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2023 Transactions of the American Nuclear Society Winter Conference and Expo, ANS 2023

作者： Zile, Matthew Van Kauffman, Andrew Herminghuysen, Kevin Li, Shelly Simpson, Michael Kandlakunta, Praneeth Cao, Guoping Cao, Lei R. Nuclear Engineering Program Department of Mechanical and Aerospace Engineering Ohio State University United States Nuclear Reactor Laboratory College of Engineering Ohio State University United States Department of Materials Science and Engineering University of Utah.Idaho National Laboratory United States

The Na-22based radioactive tracer dilution (RTD) technique has been previously demonstrated for mass accounting in small quantities of clean molten salt for bench top testing. While the concept of RTD has proven to be a promising method, it has lacked further validation in large-scale quantities and in fuel-bearing salt. Towards that end, two research initiatives are on-going at The Ohio State University (OSU) and Idaho National Laboratory (INL) to address these challenges. Current work at OSU is focused on evaluating the RTD using the full gamma-ray spectrum of fission products produced by irradiating fuel bearing salt, i.e., UCl3-MgCl2-KCl in a 500-kW research reactor. The INL team has successfully demonstrated the RTD for mass determination using an 8-kg LiCl-KCl-UCl3salt for uranium electrorefining and is currentlyseeking to validate the tracer method with large(about 60 kg)molten salt system(bearing fission products) in an oxide reduction (OR) facility for spent nuclear fuel (SNF) reprocessing. © 2023 American Nuclear Society. All rights reserved.

关键词： Fission products

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Effects of Porosity on Piezoelectric Characteristics of Polyvinylidene Fluoride Films for Biomedical Applications

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Biomedical engineering Frontiers 2023年第1期4卷 92-99页

作者： Jack T.Kloster Matthew J.Danley Victor K.Lai Ping Zhao Advanced Materials Science University of Minnesota-DuluthDuluthMN 55812USA Department of Chemical Engineering University of Minnesota-DuluthDuluthMN 55812USA Department of Mechanical and Industrial Engineering University of Minnesota-DuluthDuluthMN 55812USA

Objective:The objective of this work is to study the effects of porosity on mechanical and piezoelectric properties of polyvinylidene fluoride(PVDF)films for biomedical *** Statement:By investigating the piezoelectric properties of PVDF and the porosity effect on its electromechanical performance,there is potential for further development of PVDF as a hemodynamic sensor that can lead to further technological advancements in the biomedical field,benefiting patients and physicians ***:PVDF thin films have shown potential in the application of hemodynamic flow sensing and monitoring the effects on blood flow caused by prosthetic valve implantation via the transcatheter aortic valve replacement *** piezoelectric performance of PVDF films can be influenced by the porosity of the ***:In this study,strain tracking was performed on thin film PVDF specimens with various levels of porosity and pore sizes to determine the mechanical properties of the *** mechanical properties were used to model the PVDF material in COMSOL multiphysics software,in which compression test simulations were performed to determine the piezoelectric coefficient d33 of the ***:A decline in the elastic modulus was found to be highly inversely correlated with porosity of the specimens and the simulation results show that elastic modulus had a much greater effect on the piezoelectric properties than Poisson’s ***:A combination of experimental and computational techniques was able to characterize and correlate the mechanical properties of PVDF films of varying porosities to their piezoelectric properties.

关键词： piezoelectric porosity modulus

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Catalytic mechanisms of nickel nanoparticles for the improved dehydriding kinetics of magnesium hydride

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Journal of Magnesium and Alloys 2024年第10期12卷 4278-4288页

作者： Shuaijun Ding Yuqing Qiao Xuecheng Cai Congcong Du Yixuan Wen Xun Shen Lidong Xu Shuang Guo Weimin Gao Tongde Shen Clean Nano Energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao066004China Hebei Key Laboratory of Applied Chemistry College of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongChina Deakin University GeelongInstitute for Frontier MaterialsLocked Bag 20000VIC3220Australia

MgH_(2),albeit with slow desorption kinetics,has been extensively studied as one of the most ideal solid hydrogen storage *** such catalyst as Ni can improve the desorption kinetics of MgH_(2),whereas the catalytic role has been attributed to different substances such as Ni,Mg_(2)Ni,Mg_(2)NiH0.3,and Mg_(2)*** the present study,Ni nanoparticles(Ni-NPs)supported on mesoporous carbon(Ni@C)have been synthesized to improve the hydrogen desorption kinetics of MgH_(2).The utilization of Ni@C largely decreases the dehydrogenation activation energy from 176.9 to 79.3 kJ mol^(−1) and the peak temperature of dehydrogenation from 375.5 to 235℃.The mechanism of Ni catalyst is well examined by advanced aberration-corrected environmental transmission electron microscopy and/or x-ray *** the first dehydrogenation,detailed microstructural studies reveal that the decomposition of MgH_(2)is initially triggered by the Ni-NPs,which is the rate-limiting ***,the generated Mg reacts rapidly with Ni-NPs to form Mg_(2)Ni,which further promotes the dehydrogenation of residual MgH_(2).In the following dehydrogenation cycle,Mg_(2)NiH4 can rapidly decompose into Mg_(2)Ni,which continuously promotes the decomposition of MgH_(2).Our study not only elucidates the mechanism of Ni catalyst but also helps design and assemble catalysts with improved dehydriding kinetics of MgH_(2).

关键词： Hydrogen storage materials Magnesium hydride Ni nanoparticles Microscopic catalytic process Microstructure evolutions

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Magnetorheological damper parameter identification and its application in semi-active control of power equipment

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Noise and Vibration Worldwide 2024年第11期55卷 632-650页

作者： Wei, Huang Jian, Xu Yi, Yao Yongliang, Zhang Xin, Wang SINOMACH Technology Research Center of Engineering Vibration Control Beijing China Beijing China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern Mechanics University of Science and Technology of China Hefei China

In recent years, magnetorheological dampers (MRD) have played a significant role in vibration control in various fields such as vehicles, military, building structures, etc. However, the mechanical model of MRD is very complex due to its hysteresis, which makes it difficult to identify the model’s parameters. In addition to experimental data, under the condition of no other prior knowledge, eight unknown parameters of the Bouc-Wen model are identified in this study based on the particle swarm optimization (PSO) algorithm. According to the trend of parameter variation with current, fitting research is conducted, and the variation law of parameters with current is summarized. Based on the identified parameters, the MRD’s output force is predicted under any current other than the experimental current. Subsequently, the application of MRD in semi-active control of power equipment is performed out, and proposed Simulink calculation programs for single-stage and two-stage vibration control systems are built. Then, a comparative study with passive and active control is conducted. In this paper, linear quadratic regulator (LQR) control is adopted for the active control, and the controller’s parameters are optimized based on the PSO algorithm. The results show that the adopted semi-active control can significantly reduce the transmitted force from power equipment to the foundation and can effectively mitigate the disturbance of power equipment to the environment. This study offers important guidance for the vibration control of MRD in industrial engineering. © The Author(s) 2024.

关键词： Vibration control

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A novel filament design for improving fused filament fabrication of continuous fiber composites

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Journal of materials Research and Technology 2025年 37卷 231-241页

作者： M. Parker S. Norimatsu R. Matsuzaki D. Arola Department of Materials Science and Engineering University of Washington Seattle WA USA Department of Mechanical Engineering Tokyo University of Science Tokyo Japan Department of Mechanical Engineering University of Washington Seattle WA USA

Fused filament fabrication (FFF) of polymer composites with continuous fibers could enable the manufacture of complex structures with exceptionally high specific strength and stiffness. Although filaments with continuous fiber reinforcement are “printable”, the fibers undergo damage during printing, leading to reductions in strength and reliability. Of further concern, the printed material generally exhibits low interlaminar tensile strength. In this study, a novel prototype filament for FFF with continuous carbon fibers and polyphenylene sulfide matrix was evaluated for its potential to resist process-related fiber damage introduced during printing and to increase the interlaminar tensile strength. The filament design enrolls a circumferential matrix coating around a fiber reinforced core. According to the measures of strength, the new filament design improved the reliability in axial strength as well as increased the interlaminar tensile strength by over 80 %. While the new coated filament exhibited superior performance overall in the printed condition, it was more sensitive to temperature changes and underwent a substantial decrease in axial tensile strength at T > 330 °C due to the decrease in matrix viscosity and consequent reduction in fiber protection. The printability of the new filament design is reported as a function of nozzle temperature, and the mechanisms that cause void formation and fiber damage are discussed.

关键词： Continuous fibers Fused filament fabrication Matrix coating Reliability Strength Interlaminar tensile strength

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On the transferability of post-processing heat treatments designed for PBF-LB IN718 alloys to directed energy deposition specimens

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International Journal of Advanced Manufacturing Technology 2025年第7期137卷 3949-3965页

作者： Serrano-Munoz, Itziar Agudo Jácome, Leonardo Thompsom, Sean Schneider, Judy Unter den Eichen 87 BerlinD-12205 Germany Materials Science and Engineering Division Propulsion and Structures Technology Development Directorate FCDD-AMT-MPS HuntsvilleAL35808 United States Department of Mechanical and Aerospace Engineering University of Alabama in Huntsville HuntsvilleAL35899 United States

Many processes are being developed for metal additive manufacturing (AM) which vary by their heat source and feedstock. The use of directed energy deposition (DED) is growing due to its ability to build larger structures outside of a contained powder bed chamber. However, the only standard exclusively for post-build heat treatment of AM IN718 is ASTM standard F3055-14a, developed for powder bed fusion (PBF). This study evaluates the applicability of this current heat treatment standard to AM IN718 specimens produced using two methods of DED: laser-blown powder (LP)-DED and arc-wire (AW)-DED. Electron microscopy and X-ray diffraction techniques were used to characterize the specimens in the as-built condition and after the full heat treatment (FHT) specified in F3055. No evidence of remaining Laves phase was observed in the two DED specimens after the FHT. Yield strengths for the DED specimens were 1049 MPa for FHT AW-DED and 1096 MPa for LP-DED, higher than the minimum stated for PBF-LB IN718 of 920 MPa. The size, morphology, inter-spacing, and diffraction patterns of the γ´ and γ´´ strengthening precipitates are found to be similar for both DED processes. Differences were observed in the microstructure evolution where the F3055 heat treatments resulted in partial recrystallization of the grain structure, with a higher content of annealing twins observed in the AW-DED. These microstructural differences correlate with differences in the resulting elongation to failure. Thus, it is proposed that variations in heat treatments are needed for optimizing IN718 produced by different AM processes. © The Author(s) 2025.

关键词： After-heat treatment

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Multivariate relationships between microstructure evolution and strengthening mechanisms in laser powder bed fusion of Al-Mn-Sc alloy:towards improved fatigue performance

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Light(Advanced Manufacturing) 2024年第1期5卷 3-18页

作者： Huaping Tang Chaofeng Gao Shiheng Zhang Xiaojing Xiong Sheng Cao Xiaopeng Wu Yunjie Bi Jeremy Heng Rao Institute of Advanced Additive Manufacturing Ji Hua LaboratoryFoshanGuangdong528200China Department of Mechanical Engineering College of EngineeringShantou UniversityShantouGuangdong515063China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

The effects of direct aging treatment(at 300℃ for 5 hours)on selective laser melted(SLMed)Al-4.5Mn-1.5Mg-0.9Sc-0.2Zr alloy were investigated in this work,with the microstructure,fatigue behaviors,and fracture characteristics examined to determine the primary cause of fatigue crack *** results revealed that the microstructure of the investigated alloy comprised fine equiaxed and columnar *** aging treatment,a significant number of nano-scaled Al3(Sc,Zr)precipitates were dispersed within the grains,leading to a substantial increase in *** yield strength improved from 431 MPa to 568 MPa,representing an increase of more than 32%,while the fatigue strength improved from 180 MPa to 220 MPa after aging ***,the fracture toughness decreased significantly from 25.1 MPa·√m to 12.3 MPa·√*** results of the fatigue fracture characteristics indicate that the Mn-rich phase and the formation of defects such as pores and poor powder fusion are the sources of fatigue *** direct aging treatment can significantly increase the yield strength,decrease the rate of fatigue crack propagation,and thus improve the fatigue performance,it deteriorates the fracture toughness,and thus shortens the fatigue life of the alloy as well.

关键词： Selective laser melting Al-Mn-Sc alloys High-cycle fatigue

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Tailoring hydrogen embrittlement resistance of pure Ni by grain boundary engineering

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Corrosion Communications 2022年第2期6卷 48-51页

作者： Qingqing Sun Jinhua Han Jiaxing Li Fahe Cao Shuai Wang Department of Mechanical and Energy Engineering Southern University of Science and Technology School of Materials Sun Yat-sen University

By using thermo-mechanical processing, 99.996 wt.% pure Ni with different grain boundary characteristics were fabricated(Sample #1, 700℃ × 10 h + cold rolling reduction 50%+ 650℃ × 2 h; Sample #2, 700℃ × 10 h + cold rolling reduction 50%+ 900℃ × 5 min). Hydrogen embrittlement sensitivity of the two samples was determined by using high-pressure hydrogen charging, low strain rate tensile test and SEM fractography. Compared with Sample #1, hydrogen embrittlement index of Sample #2 increased from 0.52 to 0.71. The effects of grain size,grain boundary type and grain boundary curviness on hydrogen embrittlement of pure Ni were discussed. The results indicate that: 1) special grain boundaries including twin grain boundaries may have a marginal effect on tailoring hydrogen embrittlement resistance in pure Ni; 2) increasing grain boundary curviness is an effective way to improve hydrogen embrittlement resistance of Ni.

关键词： Alloy Hydrogen embrittlement Microstructure Grain boundary engineering

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Electrochemically Modulated Metasurfaces

Electrochemically Modulated Metasurfaces

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2023 Conference on Lasers and Electro-Optics, CLEO 2023

作者： Eaves-Rathert, Janna Kovalik, Elena Ugwu, Chibuzor Fabian Pint, Cary L. Valentine, Jason G. Department of Mechanical Engineering Vanderbilt University NashvilleTN37212 United States Interdisciplinary Materials Science Program Vanderbilt University NashvilleTN37212 United States Department of Mechanical Engineering Iowa State University AmesIA50011 United States

Electrochemical intercalation of lithium in titanium dioxide and silicon-based metasurfaces is used to initiate phase changes in a continuously tunable, reversible, and bistable manner for dynamic control over structu... 详细信息

ISBN: (纸本)9781957171258

关键词： Titanium dioxide

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Material Removal Mechanism and Force Modeling in Ultrasonic Vibration-Assisted Micro-Grinding Biological Bone

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Chinese Journal of mechanical engineering 2023年第5期36卷 20-44页

作者： Jingang Sun Changhe Li Zongming Zhou Bo Liu Yanbin Zhang Min Yang Teng Gao Mingzheng Liu Xin Cui Benkai Li Runze Li Yusuf Suleiman Dambatta Shubham Sharma School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266520China Sichuan Future Aerospace Industry LLC. Shifang 618400China Department of Biomedical Engineering University of Southern CaliforniaLos AngelesCA 90089USA Mechanical Engineering Department Ahmadu Bello UniversityZaria 810106Nigeria Department of Mechanical Engineering and Advanced Materials Science Regional Center for Extension and DevelopmentCouncil of Scientifc and Industrial Research(CSIR)-Central Leather Research Institute(CLRI)Jalandhar 144021India

Micro-grinding with a spherical grinding head has been deemed an indispensable method in high-risk surgeries, such as neurosurgery and spine surgery, where bone grinding has long been plagued by the technical bottleneck of mechanical stress-induced crack damage. In response to this challenge, the ultrasound-assisted biological bone micro-grinding novel process with a spherical grinding head has been proposed by researchers. Force modeling is a prerequisite for process parameter determination in orthopedic surgery, and the difculty in establishing and accurately predicting bone micro-grinding force prediction models is due to the geometric distribution of abrasive grains and the dynamic changes in geometry and kinematics during the cutting process. In addressing these critical needs and technical problems, the shape and protrusion heights of the wear particle of the spherical grinding head were frst studied, and the gradual rule of the contact arc length under the action of high-speed rotating ultrasonic vibration was proposed. Second, the mathematical model of the maximum thickness of undeformed chips under ultrasonic vibration of the spherical grinding head was established. Results showed that ultrasonic vibration can reduce the maximum thickness of undeformed chips and increase the range of ductile and bone meal removals, revealing the mechanism of reducing grinding force. Further, the dynamic grinding behavior of diferent layers of abrasive particles under diferent instantaneous interaction states was studied. Finally, a prediction model of micro-grinding force was established in accordance with the relationship between grinding force and cutting depth, revealing the mechanism of micro-grinding force transfer under ultrasonic vibration. The theoretical model’s average deviations are 10.37% in x-axis direction, 6.85% in y-axis direction, and 7.81% in z-axis direction compared with the experimental results. This study provides theoretical guidance and technical sup

关键词： Spherical grinding head Gradual contact arc length Maximum undeformed chip thickness Microgrinding force

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