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Journal of Materials Science & Technology 2021年第24期83卷 18-33页

作者： y.M.Ren X.Lin H.O.yang H.Tan J.Chen Z.y.Jian J.q.Li W.D.huang School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an710021China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China

Laser additive manufacturing(LAM)technique has unique advantages in producing geometrically complex metallic ***,the poor low-cycle fatigue property(LCF)of LAM parts restricts its widely ***,the microstructural features of a Ti-6 Al-4 V alloy manufactured via high power laser directed energy deposition subjected to low-cycle fatigue loading were *** fatigue loading,the microstructure of the as-deposited parts was found to exhibit a non-homogeneous distribution of columnar prior-βgrains(200-4000μm)at various scanning velocities(300-1500 mm/min)and relatively coarseα-laths(1.0-4.5μm).Under cyclic loading,fatigue microcracks typically initiated within the alignedαphases in the preferred orientation(45°to the loading direction)at the surface of the fatigue *** Ti-6 Al-4 V exhibited a single straight dislocation character at low strain amplitudes(1.1%).In addition,dislocation substructure features,such as dislocation walls,stacking faults,and dislocation networks,were also *** findings may provide opportunities to understand the fatigue failure mechanism of additive manufactured titanium parts.

关键词： Laser additive manufacturing Directed energy deposition Titanium alloy Low-cycle fatigue Microstructure

Irradiation-induced homogeneous plasticity in amorphous/amorphous nanolaminates

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Journal of Materials Science & Technology 2020年第22期54卷 70-77页

作者： L.huang Z.q.Chen P.huang X.K.Meng F.Wang State Key Laboratory for Mechanical Behavior of Material School of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an710049China Institute of Materials Engineering National Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi'an Jiaotong UniversityXi'an710049China

Achieving homogeneous plastic deformation in metallic glasses is a long-standing goal yet to be solved in materials science. Here we investigate the effect of ion irradiation on the plastic deformation behavior of ZrCu/ZrCuNiAlSi amorphous/amorphous nanolaminates(A/ANLs) via nanoindentation testing. The experimental results indicate a dramatic change in deformation mode from multiple shear banding events to homogeneous compressive deformation before and after ion irradiation on the A/ANLs in the areas underneath the indenter. Ion irradiation-induced changes of both fraction and distribution of free volume inside each constituent layer and interfacial state in the A/ANLs may be responsible for the unusual homogeneous deformation behavior. Our results suggest that the mechanical property of A/ANLs could be modified by tuning both the inner and interfacial structure via ion irradiation.

关键词： Metallic glasses Ion irradiation Plastic deformation Nanolaminates Interface

Dispatchable Region for Active Distribution Networks Using Approximate Second-order Cone Relaxation

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 1999-2007页

作者： Zhigang Li Wenjing huang J.H.Zheng q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

Uncertainty in distributed renewable generation threatens the security of power distribution *** concept of dispatchable region is developed to assess the ability of power systems to accommodate renewable generation at a given operating *** DC and linearized AC power flow equations are typically used to model dispatchable regions for transmission systems,these equations are rarely suitable for distribution *** achieve a suitable trade-off between accuracy and efficiency,this paper proposes a dispatchable region formulation for distribution networks using tight convex *** cone relaxation is adopted to reformulate AC power flow equations,which are then approximated by a polyhedron to improve ***,an efficient adaptive constraint generation algorithm is employed to construct the proposed dispatchable *** studies on distribution systems of various scales validate the computational efficiency and accuracy of the proposed method.

关键词： Dispatchable region distribution system renewable power generation second-order cone relaxation uncertainty

Relaxed Alternating Direction Method of Multipliers for Hedging Communication Packet Loss in Integrated Electrical and Heating System

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Journal of Modern Power Systems and Clean Energy 2020年第5期8卷 874-883页

作者： Xinyu Liang Zhigang Li Wenjing huang q.H.Wu Haibo Zhang School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China IEEE State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Integrated electrical and heating systems(IEHSs)are promising for increasing the flexibility of power systems by exploiting the heat energy storage of *** the recent development of advanced communication technology,distributed optimization is employed in the coordination of IEHSs to meet the practical requirement of information privacy between different system *** studies on distributed optimization algorithms for IEHSs have seldom addressed packet loss during the process of information *** this paper,a distributed paradigm is proposed for coordinating the operation of an IEHS considering communication packet *** relaxed alternating direction method of multipliers(R-ADMM)is derived by applying Peaceman-Rachford splitting to the Lagrangian dual of the primal *** proposed method is tested using several test systems in a lossy communication and transmission *** results indicate the effectiveness and robustness of the proposed R-ADMM algorithm.

关键词： Alternating direction method of multipliers(ADMM) communication failure distributed optimization integrated energy systems packet loss

Pressure Evolution of the Magnetism and Fermi Surface of ybPtBi Probed by a Tunnel Diode Oscillator Based Method

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Chinese Physics Letters 2022年第9期39卷 41-46页

作者： y.E.huang F.Wu A.Wang y.Chen L.Jiao M.Smidman H.q.yuan Center for Correlated Matter and Department of Physics Zhejiang UniversityHangzhou 310058China Zhejiang Province Key Laboratory of quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310058China State Key Laboratory of Silicon Materials Zhejiang UniversityHangzhou 310058China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

A central research topic in condensed matter physics is the understanding of the evolution of various phases and phase transitions under different tuning parameters such as temperature, magnetic field and pressure. To explore the pressure-induced evolution of the magnetism and Fermi surface of the heavy fermion antiferromagnet yb Pt Bi, we performed tunnel diode oscillator based measurements under pressure at low temperatures in high magnetic fields. Our results reveal that the magnetic order strengthens and the Fermi surface shrinks as the pressure increases, which are consistent with typical observations for yb-based heavy fermion compounds. In addition, an anomalous change in the quantum oscillation amplitudes is observed above 1.5 GPa, and determining the origin requires further study.

关键词： Fermi Probe oscillation

DyNAMIC ANALySIS OF ARREST OF BUCKLE PROPAGATION ON A BEAM ON A NONLINEAR ELASTIC FOUNDATION By FEM

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Acta Mechanica Solida Sinica 1997年第1期10卷 28-30,32-35页

作者： Zou, SZ huang, yy Liu, ZH qian, q SHASHI UNIV SHASHI 434000PEOPLES R CHINA HUAZHONG UNIV SCI & TECHNOL WUHAN 430074PEOPLES R CHINA ACAD SINICA INST MECHBEIJING 100080PEOPLES R CHINA

Based on the dynamic governing equation of propagating buckle on a beam on a nonlinear elastic foundation, this paper deals with an important problem of buckle arrest by combining the FEM with a time integration technique. A new conclusion completely different from that by the quasi-static analysis about the buckle arrestor design is drawn. This shows that the inertia of the beam cannot be ignored in the analysis under consideration, especially when the buckle propagation is suddenly stopped by the arrestors.

关键词： buckle propagation arrest of buckle beam on a nonlinear foundation finite element method

SIMULATION OF THE STOCHASTIC DAMAGE EVOLUTION PROCESS UNDER LOW CyCLE FATIGUE By THE FINITE ELEMENT METHOD

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Acta Mechanica Solida Sinica 1996年第3期9卷 274-281页

作者： huang, ZZ Gao, q Dai, Zy qian, R SW JIAOTONG UNIV INST APPL MECHCHENGDU 610031PEOPLES R CHINA

A numerical simulation of stochastic damage evolution process in the condition of low cycle fatigue loading is discussed. The relations between damage variables and micro-cracks are obtained by means of the micro-mechanics model of the representative volume element proposed by Lemaitre and Dufailly([10]). The stochastic Initial damage values are introduced in consideration of the inherent micro-defects In materials. The model combined with a finite element method is applied to simulate the damage evolution process under low cycle fatigue loading. The micro-cracks on the sur face of a specimen of 19Mn6 alloy steel are measured with a replica technique. The numerical results show that the nonhomogeneity of damage and the localization of the fatigue failure are well shown by the proposed simulations, and the fatigue lives are reasonably predicted.

关键词： stochastic damage micro-mechanics model low cycle fatigue numerical simulation

Constructing two-scale network microstructure with nano-Ti5Si3 for superhigh creep resistance

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Journal of Materials Science & Technology 2019年第8期35卷 1532-1542页

作者： y.Jiao L.J.huang S.L.Wei H.X.Peng q.An S.Jiang L.Geng State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001 China Center of Analysis and Measurement Harbin Institute of TechnologyHarbin 150001 China Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridge MA02139 USA Institute for Composites Science Innovation (InCSI) School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027 China

The improvement of mechanical properties must be achieved by designing and constructing more suitable microstructure,such as hierarchical *** order to significantly enhance the creep resistance of titanium matrix composites(TMCs),two-scale network microstructure was constructed including the first-scale network(y powder metallurgy and in-situ *** results showed that the creep rate of the composite was remarkably reduced by an order of magnitude compared with the Ti6Al4V alloy at 550℃,600℃,650℃ under the stresses between 100 MPa and 350 ***,the rupture time of the composite was increased by 20 times,compared with that of the Ti6Al4 Valloy at 550℃/300 *** superior creep resistance could be attributed to the hierarchical *** micro-TiBw reinforcement in the first-scale network boundary contributed to creep resistance primarily by blocking grain boundary sliding,while the nano-Ti5Si3 particle in the second-scale network boundary mainly by hindering phase boundary *** addition,the nano-Ti5Si3 particle was dissolved,and precipitated with smaller size than the primary *** phenomenon was attributed to Si element diffusion under high temperature and external stress,which could further continuously enhance the creep ***,the creep rate during steady-state stage was significantly decreased,which manifested superior creep resistance of the composite.

关键词： Titanium matrix composite Two-scale network microstructure Nano-Ti5Si3 Creep Powder metallurgy

First-Principles Study of the Influence of Lattice Misfit on the Behavior and the Ductility Effect of Hafnium in Ni-Ni3AI System

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Acta Metallurgica Sinica(English Letters) 2014年第1期27卷 87-94页

作者： y. Wu J. Guo W. Zhang X. Ma q. Zhang J. Hou R. huang X. Liu Institute of Molecular Engineering and Applied Chemistry Anhui University of Technology Ma'anshan 243002 China Shenyang National Laboratory for Materials Science Instituteof Metal Research Chinese Academy of SciencesShenyang 110016 China College of Physics Science and Technology Shenyang NormalUniversity Huanghe Street 253 Shengyang 110034 China School of Materials Science and Engineering Anhui Universityof Technology Ma'anshan 243002 China

Two Ni/Ni3Al-interface-contained cluster models with/without lattice misfit are studied by first-principles method to clarify the debates about the segregation behaviors of Hafnium （Hf） and explore the influence of lattice misfit on the ductility effect of Hr. It is found that though Hf prefers to substitute A1 rather than Ni in Ni3A1 phase within most of the investigated misfit range, its stronger preferring to Ni phase than NiaA1 phase makes it impossible to go into Ni3A1 phase to occupy A1 site in Ni-Ni3A1 alloys. Bond order analysis in Hf-free case shows that lattice misfit has different effects on the Griffith work of interfacial cleavage 27int/E and the maximum theoretical shear stress Zmax of Ni and Ni3A1, contributing to the existence of anomalous strength-temperature phenomena in NiaA1 alloys. However, the addition of Hf will make the 27int/E （or Zmax） of both Ni3A1 and Ni decrease （or increase） with lattice misfit, indicating that the addition of Hf may make the anomalous strength-temperature relationship in Ni3A1 region disappear locally.

关键词： Hafnium Lattice misfit Segregation Ductility

Experimental analysis on strength and failure modes of wood beam-column connections

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Frontiers of Structural and Civil Engineering 2014年第3期8卷 260-269页

作者： Zhenhua huang Sheldon q SHI Liping CAI Deportment of Engineering Technology University of North Texas Denton TX 76210 USA

This research experimentally examined the strength, failure modes, and behaviors of dowel-bearing and fiber-bearing wood beam-column connections and explored the effects of cyclic loading on the strength, failure modes, and behaviors of those connections. Base on limited numbers of exploratory laboratory tests （6 preliminary tests in total）, the authors observed that the typical bolted connection （dowel-bearing type wood beam-column connection with fiber- bearing surfaces） showed good behavior （large peak moment） under the monotonic loads, and the tenon joint connection （fiber-bearing wood beam-column connection） showed good behavior under cyclic loads. The cyclic property of loading reduced the strength of the dowel-bearing type wood beam-column connections, but increased the strength of fiber- bearing type wood beam-column connections. More importantly, the authors identified a possible location of safety concern in current national design specifications （NDS） standards for the typical bolted connection （dowel-bearing connection with fiber bearing surface） under cyclic loading because the tested value was smaller than the NDS calculated value. But, because of the small amount of tests conducted, no final conclusion can be drawn based on those preliminary observations yet. A large number of repetitive laboratory tests should be conducted.

关键词： wood connection dowel-beating fiber-bearing