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Rare Metals 2013年第4期32卷 338-346页

作者： Yan Xu lian-xi hu Yu Sun School of Materials Science and Engineering Harbin Institute of Technology School of Mechanical Engineering Beihua University

The deformation behavior and the microstruc-ture evolution of as-cast AZ91D magnesium alloy without pre-homogenization treatment were systematically inves-tigated. The flow stress behavior was studied by com-pression tests in strain rate range of 0.001-1.000 s^-1 and deformation temperature range of 220-380 ℃ with a maximum deformation strain of 60 %. The dependence of flow stress on deformation temperature and strain rate was described by hyperbolic sine constitutive equation. Through regression analysis, the average apparent activa- tion energy and coefficient of strain rate sensitivity were estimated to be 181.98 ***^-1 and 0.14, respectively. The results also reveal that the variation of peak stress depends on strain rate and deformation temperature. Microstructure observation shows that, at temperatures higher than 300 ℃ and strain rates lower than 0.01 s^-1, DRX developed extensively at the grain boundaries and in the core of coarse grains, resulting in a more homogeneous microstructure. Furthermore, the effects of strain, defor-mation temperature, strain rate, and eutectic β phase on the microstructure evolution of as-cast AZ91D magnesium alloy were discussed.

关键词： AZ91D magnesium alloy Isothermalcompression Constitutive equation Peak stress Microstructure evolution

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-Feng Zhou Yu Long Yan-liang Yi Cheng Deng lian-xi hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

Dynamic recrystallization kinetics of as-cast AZ91D alloy

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Transactions of Nonferrous Metals Society of China 2014年第6期24卷 1683-1689页

作者：徐岩胡连喜孙宇哈尔滨工业大学材料科学与工程学院哈尔滨150001 北华大学机械工程学院吉林132021

The flow behavior and dynamic recrystallization（DRX） behavior of an as-cast AZ91 D alloy were investigated systematically by applying the isothermal compression tests in temperature range of 220-380 ℃ and strain rate range of 0.001-1 s^-*** effect of temperature and strain rate on the DRX behavior was *** results indicate that the nucleation and growth of dynamic recrystallized grains easily occur at higher temperatures and lower strain *** evaluate the evolution of dynamic recrystallization,the DRX kinetics model was proposed based on the experimental data of true stress-true strain *** was revealed that the volume fraction of dynamic recrystallized grains increased with increasing strain in terms of S-curves.A good agreement between the proposed DRX kinetics model and microstructure observation results validates the accuracy of DRX kinetics model for AZ91 D alloy.

关键词： AZ91D magnesium alloy compression flow behavior dynamic recrystallization behavior kinetics model

Establishment of a novel constitutive model considering dynamic recrystallization behavior of Ti-22Al-25Nb alloy during hot deformation

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Transactions of Nonferrous Metals Society of China 2019年第3期29卷 546-557页

作者： Yu SUN Heng ZHANG Zhi-peng WAN Li-li REN lian-xi hu National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China China Nuclear Industry 23 Construction Co. Ltd. Beijing 101300 China

The hot deformation behavior of Ti-22Al-25Nb alloy fabricated by hot compressed sintering was investigated under various conditions of compression tests in the deformation temperature range of 975-1075 °C with 20 °C intervals and the strain rate range of 0.001-1.0 s^-1. Based on the experimental data, a novel constitutive relation combining a series of models was developed, including Zener-Hollomon parameter (Z), DRX critical model and kinetics model. The results show that the hot-deformed activation energy Q is calculated to be 410.172 kJ/mol, the ratio of critical strain (εc) to peak strain (εp) is a constant value of about 0.67. The predicted stress obtained by the established constitutive equations matches well with the true stress from experimental data. Despite large errors occur at the stage where strain rate is 0.1 s^-1 and the values of true strain are less than 0.1, the stage of large strain should be more concerned during plastic forming. Furthermore, the predicting accuracy with the DRX kinetics model was testified by an electron back-scattered diffraction (EBSD) technique.

关键词： Ti-22Al-25Nb hot deformation constitutive relation EBSD technique

Cellular automaton simulation of dynamic recrystallization behavior in V-10Cr-5Ti alloy under hot deformation conditions

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Transactions of Nonferrous Metals Society of China 2019年第1期29卷 98-111页

作者： Zhuo-han CAO Yu SUN Chen ZHOU Zhi-peng WAN Wen-hua YANG Li-li REN lian-xi hu National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China Institute of Machinery Manufacturing Technology China Academy of Engineering Physics Mianyang 621900 China China Nuclear Industry No. 23 Construction Co. Ltd. Beijing 101300 China

The deformation behavior of V-10Cr-5Ti alloy was studied on the Gleeble-1500 thermomechanical simulator at the temperatures of 950-1350℃, and the strain rates of 0.01-10 s^-1. Based on the Arrhenius model, dislocation density model, nucleation model and grain growth model, a numerical cellular automaton (CA) model coupling simulation of hot deformation is established to simulate and characterize the microstructural evolution during DRX. The results show that the flow stress is fairly sensitive to the strain rate and deformation temperature. The error between the predicted stress by the Arrhenius model and the actual measured value is less than 8%. The initial average grain size calculated by the CA model is 86.25 μm, which is close to the experimental result (85.63 μm). The simulations show that the effect of initial grain size on the dynamic recrystallization microstructure evolution is not significant, while increasing the strain rate or reducing the temperature can refine the recrystallized grains.

关键词： V-10Cr-5Ti alloy hot deformation dynamic recrystallization cellular automaton microstructure numerical simulation grain refinement

Photo‑Energized MoS_(2)/CNT Cathode for High‑Performance Li–CO_(2)Batteries in a Wide‑Temperature Range

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Nano-Micro Letters 2025年第1期17卷 160-175页

作者： Tingsong hu Wenyi lian Kang hu Qiuju Li Xueliang Cui Tengyu Yao Laifa Shen Jiangsu Key Laboratory of Materials and Technologies for Energy Storage College of Materials Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016People’s Republic of China

Li–CO_(2) batteries are considered promising energy storage systems in extreme environments such as Mars;however,severe performance degradation will occur at a subzero temperature owning to the sluggish reaction ***,a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO_(2) battery was achieved with a binder-free MoS_(2)/carbon nanotube(CNT)photo-electrode as *** unique layered structure and excellent photoelectric properties of MoS_(2) facilitate the abundant generation and rapid transfer of photo-excited carriers,which accelerate the CO_(2) reduction and Li_(2)CO_(3) decomposition upon *** illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V,attaining superior energy efficiency of 90.2%and excellent cycling stability of over 120 *** at an extremely low temperature of−30℃,the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS_(2)/CNT *** work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO_(2) battery in addressing the obstacle of charge overpotential and energy efficiency.

关键词： Li-CO_(2)batteries Photo-energized Wide operation-temperature Kinetics MoS_(2)

Microstructure and mechanical properties of AZ61 magnesium alloy prepared by repetitive upsetting-extrusion

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Transactions of Nonferrous Metals Society of China 2015年第2期25卷 381-388页

作者：徐岩胡连喜孙宇贾建波姜巨福马庆国哈尔滨工业大学材料科学与工程学院哈尔滨150001 北华大学机械工程学院吉林132021 深圳平津有限公司深圳518000

The process of repetitive upsetting-extrusion （RUE） was used to achieve severe plastic deformation （SPD） for an as-cast AZ61 magnesium alloy in temperature range of 285-380 ℃. The microstructure and mechanical properties of the as-cast and RUE processed AZ61 alloys were investigated. The results indicated that homogeneous fine-grained structure with mean grain size of 3.5 μm was obtained as the accumulated true strain in the axial direction increased to 4.28 after three RUE passes at 285 ℃. The dominant reason of grain refinement was considered the dynamic recrystallization induced by strain localization. It was also found that the microstructural evolution was affected by temperature and accumulated deformation. The mechanical properties of RUE processed AZ61 alloys were significantly improved owing to grain refinement. Furthermore, the relationship between deformation parameters and mechanical properties of AZ61 alloy prepared by RUE processing was revealed by tensile tests carried out at room temperature.

关键词： AZ61 magnesium alloy repetitive upsetting-extrusion severe plastic deformation groin refinement mechanicalproperties

EC细网格10m风场产品在渤、黄海海域的预报能力检验与评估

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海洋预报 2020年第6期37卷 74-82页

作者：连喜虎刘桂艳高松王彬白志鹏国家海洋局北海预报中心山东青岛266033 中国人民解放军61741部队北京100083

基于ECMWF(EC)细网格的24 h、48 h和72 h预报的10 m风场资料,与选取的渤、黄海海域9个浮标的10 m实测风速和风向进行对比检验。结果表明:(1)EC细网格24 h预报的10 m风速与各浮标站的实测风速预报偏差中位数在0.11~0.52 m/s之间,EC预报的... 详细信息

基于ECMWF(EC)细网格的24 h、48 h和72 h预报的10 m风场资料,与选取的渤、黄海海域9个浮标的10 m实测风速和风向进行对比检验。结果表明:(1)EC细网格24 h预报的10 m风速与各浮标站的实测风速预报偏差中位数在0.11~0.52 m/s之间,EC预报的10 m风速在渤、黄海海区预报结果总体略偏大,但在黄海中部预报效果优于渤海和黄海北部海区;(2)EC细网格预报的10 m风速与实测风速相关性较好,选取的9个浮标站中8个浮标站的24 h预报风速和实测风速相关系数达到0.85以上,预报偏差离散度小,预报效果较好;(3)不同风速条件下,EC细网格的5级风预报结果与实测风速最为接近,对大于5级风的预报结果偏小,而小于5级风的预报结果偏大;风速越小,风向预报偏差样本的离散度越大。不同风向条件下,各向的24 h预报风向平均偏差在-20°~12°之间,48 h和72 h平均偏差分别为-22°~14°和-20°~15°之间,24 h预报风向结果优于48 h和72 h预报风向。在实况为偏北向风时,风向平均偏差较大,实况为偏南向风时,风向平均偏差较少。

关键词： 10m风 EC细网格平均偏差相关系数

基于长期浮标观测资料与数值模式的渤海潮流性质研究

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中国海洋大学学报（自然科学版） 2015年第6期45卷 7-11页

作者：高松徐江玲连喜虎王海棠李锐国家海洋局北海预报中心山东青岛266061 山东省海洋防灾减灾重点实验室山东青岛266061 国家海洋局北海海洋工程勘察研究院山东青岛266061

基于渤海7个大型浮标各近1年的海流观测资料,结合采用FVCOM模式建立的渤海潮汐潮流模式,对渤海的潮流性质进行分析,并将结果与1992年版海洋图集进行比较。结果表明:辽东湾、渤海湾属规则半日潮流;莱州湾的大部属规则半日潮流,小部分为... 详细信息

基于渤海7个大型浮标各近1年的海流观测资料,结合采用FVCOM模式建立的渤海潮汐潮流模式,对渤海的潮流性质进行分析,并将结果与1992年版海洋图集进行比较。结果表明:辽东湾、渤海湾属规则半日潮流;莱州湾的大部属规则半日潮流,小部分为不规则半日潮流;渤海中央及渤海海峡海域属不规则半日潮流;渤海海峡东南侧存在以烟台芝罘岛为中心的规则全日潮流向不规则半日潮流过渡区域。海洋图集中龙口附近海域的不规则全日潮流类型区并不存在;莱州湾湾底东部的不规则半日潮流区为规则半日潮流类型。

关键词：渤海潮流性质海流资料数值模拟

我国少数民族女性权利保障研究——以人权法平等原则为视角

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陕西行政学院学报 2017年第3期31卷 11-15页

作者：邓喜莲胡芝春湖北文理学院湖北襄阳441053 湖北省襄阳市襄州区检察院湖北襄阳441053

由人权法中的平等原则视角出发,当前我国少数民族女性的政治、经济与社会等基本权利都得不到充分保障,其根源在于法律制度、政策上过于强调权利保障上的"形式平等"。因此,有必要通过实施优惠措施、均衡资源分配、构建法律政策性别平等... 详细信息

由人权法中的平等原则视角出发,当前我国少数民族女性的政治、经济与社会等基本权利都得不到充分保障,其根源在于法律制度、政策上过于强调权利保障上的"形式平等"。因此,有必要通过实施优惠措施、均衡资源分配、构建法律政策性别平等评估机制来实现少数民族女性权利保障上的"实质平等"。

关键词：少数民族女性权利人权保障平等原则