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Influence of Annealing Treatments on Microstructure and Mechanical Properties of an Extruded Mg AZ31/Al 7050 Laminate

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 227-234页

作者： Yang Wu yun-chang xin Xiang-Sheng Xia Bo Feng Yan-Bin Wang Zu-De Zhao Southwest Technology and Engineering Research Institute International Joint Laboratory for Light Alloys College of Materials Science and Engineering Chongqing University Guangdong Institute of Materials and Processing Guangdong Academy of Sciences

Mg AZ31/A1 7050 laminate was fabricated by co-extrusion directly from the as-cast Mg AZ31 and Al 7050 billets. The influence of annealing temperature and annealing time on microstructure and mechanical behavior of the extruded Mg/Al laminate was systematically studied. Results show that annealing treatments at 250 ℃ for 3 h or at 350 ℃ for 3 h do not result in an obvious grain coarsening of Mg layer and cannot remove the heterogeneous structure. Annealing does not vary texture in the Mg layer, a large fraction of //ND and a small fraction of //TD, but the intensity of component //ND weakens to some extent. Lamellar microstructure in the A1 layer remains after annealing at250 ℃ for 3 h or at 350 ℃ for 3 h. High fractions of the texture components S and cube exist in the extruded sample, and annealing treatment hardly changes their fractions. Post-annealing treatment will largely reduce yield strength of extruded plate and increase plasticity slightly. The yield strength drops from 302 MPa to 206 MPa after annealing at 250 ℃ for 3 h and to 141 MPa after annealing at 350 ℃ for 3 h. The elongation to fracture increases from 1.5% to 5.4% after annealing at 250 ℃ for 3 h and to 4.8% at 350 ℃ for 3 h. The corresponding mechanism was discussed.

关键词： Laminate composite Annealing Microstructure Texture Mechanical property

Mechanical and Corrosion Behavior of a Biomedical Mg–6Zn–0.5Zr Alloy Containing a Large Number of Twins

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Acta Metallurgica Sinica(English Letters) 2023年第3期36卷 439-455页

作者： chang‑Jian Yan Bo Guan yun‑chang xin Ling‑Yu Zhao Guang‑Jie Huang Rui Hong Xiao‑Bo Chen Paul K.Chu Institute of Corrosion Science and Technology Guangdong 510070China International Joint Laboratory for Light Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400030China Key Laboratory for Light‑Weight Materials Nanjing Tech UniversityNanjing 210009China School of Mechanical Engineering Yangzhou UniversityYangzhou 225127China School of Engineering RMIT UniversityCarlton 3053VICAustralia Department of Physics Department of Materials Science&EngineeringDepartment of Biomedical EngineeringCity University of Hong KongTat Chee AvenueKowloonHong KongChina Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

The strong texture of Mg alloys can lead to strong tension–compression yield asymmetry and corrosion anisotropy,and this will consequently affect the effectiveness of hard tissue implants.A biomedical Mg–6Zn–0.5Zr alloy containing a large number of{1012}primary twins and{1012}–{1012}secondary twins is successfully prepared by cross *** dual twin structure not only removes the tension–compression yield asymmetry completely,but effectively reduces the corrosion anisotropy without compromise of corrosion *** difference between the largest corrosion rate and smallest one is~1.2 times compared to~1.6 times of the original *** is found that the reduced corrosion anisotropy is related to re-distribution of crystallographic orientations by twins.

关键词： Biomedical Mg alloy Corrosion Mechanical anisotropy Texture Twins

Hot Deformation Behavior and Hardness of a CoCrFeMnNi High-Entropy Alloy with High Content of Carbon

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Acta Metallurgica Sinica(English Letters) 2019年第8期32卷 932-943页

作者： Yi-Tao Wang Jian-Bo Li yun-chang xin Xian-Hua Chen Muhammad Rashad Bin Liu Yong Liu School of Materials Science and Engineering Chongqing UniversityChongqing 400044China International Joint Laboratory for Light Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400030China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

A CoCrFeMnNi high-entropy alloy with a high content of carbon was synthesized,and its hot deformation behavior was studied at the temperatures 800-1000℃at the strain rates ranging from 0.001 to 0.1s^-***-prepared alloy is a face-centered cubic-structured solid solution,with a large amount of carbides residing at grain *** stress-strain curves were employed to develop the constitutive equation of apparent activation *** apparent activation energy(Q)was found to be 423 kJ mol^-1,indicating a dynamic flow softening behaviThe size of dynamic recrystallized(DRXed)grains increases with increasing the temperature or decreasing the strain rate.A processing map was sketched on the basis of the flow *** temperature range of 900-1000℃and 10^-3-10^-2 6 s^-1 strain rate were found to be the optimum hot-forging *** increasing temperature or decreasing strain rate,the volume fraction of fine carbides(≤1μm)increases.A lot of coarse carbides can be found in the matrix after deformation at 800℃,which leads to a high hardness value of 345 *** carbides after deformation at 1000℃are mainly nano-sized M7C3 and M23C6,which can promote the nucleation of DRX.

关键词： High-entropy alloy Carbon Apparent activation energy Processing map Dynamic recrystallization

Insight from in situ microscopy into which precipitate morphology can enable high strength in magnesium alloys

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Journal of Materials Science & Technology 2018年第7期34卷 1061-1066页

作者： Bo-Yu Liu Nan Yang Jian Wang Matthew Barnett yun-chang xin Di Wu Ren-Long xin Bin Li R. Lakshmi Narayan Jian-Feng Nie Ju Li Evan Ma Zhi-Wei Shan Center for Advancing Materials Performance from the Nanoscale (CAMP-Nano) & Hysitron Applied Research Center in China (HARCC) State Key Laboratory for Mechanical Behavior of Materials Xi' an Jiaotong University Xi' an 710049. People's Republic of China Mechanical and Materials Engineering University of Nebraska-Lincoln Lincoln NE 68588 USA Institute for Frontier Materials Deakin University Geelong Victoria 3216 Australia College of Materials Science and Engineering Chongqing University Chongqing 400045 People's Republic of China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 People's Republic of China Department of Chemical and Materials Engineering University of Nevada Reno USA Department of Materials Science and Engineering Carnegie Mellon University Pittsburgh PA 15213 USA Department of Materials Science and Engineering Monash University Melbourne Victoria 3800 Australia Department of Nuclear Science and Engineering and Department of Materials Science and Engineering Massachusetts Institute of Technology 77 Massachusetts Avenue Cambridge MA 02139 USA Department of Materials Science and Engineering Johns Hopkins University Baltimore MD 21218 USA

Magnesium alloys, while boasting light weight, suffer from a major drawback in their relatively low strength. Identifying the microstructural features that are most effective in strengthening is therefore a pressing challenge. Deformation twinning often mediates plastic yielding in magnesium alloys. Unfortunately, due to the complexity involved in the twinning mechanism and twin-precipitate interactions, the optimal precipitate morphology that can best impede twinning has yet to be singled out. Based on the understanding of twinning mechanism in magnesium alloys, here we propose that the lamellar precipitates or the network of plate-shaped precipitates are most effective in suppressing deformation twinning. This has been verified through quantitative in situ tests inside a transmission electron microscope on a series of magnesium alloys containing precipitates with different morphology. The insight gained is expected to have general implications for strengthening strategies and alloy design. 2018 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Precipitate selection criterionIn-situ TEM Mg alloy Mechanical property Deformation twinning

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掺氢功率比对富氢甲烷燃烧振荡特性的影响

推进技术 2023年第1期44卷 182-195页

作者：昌运鑫宋恒韩猛刘玉治韩啸林宇震北京航空航天大学航空发动机研究院航空发动机气动热力国家级重点实验室北京100191 北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191

为探究工程应用中富氢甲烷对燃烧振荡的影响,在北航BASIS燃烧器上针对富氢甲烷的中心分层火焰展开实验研究。分析主燃级当量比、预燃级当量比、主燃级掺氢功率比(氢气功率与主燃级燃料功率的比值)对燃烧振荡的影响。保持预燃级空气流量... 详细信息

为探究工程应用中富氢甲烷对燃烧振荡的影响,在北航BASIS燃烧器上针对富氢甲烷的中心分层火焰展开实验研究。分析主燃级当量比、预燃级当量比、主燃级掺氢功率比(氢气功率与主燃级燃料功率的比值)对燃烧振荡的影响。保持预燃级空气流量为2g/s,主燃级空气流量为10g/s,围绕主燃级当量比、预燃级当量比、主燃级掺氢功率比进行24个工况下的128组试验。试验对火焰压力脉动的振幅与频率进行测量,并结合火焰宏观形状进行分析研究,发现对于大多数当量比的工况,富氢甲烷火焰都处于同一模态,出现火焰分层现象但不产生燃烧振荡。主燃级当量比ϕ_(main)=0.6与0.55时,富氢甲烷火焰脉动振幅随掺氢比加大,先增后减,分别有42%和32%的工况发生燃烧振荡。ϕ_(main)=0.5时,燃烧振荡只在高预燃级当量比(ϕ_(pilot))、高掺氢比时发生,仅有7%的工况出现燃烧振荡。因此,为实现更大的减碳比例,在不改变燃烧器构型的情况下,大掺氢功率比燃烧需要工作在主燃级和预燃级非常贫油的条件下。在部分工况中,掺加氢气可以在一定程度上减弱热声振荡的强度。

关键词：富氢甲烷燃烧振荡分层旋流火焰贫油燃烧掺氢功率比

Deformation twinning and textural evolution of pure zirconium during rolling at low temperature

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Transactions of Nonferrous Metals Society of China 2013年第10期23卷 2890-2895页

作者：栾佰峰叶青陈建伟余泓冰邹东利信运昌重庆大学材料科学与工程学院重庆400044

Industry pure zirconium sheets with a strong c-axis fiber texture were rolled to different strains at 77 K to investigate the twinning behavior and deformation mechanism. The microstructure and texture of the rolled specimens were characterized by scanning electron microscopy （SEM） together with electron backscatter diffraction （EBSD） techniques. The results show that the {1022} （1123） compression twinning mode is the dominant deformation twin at low strains loaded along the c-axis, and the {1012} （ 10]- 1 ） tensile twinning generates as the second twin in {1022} （ 1123 ） twins. The selection of twinning modes is governed by Schmid factor （SF） due to the calculating of SF and the EBSD simulating of twinning distribution. The evolution of texture during rolling affected by twins with increase of the strain was explained.

关键词： zirconium twinning texture rolling

Comparative proteomic analysis of plasma exosomes reveals the functional contribution of N-acetyl-alpha-glucosaminidase to Parkinson’s disease

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Neural Regeneration Research 2025年第10期20卷 2998-3012页

作者： Yuan Zhao Yidan Zhang xin Liu Jian Zhang Ya Gao Shuyue Li Cui chang Xiang Liu Guofeng Yang Department of Geriatrics Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Neurosurgery The Second Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina

Parkinson’s disease is the second most common progressive neurodegenerative disorder,and few reliable biomarkers are available to track disease *** proteins,DNA,mRNA,and lipids carried by exosomes reflect intracellular changes,and thus can serve as biomarkers for a variety of *** this study,we investigated alterations in the protein content of plasma exosomes derived from patients with Parkinson’s disease and the potential therapeutic roles of these proteins in Parkinson’s *** a tandem mass tag-based quantitative proteomics approach,we characterized the proteomes of plasma exosomes derived from individual patients,identified exosomal protein signatures specific to patients with Parkinson’s disease,and identified N-acetyl-alpha-glucosaminidase as a differentially expressed protein.N-acetyl-alpha-glucosaminidase expression levels in exosomes from the plasma of patients and healthy controls were validated by enzyme-linked immunosorbent assay and western *** results demonstrated that the exosomal N-acetyl-alpha-glucosaminidase concentration was not only lower in Parkinson’s disease,but also decreased with increasing Hoehn-Yahr stage,suggesting that N-acetyl-alpha-glucosaminidase could be used to rapidly evaluate Parkinson’s disease ***,western blot and immunohistochemistry analysis showed that N-acetyl-alpha-glucosaminidase levels were markedly reduced both in cells treated with 1-methyl-4-phenylpyridinium and cells overexpressingα-synuclein compared with control ***,N-acetyl-alpha-glucosaminidase overexpression significantly increased cell viability and inhibitedα-synuclein expression in 1-methyl-4-phenylpyridinium-treated *** together,our findings demonstrate for the first time that exosomal N-acetyl-alpha-glucosaminidase may serve as a biomarker for Parkinson’s disease diagnosis,and that N-acetyl-alpha-glucosaminidase may reduceα-synuclein expression and 1-methyl-4-phenylpyridinium-induced n

关键词： biomarker diagnosis exosomes N-acetyl-alpha-glucosaminidase Parkinson’s disease proteomic α-synuclein

Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator

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Nano-Micro Letters 2025年第1期17卷 378-403页

作者： Bin Xie Yuanhui Guo yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma xin Chen Chingping Wong State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006People’s Republic of China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation *** nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this *** the core component of TENG,the choice of electrode materials significantly affects its *** metal electrode materials often suffer from problems such as durability,which limits the further application of ***,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical *** review systematically summarizes the recent research progress and application prospects of TENGs based on graphene *** precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are *** addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs.

关键词： Triboelectric nanogenerator Precision processing Graphene electrode Self-powered sensor

Metal-organic frameworks with dinuclear metal centers for synergistically boosting CO2 photoreduction

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Science China Chemistry 2025年第01期 201-208页

作者： Hui-Feng Wang Wen-Jie Shi Yu-xin Yang Bao-Xia Dong Tong-Bu Lu Di-chang Zhong School of Chemistry and Chemical Engineering Yangzhou University Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and Engineering Tianjin University of Technology

Dinuclear metal synergistic catalysis （DMSC） has been proved powerful in boosting CO2reduction,while this has not been achieved in heterogeneous catalysts with long-range order *** this study,we,by introduction of metal catalytic centers into an indium-based metal-organic framework （MOF）,obtained a series of isostructural In-MOFs,including three MOFs with mononuclear metal catalytic center （M-In）,three MOFs with dinuclear homometallic catalytic centers （MM-In）,and three MOFs with dinuclear heterometallic catalytic centers (MM’-In,M/M’=Co（II）,Ni（II）,Zn（II）).It was found that all these MOFs can serve as catalysts for photochemical CO2reduction to *** with M-In,the catalytic activities of MM-In were obviously enhanced,and that of MM’-In was further significantly *** example,the CO yield of Co Zn-In reaches a record value of 12,700μmol g-1h-1,which is 4.0,8.1,9.4,and 18.6-fold higher than that of Co Co-In,Zn Zn-In,Co-In,and Zn-In,***,the catalytic activities of Co Ni-In and Ni Zn-In also show different fold increase than those of corresponding dinuclear homometallic and mononuclear metallic *** results of control experiments and theoretical calculation reveal that the higher catalytic activities of MM-In over M-In can be ascribed to the DMSC effect,and the higher catalytic activity of MM’-In over MM-In can be ascribed to the strengthened DMSC *** work reveals the relationship between DMSC effect and bimetal centers in CO2reduction,which provides new insights into the DMSC and paves a new way to design highly active catalysts for photochemical CO2reduction.

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