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Chinese Physics C 2024年第7期48卷 181-190页

作者：谢萌冉沈留媛李健国李红蕙袁琪左维 Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Neutron-rich P,Cl,and K isotopes,particularly those with neutron numbers of approximately N=28,have attracted extensive experimental and theoretical *** utilize the ab initio valence-space in-medium similarity renormalization group approach,based on chiral nucleon-nucleon and three-nucleon forces,to investigate the exotic properties of these *** calculations of the low-lying spectra are performed.A key finding is the level inversion between 3/2^(+)_(1)and 1/2^(+)_(1)states in odd-A isotopes,attributed to the inversion ofπ0xod3/2 andπls1/2 single-particle *** ab initio calculations,which incorporate the three-nucleon forces,correlate closely with existing experimental *** calculations of effective proton single-particle energies provide deeper insights into the shell evolution for Z=14 and 16 *** results indicate that the three-body force plays important roles in the shell evolution for Z=14 and 16 sub-shells with neutron numbers ranging from 20 to ***,systematic ab initio calculations are conducted for the low-lying spectra of odd-odd *** results correspond with experimental data and provide new insights for future research into these isotopes up to and beyond the drip line.

关键词： ab initio calculations shell evolution low-lying spectra

Numerical simulation of precipitation kinetics in multicomponent alloys

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journal of Materials Science & Technology 2022年第33期128卷 98-106页

作者： K.Xu j.D.liu S.van der Zwaag W.Xu j.g.li School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Novel Aerospace Materials group Faculty of Aerospace EngineeringDelft University of TechnologyKluyverweg 12629 HSDelftThe Netherlands State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

A universal numerical model based on the particle size distribution(PSD)approach has been developed for the simulation of precipitation kinetics in multicomponent alloys during isothermal *** was implemented utilizing the classical nucleation theory(CNT).growth and coarsening were modeled by a single growth kinetics equation,which is constructed based on the interfacial diffusion flux balance and the capillarity *** partial off-diagonal terms in the diffusion matrix(diffusion of individual components in the matrix)were taken into account in the calculations to minimize the computational cost while coupling with CALPHAD to extract thermodynamics equilibrium around the interface.A new feature of the model is the incorporation of a more realistic spatial site distribution via a Voronoi construction in the characteristic cell,for the purpose of modifying the diffusion *** predictions of the precipitate dimensions and the precipitation kinetics were compared with the atom probe tomography(APT)measurements on ternary Ni-Al-Cr alloys isothermally aged at 873 *** is found that the temporal evolution of the dimensions and composition of the precipitates is well captured,as is the dependence on changes in the alloy *** new modification with Voronoi construction demonstrates that the overall precipitation kinetics depends on the density and the spatial site distribution of *** ability to handle sophisticated alloy chemistries by quantitative equations,the compositional sensitivity of microstructural characteristics emerging from the simulation results,and the ability to visualize the spatial distribution of precipitates make the work very promising for multicomponent alloy design and optimization.

关键词： Precipitation kinetics Thermodynamics Multicomponent PSD Voronoi construction

Stress-rupture behavior of a Re-containing Ni-base single crystal superalloy at high temperatures

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journal of Materials Science & Technology 2023年第32期163卷 237-244页

作者： g.L.Wang D.Q.Qi j.L.liu j.D.liu j.g.li Y.Z.Zhou X.F.Sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

A Re-containing Ni-base single crystal superalloy was used to investigate the elementary processes associated with stress-rupture behavior at different temperatures where theγʹrafting *** 900°C,the rupture behavior is mainly determined by the multiplication of dislocations within the wideningγchannels,which is closely linked with the propagation of microcracks along the inherentγ/γʹ*** rapid formation of lamellaγ/γʹraft structure,along with the developed-well interfacial dislocation networks,and its elastic instability are primarily responsible for the rupture behavior at 1100°*** is a clear curvature tendency in the Larson-Miller plot of stress-rupture lifetime in relation to stress at high *** indicates that the influence extent ofγʹrafting on stress-rupture behavior is sensitive to the acting conditions of temperature and stress.

关键词： Ni-based single crystal superalloy Re effect γʹrafting Stress-rupture behavior Elementary process Larson-Miller plot

Sample selection for models to represent ceramic cores fabricated by stereolithography three-dimensional printing

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journal of Materials Science & Technology 2022年第26期121卷 117-123页

作者： X.L.An j.j.liang j.g.li j.W.Chen Y.Z.Zhou X.F.Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Space Manufacturing Technology(CAS Key Lab) Beijing 100094China

Ceramic cores with good chemical stability and moderate mechanical properties near casting temperatures of 1550℃ for example are used for the manufacturing of internal structures of hollow blades,requiring complex structures and high precision[1–3].However,traditional preparation method based on investment casting is tedious,requiring not only long production cycles but also high cost[4].

关键词： investment printing ceramic

ground-state mass of ^(22)Al and test of state-of-the-art ab initio calculations

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Chinese Physics C 2024年第3期48卷 72-78页

作者：孙铭泽于越王新鹏王猛李健国张玉虎 K.Blaum 陈祖毅陈瑞九邓涵宇付超义葛文文黄文嘉焦红扬李红蕙李宏福罗胤芳廖挺 YuAlitvinov 司敏帅鹏史金阳王茜邢元明徐星徐瑚珊许甫荣袁琪 T.Yamaguchi 颜鑫亮杨建成原有进周小红周旭张敏曾奇 CAS Key Laboratory of High Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany gSI Helmholtzzentrum für Schwerionenforschung Planckstraße 164291 DarmstadtGermany Advanced Energy Science and Technology guangdong Laboratory Huizhou516007China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Department of Physics Saitama UniversitySaitama 338-8570Japan School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The ground-state mass excess of the T_(z)=−2 drip-line nucleus ^(22)Al is measured for the first time as 18103(10)keV using the newly-developed Bρ-defined isochronous mass spectrometry method at the cooler storage ring in *** new mass excess value allowed us to determine the excitation energies of the two low-lying 1+states in ^(22)Al with significantly reduced uncertainties of 51 *** compared to the analogue states in its mirror nucleus ^(22)F,the mirror energy differences of the two 1^(+)states in the ^(22)Al-^(22)F mirror pair are determined to be−625(51)keV and−330(51)*** excitation energies and mirror energy differences are used to test the state-of-the-art ab initio valence-space in-medium similarity renormalization group calculations with four sets of interactions derived from the chiral effective field *** mechanism leading to the large mirror energy differences is investigated and attributed to the occupation of theπs_(1/2) orbital.

关键词： nuclear mass Bρ-defined IMS mirror energy difference ab initio VS-IMSRg calculations chiral interactions

Misorientation dependent thermal condition-solute field cooperative effect on competitive grain growth in the converging case during directional solidification of a nickel-base superalloy

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journal of Materials Science & Technology 2022年第1期96卷 151-159页

作者： X.B.Meng j.g.li C.N.jing j.D.liu S.Y.Ma j.j.liang C.W.Zhang M.Wang B.T.Tang T.lin j.L.Chen X.L.Zhang Q.li School of Mechanical and Automotive Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering Shandong Jianzhu UniversityJinan 250014China AECC Shenyang liming Aero-Engine Co. LTD.Shenyang110043China College of Material Science and Engineering North Minzu UniversityYinchuan 750021China Faculty of electro-mechanical information Weifang University of Science and TechnologyShouguang262700China

Nowadays,thermal condition and solute field are considered as the potential dominant factors controlling competitive grain growth during directional solidification ***,the controlling modes and critical conditions of competitive grain growth have been drastically debated over the past two *** this work,thermal condition and solute field are combined to study the competitive grain growth in the converging case by experimental observation and numerical simulation of bicrystal *** find the competitive grain growth is controlled by the cooperative effect of thermal condition and solute field,and the controlling modes are related to the bicrystal misorientation between favorably and unfavorably oriented *** the unfavorably oriented grain is low misoriented,unfavorably oriented grain dominates grain selection,and the competitive grain growth performs as solute field ***,with the increase of unfavorably oriented grain’s misorientation,the grain selection converts into favorably oriented grain domination,and the competitive grain growth changes to thermal condition *** explain these abnormal transformation phenomena,we propose a misorientation dependent thermal condition-solute field cooperative domination model and identify the critical conditions by a critical misorientation(θ_(cm)).According to dynamic equation of dendrite growth,we calculate the critical misorientationθ;to prove this *** theoretical calculation results agree well with the experimental results.

关键词： Competitive grain growth Cooperative effect Thermal condition Solute field Critical misorientation Unusual overgrowth Abnormal transformation

STUDY ON gRANULATION MECHANISMS OF γ+(Fe,Mn)3C EUTECTICS IN AUSTENITE STEEL COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 449-456页

作者： g.F.liang Z.M.Xu Q.C.jiang j.g.li SchoolofMaterialsScienceandTechnology ShanghaiJiaotongUniversityShanghai200030China SchoolofMaterialsScience JilinUniversityChangchun130025China

Results presented in this paper contribute to investigation of the granulation mechanisms of γ+(Fe,Mn)3C eutectics in the austenite matrix composites (abbreviated EAMC). The specimens corresponding to the nominal composition of eutectic with controlled RE(Ce)-Mg agent modifier additions have been unidirectional solidified with a constant growth rate of 2.18μm/s at a fixed temperature gradient of 800K/cm using vertical Bridgeman method. With the RE-Mg agent modifier, the transition of solid/liquid (S/L) interface from columnar to dendrite (CDT), refinement and developed branching of γ and (Fe,Mn)3C phases in the eutectics, and the transition of growth style from faceted-nonfaceted (F/NF) to nonfaceted-nonfaceted (NF/NF) for γ and (Fe,Mn)3C phases in the eutectic have been observed and investigated theoretically. Those can explain the granulation of γ+(Fe,Mn)3C eutectics in the as cast because the roundness increases with the developed lateral branching of primary austenite dendrites, refinement of eutectics, and NF/NF growth of γ and (Fe,Mn)3C phases in the eutectic.

关键词： composite RE-Mg agent granulation unidirectional solidifica-tion

DEPENDENCE OF MICROSTRUCTURE SCALES OF EUTECTICS ON Ca-Si MODIFIER AMOUNT IN AUSTENITE STEEL COMPOSITES

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 651-654页

作者： g.F.liang Z.M.Xu Q.C.jiang j.g.li SchoolofMaterialsScienceandTechnology ShanghaiJiaotongUniversityShanghai200030China SchoolofEnvironmentalScienceandEngineeringjiaotongUniversity Shanghai200030China SchoolofMaterialsScience JilinUniversityChangchun130025China

Results presented in this paper contribute to investigation of the effect of the added Ca-Si modifier amount ( ) on the microstructure scales of granular γ-(Fe,Mn)3C eutectics such as the volume fraction (f) and diameter (d) in the austenite steel matrix composites (EAMC). Directional solidification of EAMC has been carried out using vertical Bridgman method at 50.6μms-1 with a constant temperature gradient about 800Kcm-1. The higher constitutional supercooling ahead of solid-liquid interface attributing to the larger results in the enlargement of γ-(Fe,Mn)3C coupled-zone and the increment of the nucleation rate of eutectics. Therefore, f increases with increasing . The branches of the primary austenite dendrites develop more greatly as increases, which limits the growth of eutectics. As a result, d decreases with increasing .

关键词： austenite steel eutectic microstructure directional solidification

Optimization of chemistry and process parameters for control of intermetallic formation in Mg sludges

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journal of Magnesium and Alloys 2024年第4期12卷 1431-1448页

作者： Y.Fu g.g.Wang A.Hu Y.li K.B.Thacker j.P.Weiler H.Hu Department of Mechanical Automotive and Materials EngineeringUniversity of Windsor401 Sunset AveWindsorOntario N9B 3P4Canada global Technology Centre Meridian Lightweight Technologies25 MacNab AveStrathroyOntario N7G 4H6Canada

Intermetallic formation in sludge during magnesium(Mg)melting,holding and high pressure die casting practices is a very important ***,very often it is overlooked by academia,original equipment manufacturers(OEM),metal ingot producers and even die *** aim of this study was to minimize the intermetallic formation in Mg sludge via the optimization of the chemistry and process *** Al8Mn5 intermetallic particles were identified by the microstructure analysis based on the Al and Mn *** design of experiment(DOE)technique,Taguchi method,was employed to minimize the intermetallic formation in the sludge of Mg alloys with various chemical compositions of Al,Mn,Fe,and different process parameters,holding temperature and holding *** sludge yield(SY)and intermetallic size(IS)was selected as two *** optimum combination of the levels in terms of minimizing the intermetallic formation were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,690℃ for the holding temperature and holding at 30 mins for the holding time,*** best combination for smallest intermetallic size were 9 wt.%Al,0.15 wt.%Mn,0.001 wt.%(10 ppm)Fe,630℃ for the holding temperature and holding at 60 mins for the holding time,*** groups of sludge factors,Chemical Sludge(CSF),Physical Sludge(PSF)and Comprehensive Sludge Factors(and CPSF)were established for prediction of sludge yields and intermetallic sizes in Al-containing Mg *** CPSF with five independent variables including both chemical elements and process parameters gave high accuracy in prediction,as the prediction of the PSF with only the two processing parameters of the melt holding temperature and time showed a relatively large deviation from the experimental *** Chemical Sludge Factor was primarily designed for small ingot producers and die casters with a limited melting and holding capacity,of which process parameters could be fixed *** Physical Sludge Factor could be used f

关键词： Magnesium sludge Al-Mn intermetallic Optimization Taguchi method Sludge factor Chemical composition Process parameter

Research status of plasma facing materials for the fusion reactors

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Research status of plasma facing materials for the fusion re...