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Laser Powder Bed Fusion of Beta-Type Titanium Alloys for Biomedical Application:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 17-28页

作者： Xuan Luo Chao Yang Dongdong Li lai-Chang Zhang State Key Laboratory of Materials Processing and Die&Mould technology Huazhong University of Science and TechnologyWuhan430074China National engineering Research Center of Near-Net-Shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou510640China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing ofβ-type titanium alloy is expected to replace Ti-6Al-4V alloy in the field of orthopedic implantation because of their low elastic modulus,excellent corrosion resistance,and *** briefly introducing the laser powder bed fusion(LPBF)process and physical phenomena,this paper reviews the recent progresses in LPBF-edβ-type Ti *** strategies to strengthening and tougheningβ-type Ti alloys are critically *** is followed by the processing routes employed to achieve to low modulus for orthopedic applications,especially a new methodology for tailoring crystallographic orientation called multi-track coupled directional *** effect of processing and compositions on performance metrics ofβ-type Ti alloys included corrosion behavior,and biocompatibility is *** the end,challenges in additive manufacturing ofβ-type Ti alloys in future are highlighted,with the aim to ensue clinical application of LPBF-edβ-type Ti alloys.

关键词： β-type Ti alloys Laser powder bed fusion mechanical properties Elastic modulus Biocompatibility

Discrete Boltzmann model with split collision for nonequilibrium reactive flows

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Communications in Theoretical Physics 2024年第8期76卷 166-188页

作者： Chuandong Lin Kai H Luo Huilin lai Sino-French Institute of Nuclear engineering and technology Sun Yat-sen University Key Laboratory for Thermal science and Power engineering of Ministry of Education Department of Energy and Power Engineering Tsinghua University Department of mechanical engineering National University of Singapore Department of mechanical engineering University College London school of Mathematics and Statistics Key Laboratory of Analytical Mathematics and Applications (Ministry of Education) Fujian Key Laboratory of Analytical Mathematics and Applications (FJKLAMA) Center for Applied Mathematics of Fujian Province (FJNU) Fujian Normal University

A multi-relaxation-time discrete Boltzmann model(DBM) with split collision is proposed for both subsonic and supersonic compressible reacting flows, where chemical reactions take place among various components. The physical model is based on a unified set of discrete Boltzmann equations that describes the evolution of each chemical species with adjustable acceleration, specific heat ratio, and Prandtl number. On the right-hand side of discrete Boltzmann equations, the collision,force, and reaction terms denote the change rates of distribution functions due to self-and crosscollisions, external forces, and chemical reactions, respectively. The source terms can be calculated in three ways, among which the matrix inversion method possesses the highest physical accuracy and computational efficiency. Through Chapman–Enskog analysis, it is proved that the DBM is consistent with the reactive Navier–Stokes equations, Fick's law and the Stefan–Maxwell diffusion equation in the hydrodynamic limit. Compared with the one-step-relaxation model, the split collision model offers a detailed and precise description of hydrodynamic, thermodynamic, and chemical nonequilibrium effects. Finally, the model is validated by six benchmarks, including multicomponent diffusion, mixture in the force field, Kelvin–Helmholtz instability, flame at constant pressure, opposing chemical reaction, and steady detonation.

关键词： detonation discrete Boltzmann method nonequilibrium effect reactive flow

Dynamics and vibration reduction performance of asymmetric tristable nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 389-406页

作者： Hongyan CHEN Youcheng ZENG Hu DING Siukai lai Liqun CHEN school of mechanical engineering University of Science and Technology BeijingBeijing 100083China Shanghai Key Laboratory of Mechanics in Energy engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Department of Civil and Environmental engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

With its complex nonlinear dynamic behavior,the tristable system has shown excellent performance in areas such as energy harvesting and vibration suppression,and has attracted a lot of *** this paper,an asymmetric tristable design is proposed to improve the vibration suppression efficiency of nonlinear energy sinks(NESs)for the first *** proposed asymmetric tristable NES(ATNES)is composed of a pair of oblique springs and a vertical ***,the three stable states,symmetric and asymmetric,can be achieved by the adjustment of the distance and stiffness asymmetry of the oblique *** governing equations of a linear oscillator(LO)coupled with the ATNES are *** approximate analytical solution to the coupled system is obtained by the harmonic balance method(HBM)and verified *** vibration suppression efficiency of three types of ATNES is *** results show that the asymmetric design can improve the efficiency of vibration reduction through comparing the chaotic motion of the NES oscillator between asymmetric steady *** addition,compared with the symmetrical tristable NES(TNES),the ATNES can effectively control smaller structural *** other words,the ATNES can effectively solve the threshold problem of TNES failure to weak ***,this paper reveals the vibration reduction mechanism of the ATNES,and provides a pathway to expand the effective excitation amplitude range of the NES.

关键词： asymmetric nonlinear energy sink(NES) tristable vibration control po-tential barrier

mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin Xue Chao Zheng Fu-qiang lai Xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

CLASSIFICATION OF GEAR FAULTS USING HIGHER-ORDER STATISTICS AND SUPPORT VECTOR MACHINES

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Chinese Journal of mechanical engineering 2002年第3期15卷 243-247页

作者： lai Wuxing Zhang Guicai Shi Tielin Yang Shuzischool of mechanical science and engineering, Huazhong university of science and technology,Wuhan 430074, china school of mechanical science and engineering Huazhong University of Science and Technology Wuhan 430074

Gears alternately mesh and detach in driving process, and then workingconditions of gears are alternately changing, so they are easy to be spalled and worn. But becauseof the effect of additive gaussian measurement noises, the signal-to-noises ratio is low; theirfault features are difficult to extract. This study aims to propose an approach of gear faultsclassification, using the cumulants and support vector machines. The cumulants can eliminate theadditive gaussian noises, boost the signal-to-noises ratio. Generalisation of support vectormachines as classifier, which is employed structural risk minimisation principle, is superior tothat of conventional neural networks, which is employed traditional empirical risk minimisationprinciple. Support vector machines as the classifier, and the third and fourth order cumulants asinput, gears faults are successfully recognized. The experimental results show that the method offault classification combining cumulants with support vector machines is very effective.

关键词： Support vector machine Gear Fault diagnosis Cumulant Featureextraction

Component Based Dynamic Reconfigurable Test System

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武汉理工大学学报 2006年第S2期28卷 651-655页

作者： lai Hong HE Lingsong ZHANG Dengpan (school of mechanical science and engineering,Huazhong university of science and technology,Wuhan 430074,china school of mechanical science and engineering Huazhong University of Science and TechnologyWuhan 430074China

In this paper,a novel component based framework of test system is presented for the new requirements of dynamic changes of test functions and reconfiguration of test *** complexity of dynamic reconfiguration arises from the scale, redirection,extensibility and interconnection of components in test *** paper is started by discussing the component assem- bly based framework which provide the open platform to the deploy of companents and then the script interpreter model is introduced to dynamically create the components and build the test system by analyzing XML based information of test system.A pipeline mod- el is presented to provide the data channels and behavior reflection among the ***,a dynamic reconfigurable test system is implemented on the basis of COM and applied in the remote test and control system of CNC machine.

关键词： dynamic reconfiguration test system component based software development CNC machine

Metallurgy and Solidification Microstructure Control of Fusion-Based Additive Manufacturing Fabricated Metallic Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 29-53页

作者： Qiang Li Xing-Ran Li Bai-Xin Dong Xiao-Long Zhang Shi-Li Shu Feng Qiu lai-Chang Zhang Zhi-Hui Zhang Key Laboratory of Bionic engineering(Ministry of Education) and College of Bionic Science and EngineeringJilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China school of mechanical and Aerospace engineering Jilin UniversityChangchun130025China school of engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

The metal-based additive manufacturing(AM),also referred to as metal 3D printing,has drawn particular interest because it enables direct creation,aided by computationally-directed path design,of intricate components with site-specific compositions and geometrical requirements as well as low buy-to-fly *** the last two decades,the objective of this revolutionary technology has been shifting from only“rapid prototyping”to advanced manufacturing of special high-end products or devices,which,in many aspects,outperform conventional manufacturing *** fusion-based AM,significant progress has been achieved in understanding the processing window of macroscopic scales,non-equilibrium metallurgy of mesoscale scales,and grain evolution of microscopic *** the versatile capacity of AM facilitates new avenues for discovering advanced materials and structures,their potential has still not been fully *** the unique non-equilibrium solidification during the AM process,coarse columnar grains with strong textures are usually developed along the build direction,which downgrades the mechanical *** push the limits of this digital manufacturing,this review attempts to provide in-depth and comprehensive overviews of the recent progress in understanding the evolution and control of the as-built microstructure that has been made recently and the challenges encountered during the AM process.

关键词： Additive manufacturing Temperature field Microstructure control Nanoparticles Functionally graded materials

Extending the solid solution range of sodium ferric pyrophosphate:Off‐stoichiometric Na_(3)Fe(2.5)(P_(2)O_(7))_(2)as a novel cathode for sodium‐ion batteries

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Carbon Energy 2024年第4期6卷 128-139页

作者： Xiang jun Pu Kunran Yang Zibing Pan Chunhua Song Yangyang lai Renjie Li Zheng‐Long Xu Zhongxue Chen Yuliang Cao Hubei Key Laboratory of Electrochemical Power Sources College of Chemistry and Molecular SciencesWuhan UniversityWuhanChina Key Laboratory of Hydraulic Machinery Transients Ministry of EducationSchool of Power and Mechanical EngineeringWuhan UniversityWuhanChina school of Chemistry and Chemical engineering Jiangsu University of TechnologyChangzhouJiangsuChina Zonergy Corporation ZigongSichuanChina Department of Industrial and Systems engineering The Hong Kong Polytechnic UniversityHung HomHong Kong SARChina

Iron‐based pyrophosphates are attractive cathodes for sodium‐ion batteries due to their large framework,cost‐effectiveness,and high energy ***,the understanding of the crystal structure is scarce and only a limited candidates have been reported so *** this work,we found for the first time that a continuous solid solution,Na_(4−α)Fe_(2+α)_(2)(P_(2)O_(7))_(2)(0≤α≤1,could be obtained by mutual substitution of cations at center‐symmetric Na3 and Na4 sites while keeping the crystal building blocks of anionic P_(2)O_(7) *** particular,a novel off‐stoichiometric Na_(3)Fe(2.5)(P_(2)O_(7))_(2)is thus proposed,and its structure,energy storage mechanism,and electrochemical performance are extensively investigated to unveil the structure–function *** as‐prepared off‐stoichiometric electrode delivers appealing performance with a reversible discharge capacity of 83 mAh g^(−1),a working voltage of 2.9 V(***^(+)/Na),the retention of 89.2%of the initial capacity after 500 cycles,and enhanced rate capability of 51 mAh g^(−1)at a current density of 1600 mA g^(−1).This research shows that sodium ferric pyrophosphate could form extended solid solution composition and promising phase is concealed in the range of Na_(4−α)Fe_(2+α)_(2)(P_(2)O_(7))_(2),offering more chances for exploration of new cathode materials for the construction of high‐performance SIBs.

关键词： extending solid‐solution range off‐stoichiometric Na_(3)Fe_(2.5)(P_(2)O_(7))_(2) sodium‐ion batteries structure-function relationship

Enhanced thermoelectric performance enabled by compositing ZrO_(2)in n-type SiGe alloy with low thermal conductivity

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Rare Metals 2024年第3期43卷 1167-1176页

作者： Meng-Fei Wang Hua-Jun lai Ji-Sheng Liang Jun-Liang Chen Wang-Yang Ding Qi Zhou Ying Peng Cheng-Yan Liu Lei Miao Guangxi Key Laboratory for Relativity Astrophysics State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite StructuresSchool of Physical Science and TechnologyGuangxi UniversityNanning530004China Guangxi Academy of sciences Nanning530007China Key Laboratory of Information Material Engineering Research Center of Electronic Information Materials and DevicesGuilin University of Electronic TechnologyMinistry of EducationGuilin541004China Guangxi Key Laboratory of Precision Navigation technology and Application School of Information and CommunicationGuilin University of Electronic TechnologyGuilin541004China

SiGe-based thermoelectric(TE)materials have gained increasing interests due to their low maintenance costs,environmental friendliness and long ***,the intrinsically high thermal conductivity of Si-based materials also results in poor TE *** this investigation,a zirconia(ZrO_(2))composite strategy was applied to an n-type SiGe alloy,tremendously elevating its TE *** mechanical alloying and spark plasma sintering(SPS)processes,the ZrO_(2)induced the formation of nanopores in the SiGe matrix via phosphorus ***,such increase in porosity enhanced the phonon scattering and dramatically suppressed lattice thermal conductivity,from 2.83 to 1.59 W·m^(-1)·K^(-1)at 873 ***,reduced phosphorus doping led to an increase in Seebeck coefficients and a relatively minor decrease in electrical conductivity,The power factor didn't deteriorate significantly,either,as its maximum of~3.43 mW·m^(-1-)K^(-2)was achieved at 873 K with(Si_(0.8)Ge_(0.2))_(0.097)P_(0.03)(ZrO_(2))_(0.003).In short,a peak figure of merit(ZT)of~1.27 at 873 K and an average ZT~0.7 from 323 to 873 K were *** study demonstrates that the electrical and thermal transportation of SiGe material can be synergistically tuned by compositing ZrO_(2),illustrating a novel strategy to optimize the TE properties of bulk materials.

关键词： Thermoelectric SiGe alloy ZrO2 composting P element adsorption nanopores