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Employment of Finite Element Analysis Method to Analyze the Thermal Effects of Direct Energy Deposition on SUS316L

Sensors and materials 2024年第4期36卷 1693-1706页

作者： Zheng, Wenjie Chang, Hung-Yu Hsu, Chao-Ming Yang, Cheng-Fu School of Ocean Information Engineering Jimei University Fujian Xiamen361021 China Department of Mechanical Engineering National Kaohsiung University of Science and Technology Kaohsiung807 Taiwan Department of Chemical and Materials Engineering National University of Kaohsiung Kaohsiung811 Taiwan Department of Aeronautical Engineering Chaoyang University of Technology Taichung413 Taiwan

In this study, we investigated the displacement behavior of SUS316L stainless steel under five consecutive direct energy depositions through experiments and the use of the ANSYS commercial finite element method software. We explored the effects of displacement after cooling the five deposited layers and examined the relationship between different curvatures and laser parameters, including laser power and laser feed rate. In this research, a complete cross-sectional profile was obtained through experiments. Subsequently, simulations were conducted using laser powers of 300, 400, and 500 W, along with laser feed rates of 3, 5, and 7 mm/s, employing a thermal-solid coupling model. The results indicated that the optimal preheating temperature during the deposition process was around 150 °C, leading to a more stable displacement difference. The influence of curvature on displacement was relatively consistent along the neutral axis, allowing for the prediction of large displacement amounts along a straight-line path. Through simulation, it could be understood that when utilizing direct energy deposition to deposit SUS316L, considering the displacement conditions during the deposition process, it was preferable to use a low laser power and a high deposition rate. © MYU K.K.

关键词： Finite element method

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Artificial neural networks modelling for surface roughness in wire electrical discharge machining of Incoloy 800H 15

Artificial neural networks modelling for surface roughness i...

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15th International Conference on Computing Communication and Networking Technologies, ICCCNT 2024

作者： Paturi, Uma Maheshwera Reddy Goturi, Sheshank Reddy Bhojane, Omkar Sunil Sahasra Konidhala, Nandan Nudurupati, Achintya Vamshi Reddy, N.S. Cvr College of Engineering Department of Mechanical Engineering Telangana Hyderabad India Gyeongsang National University School of Materials Science and Engineering Jinju Korea Republic of

ISBN: (纸本)9798350370249

The use of artificial neural networks (ANNs) in optimizing process parameters and model development has gained attention due to their ability to predict timely and accurate outputs. The current study uses ANNs to predict surface roughness during wire electrical discharge machining (WEDM) of Incoloy 800H. The prediction model utilizes a multilayer perception based on back-propagation neural network (BPNN). In neural network modelling, network weights and bias values were updated, and the process output was estimated using the Levenberg-Marquardt backpropagation training function (trainlm) and a hyperbolic tangent sigmoid (tansig) transfer function, respectively. The ANN model comprises one output neuron (surface roughness) and five input neurons (pulse on, pulse off, wire tension, servo voltage, and wire feed rate). WEDM experimental data is divided into training, testing, and validation in the ratio of 70%:15%:15%. The results show that the optimal ANN model with 5-11-1 topology provides an accurate estimate of surface roughness, with a correlation coefficient of 0.997. The proposed ANN model can predict WEDM process parameters quickly and effectively. © 2024 IEEE.

关键词： Artificial neural networks Incoloy 800H Modelling Surface roughness WEDM

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Unraveling abnormal buried interface anion defect passivation mechanisms depending on cation-induced steric hindrance for efficient and stable perovskite solar cells

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Journal of Energy Chemistry 2023年第5期80卷 1-9,I0001页

作者： Dongmei He Ru Li Baibai Liu Qian Zhou Hua Yang Xuemeng Yu Shaokuan Gong Xihan Chen Baomin Xu Shangfeng Yang Jiangzhao Chen Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) College of Optoelectronic EngineeringChongqing UniversityChongqing 400044China Institute of High Energy Physics Chinese Academy of Sciences(CAS)Bejing 100049Chin SUSTech Energy Institute for Carbon Neutrality Department of Mechanical and Energy EngineeringSouthern University of Science and TechnologyShenzhen 518055GuangdongChin Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina CAS Key Laboratory of Materials for Energy Conversion Department of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

Although ionic liquids(ILs)have been widely employed to heal the defects in perovskite solar cells(PSCs),the corresponding defect passivation mechanisms are not thoroughly understood up to ***,we first reveal an abnormal buried interface anion defect passivation mechanism depending on cationinduced steric *** IL molecules containing the same anion([BF4]^(-))and different sizes of imidazolium cations induced by substituent size are used to manipulate buried *** was revealed what passivated interfacial defects is mainly anions instead of *** and experimental results demonstrate that the large-sized cations can weaken the ionic bond strength between anions and cations,and facilitate the interaction between anions and SnO2as well as perovskites,which is conducive to interfacial defect passivation and ameliorating interfacial *** can be concluded that interfacial chemical interaction strength and defect passivation effect are positively correlated with the size of *** discovery breaks conventional thinking that large-sized modification molecules would weaken their chemical interaction with *** with the control device(21.54%),the device based on 1,3-Bis(1-adamantyl)-imidazolium tetrafluoroborate(BAIMBF4)with maximum size cations achieves a significantly enhanced efficiency of 23.61%along with much increased moisture,thermal and light stabilities.

关键词： Perovskite solar cells Buried interface Ionic liquid Anion defect passivation mechanism Cation-induced steric hindrance

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Symmetry breaking in spoke double-ring structures formed by buckling-guided 3D assembly

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Theoretical & Applied Mechanics Letters 2025年第1期15卷 25-31页

作者： Xiaoran Yang Jianzhong Zhao Alexander Hartmaier Yonggang Huang Yihui Zhang Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Laboratory of Flexible Electronics Technology Tsinghua UniversityBeijing 100084China Interdisciplinary Center for Advanced Materials Simulation(ICAMS) Ruhr-Universität BochumBochum 44801Germany Department of Civil and Environmental Engineering Northwestern UniversityEvanstonIL 60208USA Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA Department of Materials Science and Engineering Northwestern UniversityEvanstonIL 60208USA

The buckling-guided three-dimensional(3D)assembly method has arisen increasing attention for its advantages in forming complex 3D architectures with a rich diversity of geometric shapes in a broad spectrum of inorganic functional *** an assembly method relies on the controlled lateral bucking of a 2D precursor structure integrated with a pre-stretched substrate at selective *** the assembly process,the preservation or break-ing of rotational symmetry is crucial for understanding the mechanism of 2D-to-3D geometric ***,we present a fundamental study on the rotational symmetry of 3D spoke double-ring structures formed through buckling-guided *** energetic method is introduced to analyze the rotational symmetry and to understand the symmetry-breaking *** symmetry-breaking phenomenon is validated by experi-ments and finite element analyses(FEA).Phase diagrams of the deformation mode are established to shed light on the influences of various geometric parameters(e.g.,initial rotational symmetry order,radius ratio,and lo-cation of bonding sites).This work offers new insights into the underlying mechanism of 2D-to-3D geometric transformation in ribbon-type structures formed by compressive buckling.

关键词： Buckling-guided 3D assembly Rotational symmetry Post-buckling Instability

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Effects of Al addition and cryogenic cyclic treatment on impact toughness of phase-transformable Ti-based bulk metallic glass composites

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Journal of materials science & Technology 2023年第9期140卷 210-220页

作者： Tingyi Yan Long Zhang R.Lakshmi Narayan Jingyu Pang Yi Wu Huameng Fu Hong Li Upadrasta Ramamurty Haifeng Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Materials Science and Engineering Indian Institute of Technology DelhiHauz KhasNew Delhi 110016India Department of Mechanical and Aerospace Engineering in Nanyang Technological University Singapore 637331Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A∗STAR)Singapore 138634Singapore

Developing bulk metallic glass composites(BMGCs)with high toughness is vital for their practical ***,the influence of different microstructures on the impact toughness of BMGCs is still *** effects of Al addition and cryogenic cyclic treatment(CCT)on the Charpy impact toughness,a K,at 298 and 77 K of a series of phase-transformable BMGCs are investigated in this *** is found that deformation-induced martensitic transformation(DIMT)of theβ-Ti dendrites is the dominant toughening mechanism in the phase-transformable BMGCs at 298 K,but at 77 K,the toughness of BMGCs is primarily determined by the intrinsic toughness of the glass *** addition of Al can moderately tune theβ-Ti phase stability,which then affects the amount of DIMT and impact toughness of the BMGCs at 298 ***,at 77 K,Al addition causes a monotonic decrease in the toughness of the BMGCs due to the embrittlement of the glass *** is found that CCT can effectively rejuvenate the phase-transformable BMGCs,which results in an enhanced impact toughness at 298 ***,the toughness at 77 K monotonously decreases with increasing the number of CCT cycles,suggesting that the rejuvenation of the glass matrix affects the toughness at both 298 and 77 K of BMGCs,but in dramatically different *** findings reveal the influence of microstructures and CCT on the impact toughness of BMGCs and provide insights that could be useful for designing tougher BMGs and BMGCs.

关键词： Bulk metallic glass composites Charpy impact toughness Deformation-induced martensitic transformation Metastability Thermal cycling rejuvenation

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X-ray and molecular dynamics study of the temperature-dependent structure of molten NaF-ZrF4

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Physical Review materials 2024年第7期8卷 075402-075402页

作者： Anubhav Wadehra Rajni Chahal Shubhojit Banerjee Alexander Levy Yifan Zhang Haoxuan Yan Daniel Olds Yu Zhong Uday Pal Stephen Lam Karl Ludwig Division of Materials Science and Engineering Chemical Science Division Department of Chemical Engineering Department of Mechanical Engineering Department of Mechanical and Materials Engineering National Synchrotron Light Source II Department of Physics

The local atomic structure of NaF-ZrF4 (53–47 mol%) molten system and its evolution with temperature are examined with x-ray scattering measurements which are then used to validate the quality of ab initio and neural network-based molecular dynamics (NNMD) calculations in the temperature range 515−700∘C. The machine-learning enhanced NNMD calculations offer improved efficiency while maintaining accuracy at higher distances compared to ab initio calculations. Looking at the evolution of the pair distribution function with increasing temperature, a fundamental change in the liquid structure within the selected temperature range, accompanied by a slight decrease in overall correlation is revealed. NNMD calculations indicate the coexistence of three different fluorozirconate complexes: [ZrF6]2−, [ZrF7]3−, and [ZrF8]4−, with a shift in the dominant coordination state from the 7-coordinated Zr cation toward a 6-coordinated cation with increasing temperature. The study also highlights the metastability of different local coordination structures, with frequent interconversions between the 6- and 7-coordinate states. Analysis of the Zr-F-Zr angular distribution function reveals the presence of both “edge-sharing” and “corner-sharing” fluorozirconate complexes with specific bond angles and distances in accord with previous studies, while the next-nearest-neighbor cation-cation correlations demonstrate a clear preference for unlike cations as nearest-neighbor pairs, emphasizing nonrandom arrangement. These findings contribute to a comprehensive understanding of the complex local structure of the molten salt, providing insights into temperature-dependent preferences and correlations within the molten system.

关键词： Atomic & molecular structure Ionic fluids Liquids Ab initio molecular dynamics Machine learning X-ray pair-distribution function analysis X-ray scattering

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High sound pressure piezoelectric micromachined ultrasonic transducers using sputtered potassium sodium niobate

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Microsystems & Nanoengineering 2024年第6期10卷 311-323页

作者： Fan Xia Yande Peng Wei Yue Mingze Luo Megan Teng Chun-Ming Chen Sedat Pala Xiaoyang Yu Yuanzheng Ma Megha Acharya Ryuichi Arakawa Lane W.Martin Liwei Lin Department of Mechanical Engineering University of CaliforniaBerkeleyCA 94720USA School of Electronic Science and Engineering Southeast UniversityNanjingJiangsu 210096China Bioengineering and Biomedical Engineering Xi’an Jiaotong UniversityXi’anShaanxi 710049China Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen 518055China Department of Materials Science and Engineering University of CaliforniaBerkeleyCA 94720USA Scientific Research Laboratory Div. Niterra Co.LtdNagoya 461-0005Japan Departments of Materials Science and NanoEngineering Chemistryand Physics and Astronomy and the Rice Advanced Materials InstituteRice UniversityHoustonTX 77005USA

This work presents air-coupled piezoelectric micromachined ultrasonic transducers(pMUTs)with high sound pressure level(SPL)under low-driving voltages by utilizing sputtered potassium sodium niobate K0.34Na0.66NbO3(KNN)films.A prototype single KNN pMUT has been tested to show a resonant frequency at 106.3 kHz under 4 Vp-p with outstanding characteristics:(1)a large vibration amplitude of 3.74μm/V,and(2)a high acoustic root mean square(RMS)sound pressure level of 105.5 dB/V at 10 cm,which is 5–10 times higher than those of AlN-based pMUTs at a similar *** are various potential sensing and actuating applications,such as fingerprint sensing,touch point,and gesture *** this work,we present demonstrations in three fields:haptics,loudspeakers,and *** haptics,an array of 15×15 KNN pMUTs is used as a non-contact actuator to provide a focal pressure of around 160.3 dB RMS SPL at a distance of 15 *** represents the highest output pressure achieved by an airborne pMUT for haptic sensation on human *** used as a loudspeaker,a single pMUT element with a resonant frequency close to the audible range at 22.8 kHz is *** is shown to be able to generate a uniform acoustic output with an amplitude modulation *** the rangefinder application,pulse-echo measurements using a single pMUT element demonstrate good transceiving results,capable of detecting objects up to 2.82 m *** such,this new class of high-SPL and low-driving-voltage pMUTs could be further extended to other applications requiring high acoustic pressure and a small form factor.

关键词： potassium piezoelectric sound

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Correlation between hydration properties and electrochemical performances on Ln cation size effect in layered perovskite for protonic ceramic fuel cells

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Journal of Energy Chemistry 2024年第1期88卷 1-9,I0001页

作者： Inhyeok Cho Jiwon Yun Boseok Seong Junseok Kim Sun Hee Choi Ho-Il Ji Sihyuk Choi Department of Mechanical Engineering Kumoh National Institute of TechnologyGumi 39177GyeongbukRepublic of Korea Department of Aeronautics Mechanical and Electronic Convergence EngineeringKumoh National Institute of TechnologyGumi 39177GyeongbukRepublic of Korea Center for Energy Materials Research Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Center for Hydrogen and Fuel Cell Research Clean Technology Research DivisionKorea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Department of Energy and Environmental Engineering University of Science and TechnologySeoul 02792Republic of Korea Nanomaterials Science and Engineering Korea University of Science and Technology(UST)KIST CampusSeoul 02792Republic of Korea

PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula for Pr BSCF is AA'B_(2)O_(5+δ), with Pr(A-site) and Ba/Sr(A'-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer;thus, the A site cations(lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects,whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(LnBSCF,Ln=Pr, Nd, and Gd) cathodes. At 500 ℃, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of Pr BSCF < Nd BSCF < Gd BSCF. To elucidate the close relationship between hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated.

关键词： Protonic ceramic fuel cell Cathode Triple ionic and electronic conductor Hydration property Proton uptake Gibbs free energy

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A Low-cost Surface Modified Battery-used Polyethylene Membranes for Reverse Osmosis Applications

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materials Research Innovations 2023年第5期27卷 348-354页

作者： Song, Yiye Zhang, Ye Yang, Hongjun Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials School of Materials Science and Engineering Jiangsu Collaborative Innovation Centre of Photovoltaic Science and Engineering Changzhou University Changzhou213164 China Department of Mechanical and Material Engineering Changzhou University Huaide College Jingjiang214500 China

Reverse osmosis (RO) membranes have been widely used in the field of membrane separation. However, most of the commercial RO membranes are fabricated based on a polysulphones- or polyethersulfone-modified polyethylene glycol terephthalate (PET) support, which are thick and exhibit poor solvent resistance. In this study, polyethylene (PE) battery membranes without any hydrophilic modification were directly used to prepare PE-RO membranes. The structures of the products were confirmed via attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The resulting RO membrane prepared with 0.05 wt.% of trimesoyl chloride and 2 wt.% of m-phenylenediamine exhibited a water flux of 12.61 L m−2 h−1 with a desalination (NaCl) rate of 98.6%. The thickness of the PE-RO membrane is 80% of the thickness of the traditional RO membranes and hence has a wider application as a separation membrane. © 2022 Informa UK Limited, trading as Taylor & Francis Group.

关键词： Polyethylenes

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Analyzing the Effects of Milling and Sintering Parameters on Crystalline Phase Evolution and mechanical Properties of Al_(86)Ni_(8)Y_(6) and Al_(86)Ni_(6)Y_(4.5)Co_(2)La_(1.5) Amorphous Ribbons

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Acta Metallurgica Sinica(English Letters) 2022年第6期35卷 1043-1054页

作者： Ashutosh Sahu Ram Sajeevan Maurya Lavish Kumar Singh Tapas Laha Department of Mechanical Engineering School of Engineering and TechnologySharda UniversityGreater Noida 201310India Department of Metallurgy Engineering and Materials Science Indian Institute of Technology IndoreIndore 453552India Department of Metallurgical and Materials Engineering Indian Institute of Technology KharagpurKharagpur 721302India

In the present study,Al_(86)Ni_(8)Y_(6) and Al_(86)Ni_(6)Y_(4.5)Co_(2)La_(1.5) bulk amorphous nanocomposites were synthesized by spark plasma sintering of milled melt spun ribbon *** as-cast ribbons were of near amorphous nature with minute amount of FCC Al embedded in the amorphous *** of the ribbons resulted in partial devitrifi cation due to mechanical *** milled ribbon particles were sintered in the temperature and pressure range of 300-500℃ and 500-700 MPa,*** was observed that nominal amount of amorphous phase was retained at 500℃ and 500 *** increase in sintering pressure and decrease in sintering temperature,the amount of crystalline phase evolution decreased,and maximum amount of amorphous phase was retained at 300℃ and 700 *** microstructure consisting of amorphous phase embedded with hard intermetallic phases led to increase in the nanohardness of Al_(86)Ni_(8)Y_(6) and Al_(86)Ni_(6)Y_(4.5)Co_(2)La_(1.5) as-cast ribbons from 3.26±0.59 GPa and 3.81±0.58 GPa to 6.06±0.70 GPa and 6.14±0.82 GPa,respectively,for the corresponding consolidated amorphous *** of the three and five component system bulk samples was 4.19±0.13GPa and 3.6±0.13 GPa,respectively.

关键词： Amorphous alloy Milled ribbon Spark plasma Sintering Nanohardness Internetallic compound

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