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Journal of Materials Science & Technology 2013年第12期29卷 1116-1122页

作者： z.A.Luo G.M.Xie z.Y.Ma G.L.Wang G.d.Wang State Key Laboratory of Rolling and Automation Northeastern University Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

As-extruded zK60 and zK60-Y magnesium alloy plates were successfully processed via friction stir processing （FSP） at a tool rotation rate of 1600 r/rain and a traverse speed of 200 mm/min. FSP resulted in the formation of equiaxed recrystallized microstructures with the average grain sizes of ,-8.5 and -4.7 μm in the zK60 and zK60-Y alloys, respectively. Moreover, FSP broke and dispersed the Mgzn2 and W-phase （Mg3zn3Y2） particles and dissolved Mgzn2 phase in the FSP zK60 alloy. With the addition of rare earth element yttrium （Y） into the zK60 alloy, the ratio of the high angle grain boundaries （HAGBs） in the FSP alloys increased from 64% to 90%, and a certain amount of twins appeared in the FSP zK60-Y alloy. The maximum elongation of 1200% and optimum strain rate of 3 X 10-3 s-1 achieved at 450 °C in the FSP zK60-Y alloy were substantially higher than those of the FSP zK60 alloy. This is attributed to the fine grains with high ratio of HAGBs and the distribution of a large number of dispersed second phase particles with high thermal stability in the FSP zK60-Y alloy. Grain boundary sliding was identified as the primary deformation mechanism in the FSP zK60 and zK60-Y alloys from the superplastic data analyses and surficial morphology observations.

关键词： Magnesium alloy Friction stir processing Rare earth element Microstructure Superplasticity

Effect of post weld artificial aging and water cooling on microstructure and mechanical properties of friction stir welded 2198-T8 Al-Li joints

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Journal of Materials Science & Technology 2022年第28期123卷 92-112页

作者： Y.Tao z.zhang P.Xue d.R.Ni B.L.Xiao z.Y.Ma Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

Friction stir welding(FSW)under both air cooling and water cooling conditions with welding parameters of 800-1200 rpm rotation rates and 50-200 mm/min welding speeds was carried out on 2198-T8 Al-Li alloys,and post weld artificial aging was performed on the air cooled *** welding defects other than lazy S were observed in the nugget zone(Nz)for all *** air cooling condition,the lowest hardness zone(LHz)occurred in the heat affected zone(HAz).FSW resulted in gradual dissolution of original T_(1),θ′andδ′/β′from the base material(BM)to the thermo-mechanically affected zone(TMAz),and complete dissolution of all precipitates in the Nz withδ′/β′and Guinier-Preston zones precipitating during *** air cooled joints exhibited no noticeable changes in intrinsic tensile strength with a joint strength reaching 81.3%of the BM,but varied elongation with welding parameters,which was closely related to failure in the Nz and fracture along lazy *** weld artificial aging led to the largest hardness recovery in the TMAz but smaller hardness recovery in the initial LHz and the *** aging kinetics across the joint was determined by volume fraction of both original precipitate dissolu-tion during welding and coarse particles formed during aging,and by dislocation density inherited from *** weld artificial aging greatly enhanced the joint strength with the ultimate tensile strength reaching 87.3%of the *** compared to air cooling condition,water cooling hardly affected the Nz hardness and did not improve the joint strength,and the reason was discussed in light of precipitates,hardness changes and fracture behavior.

关键词： Friction stir welding Aluminum-lithium alloys Microstructure Mechanical properties

Influence of a liquid-filled compartment structure on the incoming shaped charge jet stability

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defence Technology（防务技术） 2021年第2期17卷 571-582页

作者： X.d.zu z.X.Huang z.W.Guan X.C.Yin Y.M.zheng School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing 210094China School of Engineering University of LiverpoolLiverpoolL693GQUK department of Mechanics and Engineering Science Nanjing University of Science and TechnologyNanjing 210094China

Liquid-filled compartment structure consists of a bulk steel plate with matrix blind holes which are filled with liquid and a steel front plate to seal up the liquid with rings and *** liquid-filled compartment structure can resist the shaped charge warhead *** paper presents experimental and theoretical investigations of the penetration ability of the residual shaped charge jet emerging from the liquid-filled compartment structure after the penetration process at different impact *** the basis of shock wave propagation theory,the influence of the liquid-filled compartment structure on jet stability is *** interferences of the liquid backflow caused by a reflected shock wave and a back plate on jet stability under different impact angles are also *** addition,the range of the disturbed velocity segments of the jet at different impact angles and the penetration ability of the residual jet are obtained.A theoretical model is validated against the experimental penetration depths.

关键词： Compartment structure Shaped charge jet Shock wave disturbance Stability

Anisotropic Electroplastic Effects on the Mechanical Properties of a Nano-Lamellar Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 534-542页

作者： Y.R.Ma H.J.Yang d.d.Ben X.H.Shao Y.z.Tian Q.Wang z.F.zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Sciences and Technology of ChinaHefei230026China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110016China

Effects of electropulsing treatment(EPT)on the microstructural evolution and mechanical properties of a cold-rolled 316 L austenitic stainless steel with nano-lamellar structure were *** EPT experiments were carried out with the electric current direction along the rolling direction(Rd)and the transverse direction(Td)of the samples,*** anisotropic electroplastic effects for the Rd and Td specimens,i.e.,reduced hardness/strength and enhanced ductility,were obtained owing to the different recrystallization behaviors of the Rd and Td specimens during *** Rd specimens after EPT with larger recrystallized grain size and higher volume fraction of recrystallization show lower strength and higher elongation than that of the Td *** main reason might be attributed to the change of the current direction in the two kinds of samples,which results in the different sensitivity of the microstructures to thermal and athermal effects during EPT.

关键词： Stainless steel Electroplastic effect Electropulsing Recrystallization Anisotropy Strength Plasticity

Magnetic and Electrical Behavior of MnTe_(1-x)Sb_x Alloys

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Journal of Materials Science & Technology 2011年第1期27卷 64-68页

作者： X.He Y.Q.zhang z.d.zhang Shenyang National Laboratory for Materials Science Institute of Metal Researchand International Center for Materials PhysicsChinese Academy of SciencesShenyang 110016China

The structure,specific heat,magnetic and electrical properties of MnTe1-xSbx（x=0,0.1,0.15,0.2 and 0.25） alloys have been *** MnTe1-xSbx alloys crystallize in a hexagonal NiAs-type structure,and the impurity of MnSb phase appears when x≥*** MnTe0.9Sb0.1 compound exhibits ferrimagnetic behavior with hysteresis loops even at 350 K,showing that the magnetic properties of MnTe compound are very sensitive to little compositional *** ferromagnetism in the MnTe1-xSbx alloys with higher Sb contents may be attributed to the impurity of MnSb *** dispersive X-ray spectroscopy analysis on the MnTe0.9Sb0.1 compound indicates that Sb is very difficult to dope into the lattice of *** the anomaly of resistivity at 300 K of MnTe0.9Sb0.1 and the peak of specific heat around 304 K of all the alloys are thought to be related with the antiferromagnetic interactions of MnTe-based lattice.

关键词： Electronic transport property Hysteresis loop Specific heat

MOdELING OF ISOTHERMAL PRECIPITATION KINETICS IN HSLA STEELS ANd ITS APPLICATION

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 902-906页

作者： X.M.zhao d.Wu L.z.zhang z.Y.Liu TheStateKeyLab.ofRollingandAutomation NortheastemUniversityShenyang110004China

Microalloying elements in high-strength low-alloy steels, such as Nb, Ti and V, precipitate during hot-rolling processes. On the basis of classical theory of nucleation and growth, quanti- tative modeling of isothermal precipitation was developed, which was tested by the stress rela- xation method, the calculated precipitation-time-temperature curve is in good agreements with the measured results, then the model was applied to predict the precipitation behavior during continuous cooling.

关键词： isothermal precipitation kinetics HSLA steel

determination of the total antioxidant and oxidant status of some galactagogue and herbal teas

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Food Science and Human Wellness 2020年第4期9卷 377-382页

作者： d.Agagunduz Gazi University Faculty of Health SciencesDepartment of Nutrition and DieteticsEmniyet MahallesiMuammer Yasar BostancıCaddesiBesevlerAnkara 06560Turkey

This research was aimed to evaluate the total antioxidant status(TAS)and the total oxidant status(TOS)of galactagogues and herbal *** and herbal teas used for other purposes were sold in the market for breastfeeding mothers and *** infusions were prepared by following brewing recipe on the ***(mmol/L)and TOS(mol/L)were measured and oxidative stress indices(OSI)were *** values of the mixed-herbal teas in granule form that sold as still tea were found to be higher((1.5±0.00)–(1.7±0.14)mmol/L)compared to other galactagogue tea types(Pd-herbal tea in classic tea bag was(1.0±0.06)mmol/L while the TAS value of the vitamin added mixed-herbal tea was(3.0±0.00)mmol/L(Pd TOS values of the night-teas were simultaneously found to be higher compared to herbal teas(Pdes,the highest OSI values among herbal teas was chamomile tea(6.96).In conclusion,antioxidant/oxidant status of galactagogues and other herbal teas might vary according to their form(powder or granule),type,variety of herbs in the composition,and the ***,some galactagogues and other herbal teas have high levels of oxidant activity as well as antioxidant ***,it seems that vitamin addition is important for balancing antioxidant/oxidant status of all tea types.

关键词： Galactagogue tea Herbal tea Antioxidant Oxidant

development and application of functional gene arrays for microbial community analysis

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中国有色金属学会会刊：英文版 2008年第6期18卷 1319-1327页

作者： z. L. HE J. d. VAN NOSTRANd L.Y. WU J. z. zHOU Institute for Environmental Genomics Department of Botany and Microbiology University of Oklahoma Norman OK 73019 USA

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计... 详细信息

功能的基因标记能关于功能的基因差异和微生物引起的社区的潜在的活动提供重要信息。尽管 microarray 技术成功地被使用了为纯文化学习基因表示，简单、人工的微生物引起的社区，改编如此的一种技术分析复杂微生物引起的社区仍然以设计，样品准备，和数据分析提出很多挑战。这个工作集中于功能的基因数组(FGA ) 的开发和应用程序为微生物引起的社区研究指向关键功能的基因标记。一些与 FGA 有关明确地给问题调音，例如 oligonucleotide 探查设计， nucleic 酸抽取和纯化，数据分析，特性，敏感，和量的能力详细被讨论。最近的研究证明了 FGA 能从许多自然环境关于微生物引起的社区提供特定、敏感、潜在地量的信息并且控制生态系统。这种技术被期望革命化微生物引起的社区的分析，并且连接微生物引起的结构到生态系统工作。

关键词：微数列应用函数基因标记微生物种群

Stability of plane-parallel flow of magnetic fluids under external magnetic fields

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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 295-310页

作者： P.z.S.PAz F.R.CUNHA Y.d.SOBRAL department of Mathematics University of BrasíliaCampus Universitário Darcy RibeiroBrasília-DF70910-900Brazil Laboratory of Microhydrodynamics and Rheology-Vortex Group Department of Mechanical EngineeringUniversity of BrasíliaCampus Universitário Darcy RibeiroBrasília-DF70910-900Brazil

In this work,we present a theoretical study on the stability of a two-dimensional plane Poiseuille flow of magnetic fluids in the presence of externally applied magnetic *** fluids are assumed to be incompressible,and their magnetization is coupled to the flow through a simple phenomenological *** parameters are defined,and the equations are perturbed around the base *** eigenvalues of the linearized system are computed using a finite difference scheme and studied with respect to the dimensionless parameters of the *** examine the cases of both the horizontal and vertical magnetic *** obtained results indicate that the flow is destabilized in the horizontally applied magnetic field,but stabilized in the vertically applied *** characterize the stability of the flow by computing the stability diagrams in terms of the dimensionless parameters and determine the variation in the critical Reynolds number in terms of the magnetic ***,we show that the superparamagnetic limit,in which the magnetization of the fluids decouples from hydrodynamics,recovers the same purely hydrodynamic critical Reynolds number,regardless of the applied field direction and of the values of the other dimensionless magnetic parameters.

关键词： hydrodynamic stability magnetic fluid Orr-Sommerfeld equation magnetization evolution

Microstructural Evolution and Mechanical Behavior of Friction-Stir-Welded dP1180 Advanced Ultrahigh Strength Steel

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 58-66页

作者： z.W.Wang G.M.Xie d.Wang H.zhang d.R.Ni P.Xue B.L.Xiao z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

Friction stir lap welding of a dP1180 advanced ultrahigh strength steel was successfully carried out by using three welding tools with different pin lengths. The effects of the welding heat input and material flow on the microstructure evolution of the joints were analyzed in detail. The relationship between pin length and mechanical properties of lap joints was studied. The results showed that the peak temperatures of all joints exceeded A c3, and martensite phases with similar morphologies were formed in the stir zones. These martensite retained good toughness due to the self-tempering effect. The formation of ferrite and tempered martensite was the main reason for the hardness reduction in heat-affected zone. The mechanical properties of the lap joints were determined by loading mode, features of lap interface and the joint defects. When the stir pin was inserted into the lower sheet with a depth of 0.4 mm, the lap joint exhibited the maximum tensile strength of 12.4 kN.

关键词： Advanced ultrahigh strength steel Friction stir welding Microstructure Mechanical behavior