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Effect of Initial Microstructure Prior to Extrusion on the Microstructure and Mechanical Properties of Extruded AZ80 Alloy with a Low Temperature and a Low Ratio

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 339-349页

作者： Hang Zhang Haipeng li rongguang li Boshu liu Ruizhi Wu Dongyue Zhao Shanshan li School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang 110142China Key Laboratory of Superlight Materials&Surface Technology Ministry of EducationHarbin Engineering UniversityHarbin 150001China

Magnesium(Mg)alloys are the lightest metal structural material for engineering applications and therefore have a wide market of ***,compared to steel and aluminum alloys,Mg alloys have lower mechanical properties,which greatly limits their *** is one of the most important processing methods for Mg and its ***,the effect of such a heterogeneous microstructure achieved at low temperatures on the mechanical properties is lacking *** this work,commercial AZ80 alloys with different initial microstructures(as-cast and as-homogenized)were selected and extruded at a low extrusion temperature of 220℃and a low extrusion ratio of *** microstructure and mechanical properties of the two extruded AZ80 alloys were *** results show that homogenized-extruded(HE)sample exhibits higher strength than the cast-extruded(CE)sample,which is mainly attributed to the high number density of fine dynamic precipitates and the high fraction of recrystallized ultrafine *** to the coarse compounds existing in CE sample,the fine dynamical precipitates of Mg17(Al,Zn)12form in the HE sample can effectively promote the dynamical recrystallization during extrusion,while they exhibit a similar effect on the size and orientation of the recrystallized *** results can facilitate the designing of high-strength wrought magnesium alloys by rational microstructure construction.

关键词： Magnesium alloy Low temperature and low ratio extrusion Bimodal grain structure Dynamic precipitate Dynamic recrystallization

Development of extruded Mg-6Er-3Y-1.5Zn-0.4Mn(wt.%) alloy with high strength at elevated temperature

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Journal of Materials Science & Technology 2019年第10期35卷 2365-2374页

作者： Mingquan Zhang Yan Feng Jinghuai Zhang Shujuan liu Qiang Yang Zhuang liu rongguang li Jian Meng Ruizhi Wu Key Laboratory of Superlight Material and Surface Technology Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Department of Materials Physics and Chemistry Harbin Institute of TechnologyHarbin 150001China State Key Laboratory of Rare Earth Resources Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China School of Mechanical Engineering Shenyang University of Chemical TechnologyShenyang 110142China

A new Mg-6 Er-3 Y-1.5 Zn-0.4 Mn(wt.%) alloy with high strength at high temperature was designed and extruded at 350℃. The as-extruded alloy exhibits ultimate tensile strength of 301 MPa, yield strength(along ED) of 274 MPa and thermal conductivity of 73 W/m·K at 300℃. Such outstanding hightemperature strength is mainly attributed to the formation of nano-spaced solute-segregated basal plane stacking faults(SFs) with a large aspect ratio throughout the entire Mg matrix, fine dynamically recrystallized(DRXed) grains of 1–2μm and strongly textured un-DRXed grains with numerous *** examination unveils that long period stacking ordered(LPSO) phases are formed in Mg matrix of the as-cast alloy when rational design of alloy composition was employed, i.e.(Er + Y): Zn = 3:1 and Er: Y = 1: 1(at.%). It is worth mentioning that it is the first report regarding the formation of nano-spaced basal plane SFs throughout both DRXed and un-DRXed grains in as-extruded alloy with well-designed compositions and processing parameters. The results provide new opportunities to the development of deformed Mg alloys with satisfactory mechanical performance for high-temperature services.

关键词： Mg alloys Stacking faults Mechanical properties Thermal conductivity

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血清胸腺因子的大鼠围产期毒性试验研究

癌变．畸变．突变 2024年第2期36卷 138-142页

作者：杨玉李荣光王丹黄雅理单纯刘师卜林飞佳木斯大学基础医学院黑龙江佳木斯154007 中国食品药品检定研究院北京100050 佳木斯大学附属第二医院黑龙江佳木斯154007 佳木斯大学临床医学院黑龙江佳木斯154007 海关总署国际检验检疫标准与技术法规研究中心北京100013

目的:观察血清胸腺因子对大鼠妊娠晚期、分娩期、哺乳期及胚胎和胎仔出生后生长发育、学习能力以及生殖能力的影响。方法:选择交配后的雌性SD大鼠,每组20只,从妊娠第15天至哺乳期结束,分别按0.88、1.75和3.50 mg/kg连续皮下注射给予血... 详细信息

目的:观察血清胸腺因子对大鼠妊娠晚期、分娩期、哺乳期及胚胎和胎仔出生后生长发育、学习能力以及生殖能力的影响。方法:选择交配后的雌性SD大鼠,每组20只,从妊娠第15天至哺乳期结束,分别按0.88、1.75和3.50 mg/kg连续皮下注射给予血清胸腺因子,同时设0.9%氯化钠注射液为溶剂对照组,定期称取F0代雌鼠体质量、摄食量;F1代仔鼠确定出生存活率、哺乳期存活率,生理发育、新生反射达标天龄,训练学习、记忆能力,观察出生第12周后的仔鼠交配后的生殖行为,测定胚胎毒性各项指标。结果:注射血清胸腺因子后,溶剂对照组和受试药物各剂量组F0代妊娠鼠和哺乳鼠各周的平均体质量增长和摄食量正常,仔鼠总量、性别比和出生存活率(96.3%~97.9%)和哺乳期存活率(97.7%~98.9%)基本一致;F1代仔鼠的哺乳期和离乳后仔鼠平均体质量增长和摄食量基本正常。溶剂对照组仔鼠的生理发育和新生反射时间点检查项目均为正常达标天龄,游泳适应时间(28.5±15.8)s,空间定位建立时间(134.9±44.1)s,暗室电击反射建立时间(4.9±3.1)s,建立记忆电击次数1.7±0.9;F1代性成熟大鼠溶剂对照组的同笼交配率100%,妊娠率90%,平均着床数10.6±2.1,平均活胎数10.2±1.9,死胎数3,畸形胎数1;以上指标受试药物各剂量组间未见明显变化,与溶剂对照组比较,差异均无统计学意义(P>0.05)。结论:在本实验条件下,溶剂对照组与血清胸腺因子3个剂量组的大鼠妊娠后期个体及F1代胚胎及胎仔出生后生长发育、神经行为以及生殖能力等均未发现明显异常,未见围产期毒性反应。

关键词：血清胸腺因子大鼠仔鼠生长发育生殖毒性

Cathodic corrosion as a facile and universal method for scalable preparation of powdery single atom electrocatalysts

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Nano Research 2024年第6期17卷 4943-4950页

作者： Rui li Xiayan Yan Meng liu Qingkai Zhao Jie Du Xinxin Tan Jingwen Ba rongguang Zeng Wenhua Luo Jingsong Xu Institute of Materials China Academy of Engineering PhysicsJiangyou 621907China Science and Technology on Surface Physics and Chemistry Laboratory Jiangyou 621908China

Top-down strategy has been widely applied for synthesis of metal single atom catalysts(SACs)via converting metal nanoparticles or bulk metals into atomically dispersed ***,we report a simple electrochemical atomic migration strategy for top-down synthesis of SACs via a facile cathodic corrosion process without involving high temperature or harsh *** of metal nanoparticles on cathode are firstly disbanded under high negative voltage,and emitted into the electrolyte in the form of atomic metal anions in Zintl *** escaped atomically dispersed metal species are then oxidized by water molecules and captured by the defects on the pre-added nitrogen doped carbon carriers in the *** cathodic corrosion strategy is confirmed to be suitable for scalable synthesis of kinds of metal SACs(e.g.,Pt,Pd,and Ir)on doped carbon ***,the as-prepared nitrogen doped carbon powder supported Pt SACs exhibit superior catalytic activity toward hydrogen evolution reaction(HER)with a low overpotential of 0.024 V at 10 mA·cm^(−2)and a low Tafel slope of 29.7 mV·dec^(−1)as well as a long-term durability.

关键词： cathodic corrosion top-down strategy powdery single atom catalysts hydrogen evolution reaction scalable synthesis

Dry sliding wear behavior of extruded Mg-Sn-Yb alloy

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Journal of Rare Earths 2015年第1期33卷 77-85页

作者：姜静毕广利赵磊李荣广连建设江中浩 Key Laboratory of Automobile Materials College of Materials Science and Engineering Jilin University State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Mechanical Engineering Shenyang University of Chemical Technology

The dry sliding wear behavior of extruded Mg-9Sn and Mg-9Sn-3Yb alloys through pin-on-disc configuration was investigated at room temperature. Coefficient of friction, wear rate and wear resistance of extruded Mg-9Sn and Mg-9Sn-3Yb alloys were measured within a load range of 20-240 N and 20-380 N at a sliding velocity of 0.785 m/s, respectively. The wear tracks, worn surface and wear edge were observed using a scanning electron microscope and an energy dispersive X-ray spectrometer. The results indicated that wear rate, coefficient of friction and wear resistance changed with increasing applied load due to different wear mechanisms. Six wear mechanisms, namely adhesion, abrasion, oxidation, delamination, thermal softening and melting, were observed for both extruded alloys. The extruded Mg-9Sn-3Yb alloy exhibited good wear resistance compared with extruded Mg-9Sn alloy, which was mainly attributed to a large number of volume fraction of Mg2 Sn particles, the formation of thermal stable Mg2（Sn,Yb） particles and good elevated temperature mechanical properties.

关键词： Mg-Sn-Yb alloy coefficient of friction wear resistance wear mechanism rare earths

激光熔覆Fe-Ti-V-C合金微观组织与磨损性能

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机械工程学报 2017年第2期53卷 67-73页

作者：宗琳李荣广张小玲沈阳化工大学机械工程学院沈阳110142

采用激光熔覆技术在20G基体上制备五组不同Ti质量分数的Fe-Ti-V-C系合金,利用金相显微镜、扫描电子显微镜、X射线衍射仪、显微硬度计和磨料磨损试验机等仪器对各熔覆层的显微组织、硬度和耐磨性进行测试和分析。试验结果表明:五组合金... 详细信息

采用激光熔覆技术在20G基体上制备五组不同Ti质量分数的Fe-Ti-V-C系合金,利用金相显微镜、扫描电子显微镜、X射线衍射仪、显微硬度计和磨料磨损试验机等仪器对各熔覆层的显微组织、硬度和耐磨性进行测试和分析。试验结果表明:五组合金熔覆层基体组织均由铁素体和马氏体构成;随着熔覆层中Ti质量分数的增加,针状马氏体基体组织转变为板条马氏体;初生(Ti,V)C的形态由树枝状和花瓣状向颗粒状转变,同时碳化物(Ti,V)C的数量逐渐增多,当Ti质量分数为14.7%时,碳化物的数量达到最高值。熔覆层截面显微硬度梯度分布合理,表层硬度达到700~950 HV0.2。湿砂磨粒磨损试验表明:适量Ti显著提高了熔覆层的耐磨性,熔覆层中随着Ti质量分数的提高,耐磨性先降低后提高,当Ti质量分数为14.7%时,大量颗粒状(Ti,V)C均匀弥散分布在铁素体及板条马氏体基体上,使得熔覆层具有最佳的耐磨性。

关键词：激光熔覆耐磨性显微组织 Fe-Ti-V-C合金

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论非物质文化遗产权的国家给付义务

文化遗产 2023年第2期 27-34页

作者：李荣光中南大学法学院湖南长沙410006

非物质文化遗产权是公民基本权利中文化权的具体表现形式,故其具备基本权利属性。公民基本权利的行使需要国家履行相应义务。尊重义务、保护义务、给付义务是国家义务结构理论的主要内容,其中给付义务是公民基本权利保障的核心。给付义... 详细信息

非物质文化遗产权是公民基本权利中文化权的具体表现形式,故其具备基本权利属性。公民基本权利的行使需要国家履行相应义务。尊重义务、保护义务、给付义务是国家义务结构理论的主要内容,其中给付义务是公民基本权利保障的核心。给付义务包括物质性给付、服务性给付和制度性给付三个方面。为确保国家给付义务的充分履行,维护权利主体的非物质文化遗产权利,应通过完善公众监督、优化规范审查以及健全公益诉讼的方式构建权利救济机制。

关键词：非遗基本权利国家给付权利救济

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管道缺陷碳纤维修复技术树脂体系的改进试验

油气储运 2009年第8期28卷 48-51页

作者：李荣光中国石油管道研究中心

针对修复管道缺陷使用的碳纤维材料存在老化、附着力下降等问题,提出了增强复合材料树脂体系附着力、提高耐冲击性能和加强固化度等的具体措施。通过改进试验,在树脂配方中添加偶联剂(KH-550)、增韧剂(KZ-686)等功能性助剂,提高了树脂... 详细信息

针对修复管道缺陷使用的碳纤维材料存在老化、附着力下降等问题,提出了增强复合材料树脂体系附着力、提高耐冲击性能和加强固化度等的具体措施。通过改进试验,在树脂配方中添加偶联剂(KH-550)、增韧剂(KZ-686)等功能性助剂,提高了树脂体系的综合防腐性能。

关键词：管道碳纤维复合材料缺陷修复环氧树脂性能改进试验

E2500验证标准在药厂项目中的探讨与应用

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中国医药工业杂志 2017年第8期48卷 1225-1230页

作者：李荣光杨世民西安交通大学药学院陕西西安710061 西安杨森制药有限公司陕西西安710043

本文目的在于通过对E2500验证标准的介绍并结合E2500在药厂项目中的应用,就如何制定基于项目的 E2500实施流程重点展开讨论,以科学理论为基础,通过关键方面风险评估(CARA)及关键方面设计评审(CADR)、供应商及主题专家的深度参与等具体方... 详细信息

本文目的在于通过对E2500验证标准的介绍并结合E2500在药厂项目中的应用,就如何制定基于项目的 E2500实施流程重点展开讨论,以科学理论为基础,通过关键方面风险评估(CARA)及关键方面设计评审(CADR)、供应商及主题专家的深度参与等具体方法,实现符合工艺及质量要求的系统、设施和设备,达到既保证产品质量和患者安全,又能快速提高生产能力、降低确认活动成本的目的 ;并为同行或企业提供具有指导意义的参考依据。

关键词： E2500验证标准关键方面风险评估关键方面设计评审确证