Effect of Multiple Models of Closed-loop Transfer Functions on Inter-harmonic Oscillation Characteristics of Grid-connected PMSG

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1955-1964页

作者： Jingyi Li Jianjun Yang Xiaorong Xie Haozhi Li Ke Wang Zhaohui Shi Key Laboratory of Far-shore Wind Power Technology of Zhejiang Province Huadong Engineering Corporation LimitedPower ChinaHangzhou 310014China. State Key Lab of Control and Simulation of Power Systems and Generation Equipment(Dept.of Electrical Engineering Tsinghua University)Beijing 100084China.

Establishing a suitable closed-loop transfer function model for the grid-connected PMSG system is the key basis in performing inter-harmonic characteristics *** closed-loop transfer functions can be constructed when different components of the converter controller are taken into ***,the effect of different components of the converter controller on inter-harmonic stability analysis is not *** this paper,the complete transfer function,considering different loops,is first *** on the complete closed-loop transfer function,the DC-link,PLL and voltage forward-feed are removed step by step to derive different closed-loop transfer *** inter-harmonic related poles of different closed-loop transfer functions are further calculated to analyze the effect of closedloop transfer functions on inter-harmonic characteristics ***,by performing time domain simulation,the correctness of the theoretical analysis results is *** results show that under the conditions of a weak AC system,each loop of the converter control system will reduce the stability of the interharmonic in the sub-synchronous frequency range and influence the inter-harmonic oscillation *** transfer function needs to consider the influence of each loop to accurately calculate the inter-harmonic stability of the system.

关键词： Closed-loop transfer function converter controller inter-harmonic characteristics PMSG

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Evaporation Characteristics and Morphological Evolutions of Fuel Droplets After Hitting Different Wettability Surfaces

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Journal of bionic engineering 2023年第2期20卷 734-747页

作者： Yanling Chen Liang Guo Ningning Cai Wanchen Sun Yuying Yan Degang Li Han Wang Rong Xuan State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130025China School of Business and Management Jilin UniversityChangchun130012China Faculty of Engineering University of NottinghamNottinghamNG72RDUK

To solve the wall-wetting problem in internal combustion engines,the physical and chemical etching methods are used to prepare different wettability surfaces with various *** evaporation characteristics and morphological evolution processes of diesel and n-butanol droplets after hitting the various surfaces are *** results show that the surface microstructures increase the surface roughness(Ra),enhancing the oleophilic property of the oleophilic *** with n-butanol droplets,the same surface shows stronger oleophobicity to diesel *** a droplet hits an oleophilic property surface with a lower temperature,the stronger the oleophilicity,the shorter the evaporation *** oleophilic surfaces,larger Ra leads to a higher Leidenfrost temperature(TLeid).The low TLeid caused by enhanced oleophobicity,dense microstructures and increased convex dome height facilitates droplet rebound and promotes the evaporation of the wall-impinging droplets into the *** evaporation rate of the droplets is not only related to the characteristics of the solid surfaces and the fuel droplets but also affected by the heat transfer rate to the droplets in different boiling *** spreading diameter of a droplet on an oleophobic surface varies significantly less with time than that on an oleophilic surface under the same surface temperature.

关键词： Fuel droplets Wettability Evaporation time Leidenfrost temperature Morphological evolutions

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Adhesion and corrosion resistance of polycaprolactone coating on NiTi alloy surface after alkali heat pretreatment

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Biosurface and Biotribology 2022年第4期8卷 307-314页

作者： Zhihui Zhang Yanan Yang Yunting Guo Pengwei Sha Zezhou Xu Zhenglei Yu Jiashun Si Zhengao Zhang Jia Guo Yifan Chen Key Laboratory of Bionic Engineering Ministry of EducationJilin UniversityChangchunChina Weihai Institute for Bionic Jilin UniversityWeihaiChina State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchunChina Beijing Reserarch Institute of Automation for Machinery Industry Co. LtdBeijingChina Key Laboratory of Automobile Materials Ministry of EducationCollege of Materials Science and EngineeringJilin UniversityChangchunChina

Selective laser melting of nickel-titanium alloy(SLM-NiTi)can precisely control the size of the sample molding structure and has attracted extensive attention due to its special superelasticity and shape memory ***,the biological inertness and poor corrosion resistance of SLM-NiTi alloy limit their wide application as biomedical implant *** this study,polycaprolactone(PCL)coating was prepared on SLM-NiTi alloy by dipping and pulling method,and the effects of alkali heat pretreatment on the morphology,adhesion,corrosion resistance,long-term stability and biomineralisation of the PCL coatings were *** results showed that PCL coating can substan-tially improve the performance of SLM-NiTi alloy,and the PCL coating after alkali heat pretreatment has higher adhesion(increased from 1,747 to 2,498 mN)and lower corrosion current density(reduced by about an order of magnitude compared to PCL coating alone).In addition,the necessary stability,biomineralisation and biocompatibility ability of coatings were also further ***,the alkali heat pretreated PCL-coated SLM-NiTi alloy has good application prospects in implants due to its superior properties.

关键词： adhesion alkali heat pretreatment corrosion resistance PCL coating SLM-NiTi alloy

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A novel electro-Fenton hybrid system for enhancing the interception of volatile organic compounds in membrane distillation desalination

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Journal of Environmental Sciences 2024年第4期138卷 189-199页

作者： Hongxin Liu Kuiling Li Kunpeng Wang Zhiyong Wang Zimou Liu Sichao Zhu Dan Qu Yu Zhang Jun Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua UniversityBeijing 100084China School of Chemical and Environmental Engineering Beijing CampusChina University of Mining and TechnologyBeijing 100083China Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China

Membrane distillation(MD)is a promising alternative desalination technology,but the hydrophobic membrane cannot intercept volatile organic compounds(VOCs),resulting in aggravation in the quality of *** term of this,electro-Fenton(EF)was coupled with sweeping gas membrane distillation(SGMD)in a more efficient way to construct an advanced oxidation barrier at the gas-liquid interface,so that the VOCs could be trapped in this layer to guarantee the water quality of the *** the so-called EF-MD process,an interfacial interception barrier containing hydroxyl radical formed on the hydrophobic membrane *** contributed to the high phenol rejection of 90.2% with the permeate phenol concentration lower than 1.50 mg/*** interceptions can be achieved in a wide temperature range,even though the permeate flux of phenol was also *** EF-MD system was robust to high salinity and could electrochemically regenerate ferrous ions,which endowed the long-term stability of the *** novel EF-MD configuration proposed a valuable strategy to intercept VOCs in MD and will broaden the application of MD in hypersaline wastewater treatment.

关键词： Membrane distillation VOC interception Interfacial oxidation Electro-Fenton Hypersaline wastewater

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Pomelo Peel-Inspired 3D-Printed Porous Structure for Efficient Absorption of Compressive Strain Energy

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Journal of bionic engineering 2022年第2期19卷 448-457页

作者： Baisong Yang Wenhui Chen Renlong Xin Xiaohong Zhou Di Tan Chuan Ding You Wu Liang Yin Chuyang Chen Shan Wang Zhenglei Yu Jonathan TPham Sheng Liu Yifeng Lei Longjian Xue School of Power and Mechanical Engineering The Institute of Technological SciencesWuhan UniversitySouth Donghu Road 8Wuhan 430072HubeiChina State Key Laboratory of Automotive Simulation and Control and Key Lab of Bionic Engineering Ministry of EducationJilin UniversityChangchun 130022China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Department of Chemical and Materials Engineering University of KentuckyLexingtonKY 40506USA

The porous structure in pomelo peel is believed to be responsible for the protection of its fruit from damage during the free falling from a *** quantitative understanding of the relationship between the deformation behavior and the porous structure could pave the way for the design of porous structures for efficient energy ***,a universal feature of pore distribution in pomelo peels along the radial direction is extracted from three varieties of pomelos,which shows strong correlation to the deformation behavior of the peels under *** by the porous design found in pomelo peels,porous polyether-ether-ketone(PEEK)cube is additively manufactured and possesses the highest ability to absorb energy during compression as compared to the non-pomelo-inspired geometries,which is further confirmed by the finite element *** nature-optimized porous structure revealed here could guide the design of lightweight and high-energy-dissipating materials/devices.

关键词： bionic design Pomelo peel Porous structure 3D printing Energy absorption

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