检索结果-南通市图书馆

Interactive effect of thermal aging and proton irradiation on microstructural evolution and hardening ofδ-ferrite in 308L stainless steel weld metal

引用

Journal of Materials Science & Technology 2024年第3期170卷 140-155页

作者： Xiaodong Gao Xiaodong Lin Tao Guo Lining Xu Yaolei Han Baolong Jiang Xingyuan Mei Qunjia Peng Lijie Qiao Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Institute of Materials Shanghai UniversityShanghai 200072China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Suzhou Nuclear Power Research Institute Suzhou 215004China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

In the harsh service environment of high temperature and intense neutron irradiation in water-cooled nuclear reactors,the austenitic stainless steel weld overlay cladding on the inner surface of the reactor pressure vessel suffers from thermal aging and irradiation damage simultaneously,which can induce microstructural evolution and hardening of the material.Since it is quite difficult to achieve this simul-taneous process out of the pile,two kinds of combined experiments,i.e.,post-irradiation thermal aging and post-aging irradiation were performed on 308 L stainless steel weld metals in this work.The interactive effect of thermal aging and proton irradiation on microstructural evolution and hardening ofδ-ferrite in 308 L weld metal was investigated by combining atom probe tomography,transmission elec-tron microscopy and nanoindentation tests.The results revealed that thermal aging could eliminate the dislocation loops induced by irradiation and affect the phase transition process by accelerating spinodal decomposition and G-phase precipitation,thus enhancing hardening of irradiatedδ-ferrite.For the effect of irradiation on the microstructure and hardening of thermally agedδ-ferrite,however,intensive collision cascades can intensify G-phase precipitation and dislocation loop formation but decrease spinodal decomposition,leading to a limited effect on hardening of thermally agedδ-ferrite.Furthermore,the interaction of thermal aging and irradiation can promote G-phase precipitation.Meanwhile,the interaction can causeδ-ferrite hardening,which is mainly influenced by spinodal decomposition,followed by G-phase and dislocation loops,where spinodal decomposition and G-phase cause hardening by inducing strain fields.

关键词： Austenitic stainless steel weld metals Thermal aging Proton irradiation Interaction microstructural evolution Hardening

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

microstructural evolution during Tensile Deformation in TRC-ZA21 Magnesium Alloy with Different Loading Directions and Strain Rates

引用

Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 192-214页

作者： Yun Zhang Chen Jiang Shaoheng Sun Wei Xu Quan Yang Yongjun Zhang Shiwei Tian Xiaoge Duan Zhe Xu Haitao Jiang Institute of Engineering Technology University of Science and Technology BeijingBeijing100083China China Electric Power Research Institute Beijing100055China Shunde Graduate School of University of Science and Technology Beijing Foshan528399China China Ship Research and Development Academy Beijing100081China

The variation of texture characteristics and activation of deformation mechanism in magnesium alloys can be achieved by addition of RE and Ca elements and subsequently affect the microstructure evolution during deformation process.In this manuscript,the effects of loading direction and strain rate on mechanical properties,microstructural characteristics,texture evolution and deformation mechanism in TRC-ZA21 magnesium alloy sheet were investigated.Moreover,orientation dependence and strain rate sensitivity of deformation mechanism were also discussed.The results showed that evident difference in mechanical properties in TRC-ZA21 alloy exhibited by the changes in loading direction and strain rate.The variations in grain orientation and basal texture characteristic were attributed to the grain rotation behavior during the plastic deformation,dominated by deformation mechanism.Basal slip,extension twinning and prismatic slip played different contributions to plastic deformation behavior and presented orientation dependence and strain rate sensitivity.The activities of prismatic slip and extension twinning both enhance with increasing strain rate.The phenomenon of weakened effect of twinning and promoted role of prismatic slip was presented to coordinate strain compatibility during plastic deformation.

关键词： Magnesium alloys Mechanical property Orientation behavior Deformation mechanism microstructural evolution

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

microstructural evolution and fracture mechanism of a new AlZn-Mg-Cu-Zr alloy processed by equal-channel angular pressing

引用

Rare Metals 2022年第10期41卷 3546-3551页

作者： Hong-Li Liu Ping Li Ke-Min Xue Chen-Hao Qian Rui Hua School of Materials Science and Engineering Hefei University of TechnologyHefei230009China

Equal-channel angular pressing(ECAP) is considered to be one of the most effective processing procedures to produce ultrafine-grained(UFG) materials.A new AI-ZnMg-Cu-Zr alloy was subjected to ECAP experiment in Route B_(C)(i.e.,rotated 90° in the same sense between each pass).The effect of ECAP on the microstructural evolution and fracture mechanism of the alloy was analyzed by optical microscope(OM),X-ray diffraction(XRD),tensile test(at room temperature),and scanning electron microscope(SEM).The results show that the main strengthening phase of the alloy is MgZn_(2),whose content increases apparently after ECAP,the dislocation density increases by one order of magnitude,the hardness value of the 1 pass ECAPed sample increases by 53 %,the ultimate tensile strength(UTS)increases by 29 %,and the true strain increases by 15.4 %.But the further increase in the strength with the passes increasing would cost a slight drop in the true strain.The morphology of the tensile dimples is converted from elongated one to equiaxed one with a uniform distribution of size and depth after pressing.

关键词： Al-Zn-Mg-Cu-Zr alloy Equal-channel angular pressing microstructural evolution Crystallite size Mechanical properties Fracture mechanism

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

microstructural evolution of polymer-derived hexagonal boron nitride fibres under high-temperature stretching

引用

Journal of Advanced Ceramics 2023年第10期12卷 1973-1988页

作者： Zhiguang Wang Min Ge Shouquan Yu Xiaoming Sun Xueli Qi Hao Zhang Wen Xiao Weigang Zhang University of Chinese Academy of Sciences Beijing 100080China Key Laboratory of Science and Technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 100080China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341119China Shandong Industrial Ceramics Research and Design Institute Zibo 255000China

High-temperature stretching plays a crucial role in enhancing the performance of fibres,while a quantitative investigation into the impacts of tension and stretching duration on the microstructure and performance of hexagonal boron nitride(h-BN)fibres remains absent.In this study,to elucidate the microstructural evolution of the h-BN fibres under thermal stretching,amorphous BN fibres were heated at 2000℃under tension of 30,50,and 70 N for 1,3,and 5 h in a nitrogen atmosphere.Subsequently,the grain size,pore structure,orientation degree,microscopic morphology,and mechanical properties were analysed at room temperature.The results show that high-temperature stretching enhances the orientation degree of the BN fibres,consequently elevating Young’s modulus.The maximum orientation degree of the BN fibres was 86%,aligning with a corresponding Young’s modulus of 206 GPa.Additionally,high-temperature stretching enlarged the sizes of grains and pores,a fact substantiated by the radial cracking of the fibres upon extending thermal stretching time.Owing to the expanded pore structure of the BN fibres and the inability to form a sufficiently strong“card structure”between shorter microfibre bundles,the tensile strength of the BN fibres did not increase continually,reaching a maximum of 1.0 GPa.microstructural observations revealed that the BN fibres,composed of highly oriented lamellar h-BN grains,tend to form radial textures under high-tensile thermal stretching and onion-skin textures under prolonged thermal stretching.These findings offer a theoretical foundation for the preparation of high-performance h-BN fibres.

关键词： polymer-derived ceramics boron nitride fibres microstructural evolution high-temperature stretching

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Systematic analysis of distinct flow characteristics and underlying microstructural evolution mechanisms of a novel fine-grained P/M nickel-based superalloy during isothermal compression

引用

Journal of Materials Science & Technology 2023年第31期162卷 57-73页

作者： Hongning Wen Junsong Jin Xuefeng Tang Xinyun Wang Heyang Yang Yiding Zhang Lei Deng Pan Gong Qingsong Wei Yingjie He Jianzheng Guo State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Shenzhen Wedge Central South Research Institute Co. Ltd.Shenzhen 518000China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Isothermal forging(IF)is an effective method for forming difficult-to-deform materials like P/M superalloys.Understanding the isothermal compression microstructural evolution mechanism of a novel P/M s-peralloy provides the basis for its optimized IF planning.In this study,the isothermal compression tests of a novel fine-grained P/M nickel-based superalloy were carried out at 1000-1150℃with strain rates of 0.001-0.01 s^(−1).The results indicated that the alloy exhibits three distinct flow characteristics:continuous softening after reaching the peak stress,near-steady superplastic flow,and discontinuous hardening,corresponding to different strain rate sensitivity exponent(m)values.Varied microstructural evolution mechanisms,including grain boundary sliding(GBS),dynamic recrystallization(DRX),and grain growth,are dominated in different m-value domains.Meanwhile,different roles of primaryγ’play in microstruc-tural evolution were clarified.A moderate fraction of primaryγ’with 8.5%-14.2%can well coordinate the GBS and hinder excessive grain growth at a high m value domain(m>0.4).When 0.2

关键词： P/M nickel-based superalloy Flow characteristic microstructural evolution Superplastic flow Dynamic recrystallization

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insight into the microstructural evolution of anthracite during carbonization-graphitization process from the perspective of materialization

引用

International Journal of Mining Science and Technology 2022年第6期32卷 1397-1406页

作者： Huihui Zeng Baolin Xing Yijun Cao Bing Xu Lei Hou Hui Guo Song Cheng Guangxu Huang Chuanxiang Zhang Qi Sun Henan Key Laboratory of Coal Green Conversion College of Chemistry and Chemical EngineeringHenan Polytechnic UniversityJiaozuo 454003China State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization Jiaozuo 454003China Henan Province Industrial Technology Research Institute of Resources and Materials Zhengzhou UniversityZhengzhou 450001China National Engineering Research Center of Coal Preparation and Purification China University of Mining and TechnologyXuzhou 221116China

Materialization of coal is one of effective and clean pathways for its utilization. The microstructures of coal-based carbon materials have an important influence on their functional applications. Herein, the microstructural evolution of anthracite in the temperature range of 1000–2800 ℃ was systematically investigated to provide a guidance for the microstructural regulation of coal-based carbon materials.The results indicate that the microstructure of anthracite undergoes an important change during carbonization-graphitization process. As the temperature increases, aromatic layers in anthracite gradually transform into disordered graphite microcrystals and further grow into ordered graphite microcrystals, and then ordered graphite microcrystals are laterally linked to form pseudo-graphite phase and eventually transformed into highly ordered graphite-like sheets. In particular, 2000–2200 ℃ is a critical temperature region for the qualitative change of ordered graphite crystallites to pseudo-graphite phase,in which the relevant structural parameters including stacking height, crystallite lateral size and graphitization degree show a rapid increase. Moreover, both aromaticity and graphitization degree have a linear positive correlation with carbonization-graphitization temperature in a specific temperature range.Besides, after initial carbonization, some defect structures in anthracite such as aliphatic carbon and oxygen-containing functional groups are released in the form of gaseous low-molecular volatiles along with an increased pore structure, and the intermediates derived from minerals could facilitate the conversion of sp^(3) amorphous carbon to sp^(2) graphitic carbon. This work provides a valuable reference for the rational design of microstructure of coal-based carbon materials.

关键词： Anthracite microstructural evolution Carbonization-graphitization Graphite microcrystals Materialization

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Probing microstructural evolution in weld metals subjected to varied CaF_(2)-TiO_(2) flux cored wires under high heat input electro-gas welding

引用

Journal of Iron and Steel Research(International) 2023年第1期30卷 150-157页

作者： Xu Xie Ming Zhong Tan Zhao Cong Wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China State Key Laboratory of Metal Material for Marine Equipment and Application Ansteel Co.Ltd.Anshan 114021LiaoningChina

Fused CaF_(2)-TiO_(2) fluxes have been designed,prepared,and applied in the flux cored wires to join EH36 shipbuilding steels under high heat input electro-gas welding.Ensuing microstructural evolution in the weld metals subjected to varied CaF_(2)-TiO_(2) flux cored wires has been fully documented.It has been demonstrated that as the content of TiO2 in the fused fluxes increases,columnar grain size increases,and major constituents in the weld metal change from lath bainite,to granular bainite,and then to acicular ferrite.Such phenomena are elucidated via salient chemical reactions involving oxygen pickup and concurrent titanium transfer.

关键词： microstructural evolution Elemental variation Electro-gas welding High heat input Shipbuilding steel

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Mechanical properties and microstructural evolution of rheocast A356 semi-solid slurry prepared by annular electromagnetic stirring

引用

China Foundry 2023年第4期20卷 315-328页

作者： Mohammad Taghi Asadi Khanouki Department of Materials and Metallurgy Engineering Shahid Bahonar University of KermanP.O.Box ***KermanIran Mineral Industries Research Center(MIRC) Shahid Bahonar University of KermanP.O.Box ***KermanIran

Nowadays,having an effective technique in preparing semi-solid slurries for rheocasting process seems to be an essential requirement.In this study,semi-solid slurry of A356 aluminum alloy was prepared by three-phase annular electromagnetic stirring(A-EMS)technique under different conditions.The effects of stirring current,pouring temperature and stirring time on microstructural evolution,mean particle size,shape factor and solid fraction were investigated.The rheocasting process was carried out by using a drop weight setup and to inject the prepared semi-solid slurry in optimal conditions into the step-die cavity.The filling behavior and mechanical properties of parts were studied.microstructural evolution showed that the best semi-solid slurry which had fine spherical particles with the average size of~27μm and a shape factor of~0.8 was achieved at the stirring current of 70 A,melt pouring temperature of 670℃,and stirring time of 30 s.Under these conditions,the step-die cavity was completely filled at die preheating temperature of 470℃.The hardness increases by decreasing step thickness as well as die preheating temperature.Moreover,the tensile properties are improved at lower die preheating temperatures.The fracture surface,which consists of a complex topography,indicates a typical ductile fracture.

关键词： semi-solid slurry annular electromagnetic stirring rheocast A356 aluminum alloy microstructural evolution mechanical properties magnetic flux density

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The effects of orientation control via tension-compression on microstructural evolution and mechanical behavior of AZ31 Mg alloy sheet

引用

Journal of Magnesium and Alloys 2022年第2期10卷 446-458页

作者： Qingshan Yang Bin Jiang Bo Song Zujian Yu Dewei He Yanfu Chai Jianyue Zhang Fusheng Pan School of Metallurgy and Material Engineering Chongqing University of Science and TechnologyChongqing 401331China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China School of Materials and Energy Southwest UniversityChongqing400715China MagIC–Magnesium Innovation Centre Helmholtz-Zentrum GeesthachtMax-Planck-Straße 1Geesthacht 21502Germany School of Engineering Technology Purdue UniversityWest LafayetteIN 47907-2021United States

The grain orientation control via twinning activity on deformation features is of great significance to offer a key insight into understanding the deformation mechanism of Mg alloy sheets.The{10–12}twinning were performed by pre-strain paths,i.e.,tension(6%)and compression(5%)perpendicular to the c-axis along extrusion direction(ED),to investigate the microstructural evolution and mechanical properties of AZ31 Mg alloy sheets.The distinction in the texture evolution and strain hardening behavior was illustrated in connection with the pre-strain paths for the activities of twinning and slip.The result shows that the activation of the deformation mode was closely bound up with the grain orientation and the additional applied load direction.The{10–12}twin-texture components with c-axis//ED were generated by precompression,which can provide an appropriate alternative to accommodate the thin sheet thickness strain and enhance the room temperature formability of Mg alloy sheet.

关键词： Mg alloy Orientation control microstructural evolution Texture Stretch formability

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Modeling of microstructural evolution and flow behavior of superalloy IN718 using physically based internal state variables

引用

Rare Metals 2022年第8期41卷 2759-2766页

作者： Xue-Feng Tang Bao-Yu Wang Ning Zhang Yuan-Ming Huo Jing Zhou School of Mechanical Engineering University of Science and Technology BeijingBeijing100083China Beijing Aeronautical Manufacturing Technology Research Institute Beijing100024China

microstructural evolution and flow behavior greatly affect the hot forming process of IN718.In this research,hot deformation behaviors of IN718 were investigated by performing hot compression tests at temperature range of 1000-1100℃with strain rates of 0.1-20.0 s^(-1).By incorporating physically based internal state variables such as dislocation density,volume fraction of dynamic recrystallization,and grain size,a set of unified viscoplastic constitutive equations were developed to predict the microstructural evolution and flow behavior of IN718.The material constants were determined using a genetic algorithm(G A)-based optimization method.Comparisons of the computed and experimental results indicate that the constitutive equations established in this study can accurately describe the hot deformation behavior and microstructural evolution of IN718.

关键词： IN718 microstructural evolution Flow behavior Constitutive equations Internal state variables

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：