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Machine Learning-Based Quantitative Analysis of Metal Ductile Fracture Surface

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SSRN 2023年

作者： Zhang, Neng Fu, Hao Liu, Pei Wang, Changxin Zhang, Yan Lookman, Turab Huang, Haiyou Su, Yanjing Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China AECC Guizhou Liyang Aviation Power Co. Ltd. Guiyang550014 China Guizhou Key Laboratory of Materials Mechanical Behavior and Microstructure College of Materials and Metallurgy Guizhou University Guiyang550025 China Shunde Innovation School University of Science and Technology Guangdong Beijing528399 China Beijing Key Laboratory of Advanced High Temperature Materials Central Iron & Steel Research Institute Beijing100081 China Beijing GAONA Materials & Technology Co. LTD Beijing100081 China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology Beijing Beijing100083 China Beijing Key Laboratory of Materials Genome Engineering University of Science and Technology Beijing Beijing100083 China AiMaterials Research LLC Santa FeNM87501 United States

Quantitative fracture analysis （QFA） can infer mechanical properties and fracture mechanism of materials based on quantitative statistics of various topographical features on the fracture surface. However, it is still a challenge to screen the key fracture surface descriptors for a certain property through experimental induction and theoretical derivation and to deduce the accurate quantitative relationship between them due to different properties involving a variety of fracture surface descriptors. Herein, a QFA strategy based on machine learning was proposed. The fracture surface images were first divided into three classes, intergranular, quasi-cleavage and dimple by an unsupervised classification model based on convolutional neural network with the accuracy of 0.867. The fracture surface descriptors of the identified dimple images were extracted by image segmentation method and used to train separate regression models to predict the values of fracture toughness (KIC ), tensile strength (Rm ), yield strength (Re ), elongation after fracture (A) and fracture shrinkage (Z). These models also demonstrate good performance with R2 in the test set are 0.934, 0.944, 0.840, 0.890, 0.900, respectively. In addition, with KIC and Rm as dependent variables, the explicit relationships between them and key morphological features were established based on symbolic regression. The R2 between the predicted and experimental values of the two formulas reach 0.925 and 0.926, respectively. This machine learning-based quantitative analysis tool can assist in the rapid prediction and evaluation of mechanical properties of materials in engineering applications scenarios. © 2023, The Authors. All rights reserved.

关键词： Ductile fracture

Hamiltonian Dynamics and Targeted Energy Transfer of a Grounded Bistable Nonlinear Energy Sink

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SSRN 2022年

作者： Li, Shuangbao Zhou, Xinxing Chen, Jianen Research Institute of Science and Technology Civil Aviation University of China Tianjin300300 China College of Science Civil Aviation University of China Tianjin300300 China Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical Engineering Tianjin University of Technology Tianjin300384 China

A two-degree-of-freedom nonlinear mechanical system describing a damped linear oscillator weakly coupled to a lightweight grounded bistable nonlinear energy sink is proposed to investigate the targeted energy transfer (TET) under asymmetric local nonlinear potentials. The Bogdanov-Takens bifurcations of equilibria are discussed to reflect the bistable and asymmetric characteristics of the system. Through projections of isoenergetic manifolds, the topological features of the Hamiltonian dynamics under $1:1$ internal resonance have been investigated, which induces conditions for energy localization and exchange. In the general case, the topological features of the Hamiltonian dynamics related to the nonlinear normal modes (NNMs) are classified by the Poincare map, the relations between the NNMs and the Hamiltonian dynamics have been interpreted through the frequency energy plots. The results show that introducing the asymmetric characteristics may enhance the TET and realize the complete TET. © 2022, The Authors. All rights reserved.

关键词： Degrees of freedom (mechanics)

Frequency-dependent squeezing via Einstein–Podolsky–Rosen entanglement based on silicon nitride microring resonators

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arXiv

arXiv 2024年

作者： Xu, Haodong Shu, Zijun Li, Nianqin Shen, Yang Ji, Bo Yang, Yongjun Wu, Tengfei Long, Mingliang He, Guangqiang State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiao Tong University Shanghai200240 China State Key Laboratory of Precision Spectroscopy East China Normal University Shanghai200062 China Science and Technology on Metrology and Calibration Laboratory Changcheng Institute of Metrology Measurement Aviation Industry Corporation of China Beijing100095 China Shanghai Astronomical Observatory Chinese Academy of Sciences China

Significant efforts have been made to enhance the performance of displacement sensors limited by quantum noise, such as gravitational wave detectors. Techniques like frequency-dependent squeezing have overcome the standard quantum limit in optomechanical force measurements, leading to substantial overall progress. These advancements, coupled with major developments in integrated photonics, have paved the way for the emergence of integrated Kerr quantum frequency combs (QFCs). A platform has been established for designing EPR entangled quantum frequency combs using on-chip silicon nitride microring resonators, enabling thorough analysis and optimization of entanglement performance, as well as effective noise reduction adjustments. This platform, incorporating the quantum dynamics of Kerr nonlinear microresonators, supports at least 12 continuous-variable quantum modes in the form of 6 simultaneous two-mode squeezed pairs (EPR entangled pairs). Additionally, by selecting the detection angle of the idler mode, a single-mode squeezed state is generated in the signal mode. Given the frequency-dependent nature of the detection angle, frequency-dependent squeezing is achieved. A comparative analysis of the results under different dispersion conditions is also conducted. Copyright © 2024, The Authors. All rights reserved.

关键词： Silicon nitride

Effects of Wo3 and Moo3 Loadings on Vanadia-Based Catalysts for Nh3-Scr: Revealed by in Situ Infrared and Two-Dimensional Correlation Spectroscopy

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SSRN 2023年

作者： Lv, Zhihui He, Guangzhi Ge, Yanli Liu, Yongchun Yu, Yunbo He, Hong State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing100085 China University of Chinese Academy of Sciences Beijing100049 China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing Innovation Center for Engineering Science and Advanced Technology College of Environmental Science and Engineering Peking University Beijing100871 China Aerosol and Haze Laboratory Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Beijing100029 China Ganjiang Innovation Academy Chinese Academy of Sciences Ganzhou341000 China Center for Excellence in Regional Atmospheric Environment Key Laboratory of Urban Pollutant Conversion Institute of Urban Environment Chinese Academy of Sciences Xiamen361021 China

Vanadia-based catalysts have been widely applied in NOx reduction, while the promoting effects of WO3 and MoO3 are still under debate. Herein, we prepared V2O5/TiO2, V2O5-WO3/TiO2, and V2O5-MoO3/TiO2 catalysts and revealed that WO3 and MoO3 enhanced the activity of V2O5/TiO2, especially under wet conditions. In situ DRIFTS, two-dimensional correlation spectroscopy (2D COS), and DFT calculations demonstrated that NH3 adsorbed on Lewis acid sites of V2O5/TiO2, resulting in the formation of NH3ads-L1 (1284 cm-1, Ti sites of O=V-O-Ti) and NH3ads-L2 (1604 cm-1, V=O sites). By using 2D COS, we found that the NH3ads-L1 exhibited higher reactivity towards NO to produce NH2NO* via NH2*, which was promoted by WO3. Moreover, WO3 and MoO3 doping inhibited H2O adsorption, and promoted its desorption by increasing temperature, thus protecting the V=O sites on V2O5/TiO2. Also, 2D COS provided a new perspective for in-depth understanding of the active sites and intermediates in the NH3-SCR reaction. © 2023, The Authors. All rights reserved.

关键词： Catalysts

Time-Resolved in Situ Infrared and Two-Dimensional Correlation Spectroscopy of V2o5/Tio2: Effects of Wo3 and Moo3 Loadings for Nh3-Scr

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SSRN 2023年

Vanadia-based catalysts are widely applied in NOx reduction, while the promoting effect of WO3 and MoO3 is still under debate. Herein, we prepared V2O5/TiO2, V2O5-WO3/TiO2, and V2O5-MoO3/TiO2 catalysts and revealed that WO3 and MoO3 enhanced the activity of V2O5/TiO2, particularly under wet conditions. In situ DRIFTS, two-dimensional correlation spectroscopy (2D COS), and DFT calculations demonstrated that NH3 adsorption on Lewis acid sites of V2O5/TiO2 resulted in the formation of NH3ads-L1 (1284 cm-1, Ti sites of O=V-O-Ti) and NH3ads-L2 (1604 cm-1, V=O sites). By using 2D COS, we firstly found that the NH3ads-L1 exhibited higher reactivity towards NO to produce NH2NO* via NH2*, which was promoted by WO3. Moreover, WO3 and MoO3 doping inhibited H2O adsorption, and promoted its desorption at elevated temperature, thus protecting the V=O sites on V2O5/TiO2. Also, 2D COS analysis provides a new perspective for in-depth understanding of the active sites and intermediates in NH3-SCR reaction. © 2023, The Authors. All rights reserved.

关键词： Catalysts

Dft Study of Defective H-Bas: Effective Adsorption for Radioactive Gaseous Iodine

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SSRN 2024年

作者： Zhou, Jie Wang, Na Kuang, Xiang-Jun Lei, Jie-Hong Chang, Xiang-Hui Song, Ting-Ting Bai, Jian-Hui School of Physics and Astronomy China West Normal University Nanchong637002 China School of Mathematics and Physics Southwest University of Science and Technology Mianyang621010 China Research Center for New Energy Materials China West Normal University Nanchong637002 China School of Physical Science and Technology Southwest Jiaotong University Key Laboratory of Advanced Technologies of Materials Ministry of Education of China Chengdu610031 China School of Aviation and Mechanical Engineering Changzhou Institute of Technology Changzhou213032 China

The adsorption behavior of iodine molecules on hexagonal boron arsenide (h-BAs) with and without defects has been systematically investigated using first-principles. The maximum adsorption energy of I2 on perfect h-BAs is -0.700 eV. However, in the presence of defects(vac-B and vac-As), the adsorption energy can be up to -5.007 eV. Forming I-As and I-B covalent bond with lengths of 2.764 and 2.189 Å, respectively, which is the typical bond length of the iodide. The substrate loses electrons of 0.215 e. I2 dissociates upon adsorption on vac-As, where iodine atom distances of up to 3.800 Å and breaking of the I-I bond. PDOS shows strong hybridization of B 2p and As 4p orbitals with I 5p orbital, there is clear orbital overlap in the range of -3.1 to -1.9 eV, with overlapping peaks at -2.5 and -2.1 eV. Iodine can effectively adsorb on h-BAs, especially in the presence of defects. This research is significant for developing promising iodine molecular adsorbents. © 2024, The Authors. All rights reserved.

关键词： Iodine

Augmenting photoluminescence of monolayer MoS_(2) using high order modes in a metal dimer-on-film nanocavity

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Photonics Research 2021年第4期9卷 501-506页

作者： Shiyin Cao Liping Hou Qifa Wang Chenyang Li Weixing Yu Xuetao Gan Kaihui Liu Malin Premaratne Fajun Xiao Jianlin Zhao MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710129China Key Laboratory of Spectral Imaging Technology of Chinese Academy of Sciences Xi’an 710119China State Key Laboratory for Mesoscopic Physics Collaborative Innovation Centre of Quantum MatterSchool of PhysicsPeking UniversityBeijing 100871China Advanced Computing and Simulation Laboratory(AχL) Department of Electrical and Computer Systems EngineeringMonash UniversityClaytonVIC 3800Australia

Plasmonic particle-on-film nanocavities,supporting gap modes with ultra-small volume,provide a great solution to boost light–matter interactions at the *** this work,we report on the photoluminescence(PL)enhancement of monolayer MoS_(2) using high order modes of an Au nanosphere dimer-on-film nanocavity(DoFN).The high order plasmon modes,consisting of two bonding quadrupoles in the dimer and their images in the Au film,are revealed by combining the polarization-resolved scattering spectra with the numerical *** integrating the monolayer MoS_(2) into the DoFN,these high order modes are used to enhance PL intensity through simultaneously boosting the absorption and emission processes,producing a 1350-fold enhancement *** opens an avenue to enhance the light–matter interaction with high order plasmon modes and may find applications in future optoelectronics and nanophotonics devices.

关键词： cavity high integrating

Prediction of fully metallic σ-bonded boron framework induced high superconductivity above 100 K in thermodynamically stable Sr2B5 at 40 GPa

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arXiv

arXiv 2023年

作者： Yang, Xin Zhao, Wenbo Ma, Liang Lu, Wencheng Zhong, Xin Xie, Yu Liu, Hanyu Ma, Yanming Key Laboratory of Material Simulation Methods & Software Ministry of Education College of Physics Jilin University Changchun130012 China State Key Laboratory for Superhard Materials College of Physics Jilin University Changchun130012 China International Center of Future Science Jilin University Changchun130012 China Key Laboratory of Physics and Technology for Advanced Batteries Ministry of Education College of Physics Jilin University Changchun130012 China

Metal borides have been considered as potential high-temperature superconductors since the discovery of record-holding 39 K superconductivity in bulk MgB2. In this work, we identified a superconducting yet thermodynamically stable F(Equation presented)3m Sr2B5 at 40 GPa with a unique covalent sp3-hybridized boron framework through extensive first-principles structure searches. Remarkably, solving the anisotropic Migdal-Eliashberg equations resulted in a high superconducting critical temperature (Tc) around 100 K, exceeding the boiling point (77 K) of liquid nitrogen. Our in-depth analysis revealed that the high-temperature superconductivity mainly originates from the strong coupling between the metalized σ-bonded electronic bands and E phonon modes of boron atoms. Moreover, anharmonic phonon simulations suggest that F(Equation presented)3m Sr2B5 might be recovered to ambient pressure. Our current findings provide a prototype structure with a full σ-bonded boron framework for the design of high-Tc superconducting borides that may expand to a broader variety of lightweight compounds. © 2023, CC BY.

关键词： High temperature superconductors

Interpretable machine-learning strategy for soft-magnetic property and thermal stability in Fe-based metallic glasses

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npj Computational Materials 2020年第1期6卷 1-9页

作者： Lu, Zhichao Chen, Xin Liu, Xiongjun Lin, Deye Wu, Yuan Zhang, Yibo Wang, Hui Jiang, Suihe Li, Hongxiang Wang, Xianzhen Lu, Zhaoping Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing100083 China Institute of Applied Physics and Computational Mathematics Beijing100088 China Software Center for High Performance Numerical Simulation Chinese Academy of Engineering Physics Beijing100088 China Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China

Fe-based metallic glasses (MGs) have been extensively investigated due to their unique properties, especially the outstanding soft-magnetic properties. However, conventional design of soft-magnetic Fe-based MGs is heavily relied on "trial and error" experiments, and thus difficult to balance the saturation flux density (Bs) and thermal stability due to the strong interplay between the glass formation and magnetic interaction. Herein, we report an eXtreme Gradient Boosting (XGBoost) machine-learning (ML) model for developing advanced Fe-based MGs with a decent combination of Bs and thermal stability. While it is an attempt to apply ML for exploring soft-magnetic property and thermal stability, the developed XGBoost model based on the intrinsic elemental properties (i.e., atomic size and electronegativity) can well predict Bs and Tx (the onset crystallization temperature) with an accuracy of 93.0% and 94.3%, respectively. More importantly, we derived the key features that primarily dictate Bs and Tx of Fe-based MGs from the ML model, which enables the revelation of the physical origins underlying the high Bs and thermal stability. As a proof of concept, several Fe-based MGs with high Tx (>800 K) and high Bs (>1.4 T) were successfully developed in terms of the ML model. This work demonstrates that the XGBoost ML approach is interpretable and feasible in the extraction of decisive parameters for properties of Fe-based magnetic MGs, which might allow us to efficiently design high-performance glassy materials. © 2020, The Author(s).

关键词： Thermodynamic stability