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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1780-1787页

作者： Liang Lan Ruyi xin xinyuan Jin Shuang Gao bo he School of Material Engineering Shanghai University of Engineering ScienceShanghai 201620China Research Center of High-temperature Alloy Precision Forming Shanghai University of Engineering ScienceShanghai 201620China

Laser shock peening(LSP)is an attractive post-processing method to tailor surface microstructure and enhance mechanical performances of additive manufactured(AM)components.The effects of multiple LSP treatments on the microstructure and mechanical properties of Ti-6Al-4V part produced by electron beam melting(EBM),as a mature AM process,were studied in this work.Microstructure,surface topography,residual stress,and tensile performance of EBM-manufactured Ti-6Al-4V specimens were systematically analyzed subjected to different LSP treatments.The distribution of porosities in EBM sample was assessed via X-ray computed tomography.The results showed that EBM samples with two LSP treatments possessed a lower porosity value of 0.05%compared to the value of 0.08%for the untreated samples.The strength of EBM samples with two LSP treatments was remarkably raised by 12%as compared with the as-built samples.The grains ofαphase were refined in near-surface layer,and a dramatic increase in the depth and magnitude of compressive residual stress(CRS)was achieved in EBM sample with multiple LSP treatments.The grain refinement ofαphase and CRS with larger depth were responsible for the strength enhancement of EBM samples with two LSP treatments.

关键词： additive manufacturing laser shock peening electron beam melting residual stress Ti-6Al-4V alloy mechanical properties

Characterization of a novel fluidic friction-reduction tool used in extended-reach well considering periodic particle-laden jet

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Petroleum Science 2023年第6期20卷 3700-3711页

作者： Lu-bo Tang Xiao-Bin Chen Wei-Wei xin Shao-he Zhang xin-xin Zhang School of Civil Engineering Central South UniversityChangsha410083HunanChina Jiangxi Geological Exploration Bureau for Non-ferrous Metals Nanchang330000JiangxiChina Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring(Central South University) Ministry of EducationChangsha410083HunanChina School of Geosciences and Info-Physics Central South UniversityChangsha410083HunanChina

Fluidic oscillators(FOs)can be used as an efficient fluidic vibration tool to solve high friction problems in extended-reach wells.However,the complex mechanism of FOs makes the design challenging,and the dynamic erosion behavior inside FOs is still unclear.In this paper,new FOs are proposed and the working characteristics under the influence of periodic particle-laden jets are investigated.Firstly,the results reveal the working mechanism of new FOs,showing that the generation of pressure pulses is closely connected with periodic jet switching and the development of vortices.Secondly,the important performance parameters,i.e.,pressure pulse and oscillation frequency,are extensively studied through numerical simulation and experimental verification.It is found that the performance can be optimized by adjusting the tool structure according to different engineering requirements.Finally,the oscillating solid-liquid two-phase flow inside FO is studied.It is demonstrated that the accumulation of particles leads to a significant reduction in performance.The results also reveal five locations that are susceptible to erosion and the erosion behavior of these locations are studied.It has been shown that the periodic jet causes fluctuations in the amount of erosion at the outlet and splitter.This research can provide valuable references for the design and optimization of vibration friction-reduction tools.

关键词： Extended-reach well Fluidic oscillator Vibratory tool Erosion Friction reduction

Effect of Zn addition on microstructure and mechanical properties of Mg-3Y-2Nd-0.5Zr alloy

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China Foundry 2023年第4期20卷 299-306页

作者： Fei-yu he Wen-xin Hu Li-juan Liu Shao-bo Ma Wei he State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou 014030Inner MongoliaChina Baotou Research Institute of Rare Earths Baotou 014030Inner MongoliaChina Technical Center of Steel Union Co. Ltd.of Baotou Steel(Group)Corp.Baotou 014010Inner MongoliaChina

The effect of 0.5wt.%Zn addition on the microstructure and mechanical properties of Mg-3Y-2Nd-0.5Zr(WE32)alloy was investigated.The results indicate that WE32-0.5Zn alloy takes 48 h to reach peak hardness after solid solution treatment at 525℃and aging at 200℃,10 h earlier than WE32 alloy,which implies an accelerated aging precipitation kinetics owing to the addition of 0.5wt.%Zn.A large quantity of finerod and rectangular block-like Zn-Zr precipitates in theα-Mg matrix are formed in the WE32-0.5Zn alloy,and numerous needle-likeβ1phases are distributed at both ends of the Zn-Zr precipitates at peak-aged condition.In peak-aged condition,the ultimate tensile strength considerably increases from 263.2 MPa(WE32)to 309.6 MPa(WE32-0.5Zn),and the elongation dramatically increases from 4.3%(WE32)to 8.9%(WE32-0.5Zn).Theβ’andβ1phases are the main precipitates of the WE32-0.5Zn alloy peak-aged at 200℃.Theβ’andβ1phases easily nucleate at the Zn-Zr precipitates,and theβ1phases are particularly likely to nucleate and grow at the interface between the two ends of the Zn-Zr precipitates,which accelerates aging precipitation kinetics and leads to a shorter time to achieve peak aging.

关键词： Mg-3Y-2Nd-0.5Zr Zn-Zr precipitates microstructure mechanical properties

Solution set calculation of the Sun-perturbed optimal two-impulse trans-lunar orbits using continuation theory

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Astrodynamics 2020年第1期4卷 75-86页

作者： bo-yong he Hong-xin Shen State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an710043China

The solution set of the Sun-perturbed optimal two-impulse trans-lunar orbit is helpful for overall optimization of the lunar exploration mission.A model for computing the two-impulse trans-lunar orbit,which strictly satisfies the boundary constraints,is established.The solution set is computed first with a circular restricted three-body model using a generalized local gradient optimization algorithm and the strategy of design variable initial continuation.By taking the solution set of a circular restricted three-body model as the initial values of the design variables,the Sun-perturbed solution set is calculated based on the dynamic model continuation theory and traversal search methodology.A comparative analysis shows that the fuel cost may be reduced to some extent by considering the Sun’s perturbation and choosing an appropriate transfer window.Moreover,there are several optimal two-impulse trans-lunar methods for supporting a lunar mission to select a scenario with a certain ground measurement and to control the time cost.A fitted linear dependence relationship between the Sun’s befitting phase and the trans-lunar duration could thus provide a reference to select a low-fuel-cost trans-lunar injection window in an engineering project.

关键词： trans-lunar orbit optimization optimal solution set continuation theory Sun-perturbed

GRB 170817A: a short GRB seen off-axis

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Research in Astronomy and Astrophysics 2018年第4期18卷 69-76页

作者： xin-Bo He Pak-Hin Thomas Tam Rong-Feng Shen School of Physics and Astronomy Sun Yat-sen University

The angular distribution of gamma-ray burst（GRB）jets is not yet clear.The observed luminosity of GRB 170817A is the lowest among all known short GRBs,which is best explained by the fact that our line of sight is outside of the jet opening angle,θ_（obs）〉θ_j,whereθ_（obs） is the angle between our line of sight and the jet axis.As inferred by gravitational wave observations,as well as radio and X-ray afterglow modeling of GRB 170817A,it is likely that θ_（obs）~20°–28°.In this work,we quantitatively consider two scenarios of angular energy distribution of GRB ejecta：a top-hat jet and a structured jet with a power law index s.For the top-hat jet model,we get a large θ_j（e.g.,θ_j〉10°）,a rather high local （i.e., z 〈 0.01） short GRB rate ~8–15×10~3 Gpc^（-3）yr~（-1（（estimated to be 90~1850 Gpc^（-3）yr^（-1） in Fong et al.）and an extremely high（on-axis,V（~500 ke V for a typical short GRB）.For the structured jet model,we use θ_（obs） to give limits on s and θ_j for typical on-axis luminosity of a short GRB（e.g.,10^（49）erg s（-1） 1051erg s（-1））,and a low on-axis luminosity case（e.g.,1049erg s（-1））gives more reasonable values of s.The structured jet model is more feasible for GRB170817A than the top-hat jet model due to the rather high local short GRB rate,and the extremely high on-axis E_（peak,0） almost rules out the top-hat jet model.GRB 170817A is likely a low on-axis luminosity GRB（1049erg s（-1））with a structured jet.

关键词： short gamma-ray burst individual（GRB 170817A） — gravitational wave

Localized high-concentration electrolytes for lithium metal batteries:progress and prospect

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1354-1371页

作者： Jia-xin Guo Wen-bo Tang Xiaosong Xiong he Liu Tao Wang Yuping Wu xin-Bing Cheng School of Energy and Environment Southeast UniversityNanjing 211189China School of Chemistry and Materials Science Nanjing University of Information Science and TechnologyNanjing 210044China

With the increasing development of digital devices and electric vehicles,high energy-density rechargeable batteries are strongly required.As one of the most promising anode materials with an ultrahigh specific capacity and extremely low electrode potential,lithium metal is greatly considered an ideal candidate for nextgeneration battery systems.Nevertheless,limited Coulombic efficiency and potential safety risks severely hinder the practical applications of lithium metal batteries due to the inevitable growth of lithium dendrites and poor interface stability.Tremendous efforts have been explored to address these challenges,mainly focusing on the design of novel electrolytes.here,we provide an overview of the recent developments of localized high-concentration electrolytes in lithium metal batteries.Firstly,the solvation structures and physicochemical properties of localized high-concentration electrolytes are analyzed.Then,the developments of localized high-concentration electrolytes to suppress the formation of dendritic lithium,broaden the voltage window of electrolytes,enhance safety,and render low-temperature operation for robust lithium metal batteries are discussed.Lastly,the remaining challenges and further possible research directions for localized highconcentration electrolytes are outlined,which can promisingly render the practical applications of lithium metal batteries.

关键词： high-concentration electrolyte localized high-concentration electrolyte lithium metal battery solid electrolyte interphase dendrite

Synthesis and characterization of superhydrophobic magnesium oxysulfate whiskers

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Particuology 2023年第7期78卷 111-121页

作者： Zhenying Yao Lu Gong Chunmei Zhu xin Lian Bai he Shenghui Tian bo Yui School of Chemistry and Chemical Engineering Chongqing University of Science and TechnologyChongqing401331China Provincial and Ministerial Co-Constructive of Collaborative Innovation Center for MSw Comprehensive Utilization School of Metallurgy and Materials EngineeringChongqing University of Science and TechnologyChongqing401331China

Superhydrophobic materials have attracted much attention for their special wettability.In this study.magnesium oxysulfate(MOS)whiskers were surface modified by vinyltrimethoxysilane(VTMS)and prepared as superhydrophobic materials,which are expected to be widely used in self-cleaning,corro-sion prevention,and oil-water separation.The factors of silane concentration,hydrolysis time,reaction temperature,and reaction time were investigated.The superhydrophobic Mos whiskers were synthe-sized.SEM and XRD turned out that there were no apparent changes in the morphology and crystalli-zation behavior of whiskers before and after modification,while the surface was uniformly coated with a layer of non-crystal material,and the surface of the whiskers employed a chemical bond Si-O-Mg covalently connected.The thermogravimetric analysis ultimately demonstrated that surface modification was beneficial to the improvement of the thermal stability of MoS whiskers.Superhydrophobic MoS whiskers showed good compatibility with organic solvents through oil-water separation experiments,and demonstrated excellent self-cleaning performance.The methodology for the surface treatment of Mos whiskers to prepare superhydrophobic whiskers in this work may be extended for other whiskers or fillers,which may be promising for the preparation of superhydrophobic materials.

关键词： Magnesium oxysulfate whiskers Surface modification Vinyltrimethoxysilane Superhydrophobicity

Numerical simulation of flow characteristics of side-bottom combined blowing in iron bath reactor

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Journal of Iron and Steel Research(International) 2023年第2期30卷 236-248页

作者： Yi-bo he Wen-ke Guo Yi-hong Li Guang-ming Liu xin Cui School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan030024ShanxiChina

A numerical model of an iron bath smelting reduction furnace with side-bottom combined blowing was established to study the influence of blowing arrangements on the stirring effect of the molten pool,and the accuracy of numerical simulation was verified by water model experiment.By comparing the flow field of molten pool with single nozzle,double nozzles(symmetrical and asymmetrical),and four nozzles(symmetrical and asymmetrical),the proportion of dead zone,average turbulent kinetic energy,and mixing time,the results show that asymmetrical bottom blowing is better than symmetrical bottom blowing,and the effect of double nozzles bottom blowing was better than that of four nozzles bottom blowing.The mixing effect is the worst under the condition of single nozzle.When the bottom blowing is asymmetrical with double nozzles,the mixing time is the shortest.Under the condition of double nozzles asymmetrical bottom blowing,when the insertion angle and depth of side lance are larger and deeper,the velocity streamline of molten slag layer is denser and the value is larger;meanwhile,the reflux of molten iron layer is larger,the proportion of dead zone is smaller,and the whole molten pool is fully stirred.When the insertion depth of the side lance is deeper,the gas holdup in the molten pool is greater and the stirring of the molten pool is more intense,while the insertion angle has little effect on the gas holdup.By comparing the influence of different side blowing conditions on the slag layer,it is found that the slag layer is divided into two layers by double-layer side lance,with the critical surface of the slag layer at about 200-260 mm from the bottom,and the insertion depth of the lower side lance has a greater influence on the layering of the slag.

关键词： Iron bath smelting reduction Side-bottom combined blowing Numerical simulation Mixing time Slag layering

Composition design of high yield strength points in single-phase Co-Cr-Fe-Ni-Mo multi-principal element alloys system based on electronegativity,thermodynamic calculations,and machine learning

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Tungsten 2023年第1期5卷 169-178页

作者： Jiao-Hui Yan Zi-Jing Song Wei Fang xin-Bo He Ruo-Bin Chang Shao-Wu Huang Jia-xin Huang Hao-Yang Yu Fu-xing Yin Research Institute for Energy Equipment Materials School of Materials Science and EngineeringHebei University of TechnologyTianjin 300132China Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology Tianjin 300132China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

A method which combines electronegativity difference,CALculation of PHAse Diagrams(CALPHAD) and machine learning has been proposed to efficiently screen the high yield strength regions in Co-Cr-Fe-Ni-Mo multi-component phase diagram.First,the single-phase region at a certain annealing temperature is obtained by combining CALPHAD method and machine learning,to avoid the formation of brittle phases.Then high yield strength points in the single-phase region are selected by electronegativity difference.The yield strength and plastic deformation behavior of the designed Co_(14)Cr_(30)Ni_(50)Mo_(6)alloy are measured to evaluate the proposed method.The validation experiments indicate this method is effective to predict high yield strength points in the whole compositional space.Meanwhile,the interactions between the high density of shear bands and dislocations contribute to the high ductility and good work hardening ability of Co_(14)Cr_(30)Ni_(50)Mo_(6)alloy.The method is helpful and instructive to property-oriented compositional design for multi-principal element alloys.

关键词： High entropy alloys Multi-principal element alloys Yield strength Electronegativity difference CALculation of PHAse Diagrams Machine learning

Thermal properties of diamond/Al composites by pressure infiltration:comparison between methods of coating Ti onto diamond surfaces and adding Si into Al matrix

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Rare Metals 2016年第3期35卷 249-255页

作者： Cai-Yu Guo xin-Bo He Shu-Bin Ren Xuan-Hui Qu Institute for Advanced Materials and Technology University of Science and Technology Beijing

This study was pertained to the effects of Ti coating on diamond surfaces and Si addition into Al matrix on the thermal conductivity（TC） and the coefficient of thermal expansion（CTE） of diamond/Al composites by pressure infiltration.The fracture surfaces,interface microstructures by metal electro-etching and interfacial thermal conductance of the composites prepared by two methods were compared.The results reveal that Ti coating on diamond surfaces and only12.2 wt% Si addition into Al matrix could both improve the interfacial bonding and increase the TCs of the composites.But the Ti coating layer introduces more interfacial thermal barrier at the diamond/Al interface compared to adding 12.2 wt% Si into Al matrix.The diamond/Al composite with 12.2 wt% Si addition exhibits maximum TC of 534 W·m^-1·K^-1and a very low CTE of 8.9×10^-6K^-1,while the coating Ti-diamond/Al composite has a TC of 514 W·m^-1·K^-1 and a CTE of 11.0×10^-6K^-1.

关键词： Metal matrix composites Coating Thermal conductivity Coefficient of thermal expansion Pressure infiltration