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porous FeAl alloys via powder sintering:Phase transformation,microstructure and aqueous corrosion behavior

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Journal of Materials Science & Technology 2021年第27期86卷 64-69页

作者： Gang Chen Klaus-Dieter Liss Chao Chen Yuehui He Xuanhui Qu Peng Cao Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing100083PR China Materials and Engineering Science Program Guangdong Technion-Israel Institute of TechnologyShantouGuangdong515063PR China Technion-Israel Institute of Technology Haifa32000Israel School of Mechanical MaterialsMechatronic and Biomedical EngineeringFaculty of Engineering&Information SciencesUniversity of WollongongWollongongNSW2522Australia State Key Laboratory for Powder Metallurgy Central South UniversityChangsha410083PR China Department of Chemical and Materials Engineering The University of AucklandPrivate Bag 92019Auckland1142New Zealand MacDiarmid Institute of Advanced Materials and Nanotechnology Victoria University of WellingtonPO Box 600Wellington6140New Zealand

This study investigates the phase transformation and microstructure of porous Fe Al parts sintered from elemental powder mixtures using in-situ neutron diffraction and in-situ thermal dilatometry.A single B2 structured Fe Al phase was determined in the sintered Fe Al alloy.The combined effects of the Kirkendall porosity,transient liquid phase,and phase transformations associated with powder sintering all contribute to the swelling phenomenon of the final sintered part.The aqueous corrosion test indicates that the corrosion products include iron oxides in the porous Fe Al parts.The accumulation of corrosion products blocks the pore channel and decreases pore size and permeability over the soaking time.

关键词： Powder sintering Intermetallic porous Corrosion Neutron diffraction

porous nitrogen-doped carbon/MnO coaxial nanotubes as an efficient sulfur host for lithium sulfur batteries

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Nano Research 2019年第1期12卷 205-210页

作者： Chao Lin Longbing Qu Jiantao Li Zhengyang Cai Haoyun Liu Pan He Xu Xu Liqiang Mai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyLuoshi Road 122Wuhan 430070China Department of Mechanical Engineering The University of MelbourneVictoria 3010Australia

As a promising candidate for next generation energy storage devices, lithium sulfur (Li-S) batteries still confrant rapid capacity degradation and low rate capability. Herein, we report a well-architected porous nitrogen-doped carbon/MnO coaxial nanotubes (MnO@PNC) as an efficient sulfur host material. The host shows excellent electron conductivity, sufficient ion transport channels and strong adsorption capability for the polysulfides, resulting from the abundant nitrogen-doped sites and pores as well as MnO in the carbon shell of MnO@PNC. The MnO@PNC-S composite electrode with a sulfur content of 75 wt.% deliveries a specific capacity of 802 mAh·g^-1 at a high rate of 5.0C and outstanding cycling stability with a capacity retention of 82% after 520 cycles at 1.0C.

关键词： nitrogen doping porous MnO carbon nanotubes sulfur batteries

Research progress and clinical translation of three-dimensional printed porous tantalum in orthopaedics

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Biomaterials Translational 2023年第3期4卷 166-179页

作者： Jiawei Ying Haiyu Yu Liangliang Cheng Junlei Li Bin Wu Liqun Song Pinqiao Yi Haiyao Wang Lingpeng Liu Dewei Zhao Department of Orthopaedics Affiliated Zhongshan Hospital of Dalian UniversityDalianLiaoning ProvinceChina

With continuous developments in additive manufacturing technology, tantalum (Ta) metal has been manufactured into orthopaedic implants with a variety of forms, properties and uses by three-dimensional printing. Based on extensive research in recent years, the design, processing and performance aspects of this new orthopaedic implant material have been greatly improved. Besides the bionic porous structure and mechanical characteristics that are similar to human bone tissue, porous tantalum is considered to be a viable bone repair material due to its outstanding corrosion resistance, biocompatibility, bone integration and bone conductivity. Numerous in vitro, in vivo, and clinical studies have been carried out in order to analyse the safety and efficacy of these implants in orthopaedic applications. This study reviews the most recent advances in manufacturing, characteristics and clinical application of porous tantalum materials.

关键词： 3D printed additive manufacturing orthopaedic implant porous tantalum

porous Structure Analysis of the Packed Beds in a High-Temperature Reactor Pebble Bed Modules Heat Transfer Test Facility

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Chinese Physics Letters 2013年第2期30卷 65-68页

作者：任成杨星团孙艳飞 Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education Institute of Nuclear and New Energy TechnologyTsinghua UniversityBeijing 102201

We analyse the porous structure of the packed beds in the heat transfer test facility built for high temperature gas cooled reactors from several aspects,such as oscillatory porosity,average porosity,thickness effect,coordination number and contact angle.An understanding and comparison of the porous structure of the facility bed and the real reactor core are developed to make recommendations for the design and analysis of the heat transfer test facility.The results show that there is very little difference between the porous characteristics of the two packed beds of spheres.

关键词： porosity packed porous

Application of a novel porous tantalum implant in rabbit anterior lumbar spine fusion model:in vitro and in vivo experiments

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Chinese Medical Journal 2019年第1期132卷 51-62页

作者： Ming Lu Song Xu Zi-Xiong Lei Dong LU Wei Cao Marko Huttula Chang-He Hou Shao-Hua Du Wei Chen Shuang-Wu Dai Hao-Miao Li Da-Di Jin Department of Orthopedic The Third Affiliated Hospital of Southern Medical UniversityGuangzhouGuangdong 510630China Academy of Orthopaedics of Guangdong Province GuangzhouGuangdong 510630China Department of Arthroplasty Nanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China Ning Xia Orient Tantalum Industry Co.Ltd ShizuishanNingxia 753000China Department of Physics University of OuluOulu FIN-90014Finland

Background Some porous materials have been developed to enhance biologic fusion of the implants to bone in spine fusion surgeries.However,there are several inherent limitations.In this study,a novel biomedical porous tantalum was applied to in vitro and in vivo experiments to test its biocompatibility and osteocompatibility.Methods Bone marrow-derived mesenchymal stem cells (BMSCs) were cultured on porous tantalum implant.Scanning electron microscope (SEM) and Cell Counting Kit-8 assay were used to evaluate the cell toxicity and biocompatibility.Twenty-four rabbits were performed discectomy only (control group),discectomy with autologous bone implanted (autograft group),and discectomy with porous tantalum implanted (tantalum group) at 3 levels:L3–L4,L4–L5,and L5–L6 in random order.All the 24 rabbits were randomly sacrificed at the different post-operative times (2,4,6,and 12 months;n = 6 at each time point).Histologic examination and micro-computed tomography scans were done to evaluate the fusion process.Comparison of fusion index scores between groups was analyzed using one-way analysis of variance.Other comparisons of numerical variables between groups were made by Student t test.Results All rabbits survived and recovered without any symptoms of nerve injury.Radiographic fusion index scores at 12 months post-operatively between autograft and tantalum groups showed no significant difference (2.89 ± 0.32 vs.2.83 ± 0.38, F= 244.60, P = 0.709).Cell Counting Kit-8 assay showed no significant difference of absorbance values between the leaching liquor group and control group (1.25 ± 0.06 vs.1.23 ± 0.04, t = –0.644, P = 0.545),which indicated the BMSC proliferation without toxicity.SEM images showed that these cells had irregular shapes with long spindles adhered to the surface of tantalum implant.No implant degradation,wear debris,or osteolysis was observed.Histologic results showed solid fusion in the porous tantalum and autologous bone implanted intervertebral spaces.Conclusion This novel porous tantalum implant s

关键词： porous tantalum anterior lumbar interbody fusion bone ingrowth chemical vapor deposition three-dimensional knitted framework

Quantitative criteria for identifying main flow channels in complex porous media

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Petroleum Exploration and Development 2019年第5期46卷 998-1005页

作者： LI Xizhe LU Detang LUO Ruilan SUN Yuping SHEN Weijun HU Yong LIU Xiaohua QI Yadong GUAN Chunxiao GUO Hui PetroChina Research Institute of Petroleum Exploration&Development Langfang 065007China Department of Modern Mechanics University of Science and Technology of ChinaHefei 230026China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

To identify the type of main flow channels of complex porous media in oil and gas reservoirs,the"main flow channel index"is defined as the ratio of comprehensive permeability obtained from well test to matrix permeability obtained from core analysis or well logging.Meanwhile,a mathematical model is established based on equivalent flow assumption,the classification method for main flow channels is put forward,and quantitative characterization of main flow channels is realized.The method has been verified by analysis of typical gas reservoirs.The study results show that the"main flow channel index"can quantitatively classify types of flow channels.If the index is less than 3,the matrix pore is the main flow channel;if the index is between 3 and 20,the fracture is the main flow channel and the matrix pore acts as the supplement one;if the index is more than 20,the fracture is the only seepage channel.The dynamic analysis of typical gas reservoirs shows that the"main flow channel index"can be used to identify the type of flow channel in complex porous media,guiding the classified development of gas reservoirs,and avoiding development risk.

关键词： porous media matrix pore fracture flow channels main flow channel index quantitative identification criteria

Facile Synthesis of porous Zn–Sn–O Nanocubes and Their Electrochemical Performances

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Nano-Micro Letters 2016年第2期8卷 174-181页

作者： Bo Li Xiaomin Li Jiantao Zai Xuefeng Qian School of Chemistry and Chemical Engineering and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

porous Zn–Sn–O nanocubes with a uniform size were synthesized through a facile aqueous solution route combined with subsequent thermal treatment. The chemical composition, morphology, and microstructure of Zn–Sn–O nanocubes, which have significant effects on the lithium storage performances, were easily tuned by adjusting the calcination temperature in preparation processes of ZnSn(OH)6solid nanocubes. Further studies revealed that porous Zn–Sn–O nanocubes prepared at 600 °C exhibited a good rate capability and a high reversible capacity of 700 m Ah g^(-1)at a current density of 200 m Ag^(-1)after 50 cycles, which may be a great potential as anode materials in Lithium-ion batteries.

关键词： Zn–Sn–O Nanocubes porous Lithium-ion batteries

Numerical simulation on heat transfer inside rotating porous disk subjected to local heat flux

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Science China(Technological Sciences) 2013年第7期56卷 1657-1666页

作者： ZHU XingDan ZHANG JingZhou TAN XiaoMing College of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics

Numerical simulation was carried out to study the centrifugally-driven flow and heat transfer inside rotating metallic porous disk subjected to local heat flux. The effects of rotational speed, solid thermal conductivity and porosity on heat transfer were analyzed. The thermal transport coefficient, defined as the ratio of local heat flux to maximum temperature difference on the disk, was introduced to evaluate the thermal transport capacity in rotating porous disk. For convenience, the conjugation between convective heat transfer inside the rotating porous disk and convective heat transfer over the rotating disk surface was decoupled in the present study. Firstly, the convective heat transfer over the free rotating disk surface was investigated indi-vidually to determine the heat transfer coefficient over the disk surface to the ambient air. Then the convective heat transfer over a rotating disk surface was treated as the thermal boundary condition for the computation of convective heat transfer in-side rotating porous disk. Under the present research conditions, the results show that the centrifugally-driven flow is enhanced significantly with the increase of rotational speed. Consequently, the maximum temperature on the disk surface is decreased and the temperature distribution tends to be uniform. The thermal transport capacity in rotating porous disk is also enhanced with the increase of solid thermal conductivity or the decrease of solid porosity. In the rotating porous disk, the solid phase heat transfer is clearly the dominant mode of heat transport and the fluid phase makes an incremental contribution to the total heat transfer.

关键词： local heat flux rotating disk porous medium centrifugally-driven flow numerical simulation

On the role of the microstructure in the deformation of porous solids

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npj Computational Materials 2022年第1期8卷 1443-1449页

作者： Sansit Patnaik Mehdi Jokar Wei Ding Fabio Semperlotti Ray W.Herrick Laboratories School of Mechanical EngineeringPurdue University West LafayetteWest LafayetteIN47907USA

This study explores the role that the microstructure plays in determining the macroscopic static response of porous elastic continua and exposes the occurrence of position-dependent nonlocal effects that are strictly correlated to the configuration of the microstructure.Then,a nonlocal continuum theory based on variable-order fractional calculus is developed in order to accurately capture the complex spatially distributed nonlocal response.The remarkable potential of the fractional approach is illustrated by simulating the nonlinear thermoelastic response of porous beams.The performance,evaluated both in terms of accuracy and computational efficiency,is directly contrasted with high-fidelity finite element models that fully resolve the pores’geometry.Results indicate that the reduced-order representation of the porous microstructure,captured by the synthetic variable-order parameter,offers a robust and accurate representation of the multiscale material architecture that largely outperforms classical approaches based on the concept of average porosity.

关键词： porous fractional solids