检索结果-南通市图书馆

Assessing the predictive capabilities of precipitation Strengthening models for deformation twinning in Mg alloys using phase-field simulations

引用

Journal of Magnesium and Alloys 2023年第12期11卷 4525-4541页

作者： Darshan Bamney Laurent Capolungo Materials Science&Technology Division Los Alamos National LaboratoryUSA

Precipitation Strengthening is a key strategy for improving the overall mechanical properties of Mg alloys. In Mg-Al alloys, basal precipitates are known to strengthen against twinning, resulting in an increase in the critical resolved shear stress(CRSS) necessary for continued deformation. Although several models have been proposed to quantify the influence of precipitate shape, size, and distribution on the CRSS, the accuracy, scope, and applicability of these models has not been fully assessed. Accordingly, the objectives of this study are:(i)to analyze the accuracy of analytical models proposed in the literature for precipitation Strengthening against twin thickening and propagation(in Mg-Al alloys) using phase-field(PF) simulations,(ii) to propose modifications to these model forms to better capture the observed trends in the PF data, and(iii) to subsequently test the predictiveness of the extended models in extrapolating to experimental Strengthening data.First, using an atomistically-informed phase-field method, the interactions between migrating twin boundaries(during the propagation and thickening stages) and basal plates are simulated for different precipitate sizes and arrangements. In general, comparison of the increase in CRSS determined from the PF simulations and the predictions from four precipitation Strengthening models reveals that modifications are necessary to the model forms to extend their applicability to precipitation Strengthening against both twin thickening and propagation. A subsequent comparison between predictions from the extended models and experimental Strengthening data for peak age-hardened samples reveals that the(extended) single dislocation and dislocation wall models provide reasonably accurate values of the increase in CRSS.Ultimately, the results presented here help elucidate the fidelity and applicability of the various hardening models in predicting precipitation strenghtening effects in technologically important alloys.

关键词： Twinning Twin precipitate interactions Strengthening Magnesium alloys Phase field Mechanical behavior

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

Strengthening and control of second-phase particle precipitation in ferritic/austenitic/martensitic heat-resistant alloys:a review

引用

Journal of Iron and Steel Research(International) 2024年第1期31卷 3-23页

作者： Xue-cheng Peng Han-jie Guo Xin-fang Zhang Yi-wa Luo Ye Sun Jing Guo Rong-guang Yang Xiao-dan Zheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials University of Science and Technology Beijing(USTB)Beijing100083China Beijing Shougang Gitane New MATERIALS Co. Ltd.Beijing102206China

Heat-resistant alloys with excellent mechanical properties are widely used in various fields,and further improvement in their properties is essential to meet the requirements in new-generation advanced supercritical boilers,nuclear reactors,superheaters,and other new materials applications.To effectively enhance the comprehensive performance of heat-resistant alloys,second-phase particle Strengthening has been widely studied,and in the face of different service envi-ronments of advanced heat-resistant steels,the selection of suitable second-phase particles is essential to maximize the performance of these alloys.To this end,three major types of reinforcing phases in heat-resistant alloys such as carbides,rare earth oxides,and intermetallic compounds are summarized.A comparative analysis of the precipitation behavior of the reinforcing phases with different types as well as the risks and means of controlling their use in service,is presented.Key parameters for the application of various types of second-phase particles in heat-resistant alloys are provided to support the design and preparation of new ultrahigh-performance heat-resistant alloys.

关键词： Heat-resistant alloy Second-phase particle Carbide Rare earth oxide Intermetallic compound Strengthening

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

Strengthening in gradient TiAl alloys

引用

Journal of Materials Science & Technology 2023年第35期166卷 98-105页

作者： P.Li Y.Chen X.Liu X.H.Wang F.R.Chen Z.X.Qi G.Zheng H.G.Xiang G.Chen National Key Laboratory of Advanced Casting Technologies MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials TechnologyEngineering Research Center of Materials Behavior and DesignMinistry of EducationNanjing University of Science and TechnologyNanjing210094China

Gradient structure is emerging as an effective strategy to fabricate metals with remarkable mechanical performance,but have not been verified in intermetallic compounds for high-temperature applications.Through experiments and atomic simulations,we show that a typical intermetallic TiAl alloy with gra-dient structure has a significant Strengthening effect both at room temperature and high temperatures.The room-temperature compressive strength of TiAl alloys with gradient grain obtained by additive man-ufacturing is 2.57 GPa,which is∼2.7 times as strong as that with equiaxed grain.The Strengthening effect is attributed to more sessile dislocations in gradient structure caused by the intersections of mul-tiple slip systems in gradient grain.More importantly,the Strengthening effect is still effective at high temperatures and the compressive strength is 1.28 GPa at 750°C.The simulation results show that this Strengthening effect is due to the increased Hirth dislocation at high temperatures.This study expands the applications of TiAl alloys for load-bearing structures and provides a new strategy for improving the strength of intermetallic compounds at both room temperature and high temperatures.

关键词： TiAl alloys Strengthening Gradient grain Additive manufacturing Molecular dynamics

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

A new Strengthening mechanism driven by disruptive shear and solute segregation during warm rolling in 1.4 GPa class 12.5 wt% Al added-FeMnC ultra-lightweight steel

引用

Journal of Materials Science & Technology 2023年第26期157卷 174-188页

作者： Chiwon Kim Hyun-Uk Hong Joonoh Moon Bong Ho Lee Seong-Jun Park Chang-Hoon Lee Department of Materials Convergence and System Engineering Changwon National University 20 Changwondaehak-roChangwonGyeongnam 51140Republic of Korea Advanced Analysis Team Daegu Gyeongbuk Institute of Science and Technology 333 Technojungang-daeroDaegu42988Republic of Korea Ferrous Alloy Department Korea Institute of Materials Science 797 ChangwondaeroChangwonGyeongnam 51508Republic of Korea

Novel Strengthening of Fe-29.1Mn-12.5Al-1.35C-4.95Cr steel achieved by warm rolling was investi-gated.The solution-treated steel consisted of aγ-matrix containing nano-sizedκ-carbide((Fe,Mn)_(3) AlC)and elongated prior ferrite,which was transformed into FeAl-type B2 and Fe_(3) Al-type D0_(3) phases.The solution-treated steel exhibited poor strain hardening owing to glide softening associated withκ-carbide shearing by dislocations.However,after warm rolling with a reduction ratio of 30%at 300℃,the yield and tensile strengths significantly increased from 917 to 1300 MPa and 1025 to 1419 MPa,respectively.The tensile test conducted at 300℃to simulate warm rolling exhibited serrated flows,indicating dy-namic strain aging(DSA).Atom probe tomography exhibited that the C atoms inκ-carbide were swept away along the slip direction by disruptive shear during rolling at 300℃.The swept C atoms along the slip direction interacted strongly with dislocations at 300℃,with repeated pinning and breakaway of dislocations from the C atoms.This contributed to significant Strengthening owing to the formation of a solute-rich atmosphere after warm rolling.The results of the tensile tests at 300℃indicated that the de-gree of Strengthening was proportional to the pre-strain level.Tensile strength of 1.4 GPa can be achieved with good ductility(17%elongation)by warm rolling.This novel warm-rolling Strengthening method ex-pedites the potential application of Fe-29.1Mn-12.5Al-1.35C-4.95Cr as a 1.4 GPa class ultra-lightweight steel.

关键词： FeMnAlC Cr addition κ-carbide Dynamic strain aging Strengthening

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

Effect of modifying matrix microstructures and nanosized precipitates on Strengthening mechanisms and ductile-to-brittle-transitiontemperature in a 1000 MPa Ni-Cr-Mo-Cu steel

引用

Journal of Iron and Steel Research(International) 2022年第8期29卷 1257-1276页

作者： Fei Zhu Li Yang Feng Chai Xiao-bing Luo Cai-fu Yang Zheng-yan Zhang Department of Structural Steels Central Iron and Steel Research InstituteBeijing 100081China Material Digital R&D Center China Iron and Steel Research Institute GroupBeijing 100081China

A superior combination of yield strength(1001 MPa)and-20℃ impact toughness(166 J)was obtained in Nb-V-Timicroalloyed Ni-Cr-Mo-Cu steel treated by direct quenching and tempering route(DQT).The tested steels treated by DQT route and re-austenitization and tempering route(QT)were compared with each other in terms of mechanical properties and microstructures characterized by optical microscopy,transmission electron microscopy,X-ray diffraction,electron back-scattered diffraction method and so on.Strength and Vickers hardness of the tested steel treated by the above two routes vary with isothermal aging temperature(400-600℃),shown as under-aged state,peak-aged state and overaged state.All DQT specimens show higher strength and Vickers hardness than QT specimens with the same aging condition.Furthermore,the largest difference of yield strength between DQT and QT specimens was shown in DQT600 and QT600 specimens.DQT600 or QT600 specimens refers to direct quenched(DQ)or quenched(Q)specimens isothermally aged at 600℃.The main disparities in quenched microstructure between DQ and Q specimens are mainly in morphology of prior austenite grains,dislocation density of martensite matrix and solution amount of Nb and Mo elements dissolving in martensite matrix,which play key roles in affecting microstructure and mechanical properties of DQT and QT specimens.Higher dislocation density of matrix and finer average diameter of both MC(M is any combination of Nb,Mo and V)and Cu-rich particles were shown in DQT600 specimens than in QT600 specimens.Strengthening from dislocations and nanosized MC and Cu-rich particles mainly leads to the largest difference of yield strength between DQT600 and QT600 specimens.In addition,strong dislocation Strengthening and precipitation Strengthening in DQT600 specimen also elevated its ductile-to-brittle-transition-temperature,compared with QT600 specimen.

关键词： Cu-bearing high-strength low-alloy steel Direct quenching Nanosized precipitate Strengthening Ductile-to-brittle-transition-temperature

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

On the Strengthening and slip activity of Mg-3Al-1Zn alloy with pre-induced{1012¯}twins

引用

Journal of Magnesium and Alloys 2023年第4期11卷 1292-1307页

作者： Jie Kuang Yuqing Zhang Xinpeng Du Jinyu Zhang Gang Liu Jun Sun State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049P.R.China The College of Optics&Photonics University of Central FloridaOrlandoFL 32826United States

{1012¯}twins were introduced into the magnesium(Mg)plate AZ31 via pre-rolling along its transverse direction.The plates,both with and without the pre-induced{1012¯}twins,were subjected to uniaxial tension along different directions.Using crystal plasticity modeling,we found that the Strengthening effect of the pre-induced{1012¯}twins on the macroscopic flow stress primarily arised from the increased slip resistance caused by the boundaries,rather than the orientation hardening due to the twinning reorientation(although the latter did make its contribution in some specific loading directions).Besides,the pre-existing{1012¯}twins were found,by both experiments and simulation,to promote the activity of prismatic and pyramidalin the parent matrix of the material.Further analysis showed that the enhanced non-basal slip activity is related to the{1012¯}twin boundaries’low micro Hall-Petch slope ratios of non-basal slips to basal slip.With the critical resolved shear stress(CRSS)obtained from crystal plasticity modeling and the orientation data from EBSD,a probability-based slip transfer model was proposed.The model predicts higher slip transfer probabilities and thus lower strain concentration tendencies at{1012¯}twin boundaries than that at grain boundaries,which agrees with the experimental observation that the strain localization was primarily associated with the latter.The present findings are helpful scientifically,in deepening our understanding of how the pre-induced{1012¯}twins affect the strength and slip activity of Mg alloys,and technologically,in guiding the design of the pre-strain protocol of Mg alloys.

关键词： Mg alloy {1012¯}twins Strengthening Slip activity Micro Hall-Petch effect

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

Recent advances in chemical durability and mechanical stability of superhydrophobic materials: Multi-strategy design and Strengthening

引用

Journal of Materials Science & Technology 2022年第34期129卷 40-69页

作者： Peng Wang Changyang Li Dun Zhang Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100039China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Inspired by the lotus leaf effect, non-wetting artificial superhydrophobic surfaces demonstrate an enormous potential in numerous fields. However, limited by poor stability and durability, superhydrophobic surfaces are rarely available for practical applications. In this review, based on the wettability mechanisms and failure modes of superhydrophobic surfaces, it is proposed that the construction of highly stable superhydrophobic materials can be approached from four aspects, including structural design, chemical bonding, interfacial-Strengthening of hydrophobic materials and substrates, and self-healing. We introduced in detail the design ideas, Strengthening approaches, and characterization tools of highly stable superhydrophobic materials from the perspective of multi-strategy design and Strengthening, and provided corresponding insights. Eventually, the development, current status, and prospects of highly stable and multifunctional superhydrophobic materials were also presented in detail. Recent advances and development prospects of durable superhydrophobic materials were summarized and discussed in this review,providing certain insights and design guidelines for the fabrication of stable superhydrophobic materials.

关键词： Superhydrophobicity Stability Durability Strengthening

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

Uncovering the softening mechanism and exploring the Strengthening strategies in extremely fine nanograined metals:A molecular dynamics study

引用

Journal of Materials Science & Technology 2022年第14期109卷 186-196页

作者： H.R.Peng Z.Y.Jian C.X.Liu L.K.Huang Y.M.Ren F.Liu School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The strength of polycrystalline metals increases with decreasing grain size,following the classical HallPetch relationship.However,this relationship fails when softening occurs at very small grain sizes(typically less than 10 to 20 nm),which limits the development of ultrahigh-strength materials.In this work,using columnar-grained nanocrystalline Cu-Ag‘samples’,molecular dynamics simulations were performed to investigate the softening mechanism and explore the Strengthening strategies(e.g.,formation of solid solution or grain boundary(GB)segregation)in extremely fine nanograined metals.Accordingly,the softening of pure metals is induced by atomic sliding in the GB layer,rather than dislocation activities in the grain interior,although both occur during deformation.The solid solution lowers the stacking fault energy and increases the GB energy,which leads to the softening of NC metals.GB segregation stabilizes GB structures,which causes a notable improvement in strength,and this improvement can be further enhanced by optimizing the solute concentration and GB excess.This work deepens the understanding of the softening mechanism due to atomic sliding in the GB layer and the Strengthening mechanism arising from tailoring the GB stability of immiscible alloys and provides insights into the design of ultrahighstrength materials.

关键词： Softening Strengthening Cu-Ag alloy Molecular dynamics Nanocrystalline

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

Shear strength model of the reinforced concrete beams with embedded through-section Strengthening bars

引用

Frontiers of Structural and Civil Engineering 2022年第7期16卷 843-857页

作者： Linh Van Hong BUI Phuoc Trong NGUYEN Faculty of Civil Engineering Ho Chi Minh City Open UniversityHo Chi Minh City 700000Vietnam

In this study,finite element(FE)analysis is utilized to investigate the shear capacity of reinforced concrete(RC)beams strengthened with embedded through-section(ETS)bars.Effects of critical variables on the beam shear strength,including the compressive strength of concrete,stiffness ratio between ETS bars and steel stirrups,and use of ETS Strengthening system alone,are parametrically investigated.A promising method based on the bond mechanism between ETS Strengthening and concrete is then proposed for predicting the shear resistance forces of the strengthened beams.An expression for the maximum bond stress of the ETS bars to concrete is developed.This new expression eliminates the difficulty in the search and selection of appropriate bond parameters from adhesion tests.The results obtained from the FE models and analytical models are validated by comparison with those measured from the experiments.Consequently,the model proposed in this study demonstrates better performance and more accuracy for prediction of the beam shear-carrying capacity than those of existing models.The results obtained from this study can also serve researchers and engineers in selection of the proper shear strength models for design of ETS-strengthened RC beams.

关键词： embedded through-section Strengthening fiber-reinforced polymer finite element shear strength model bond mechanism

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

Unraveling precipitation evolution and Strengthening function of the Al-Zn-Mg-Cu alloys with various Zn contents:Multiple experiments and integrated internal-state-variable modeling

引用

Journal of Materials Science & Technology 2022年第21期116卷 130-150页

作者： Jie Tang Mingcai Liu Guowei Bo Fulin Jiang Chunhui Luo Jie Teng Dingfa Fu Hui Zhang College of Materials Science and Engineering Hunan UniversityChangsha 410082China Department of Mechanical Engineering Technical University of MunichMünchen 80333Germany Swerim AB Stockholm 16407Sweden

Zn content is one of the most concerned factors in the development of next generation ultra-strength Al-Zn-Mg-Cu alloys owing to its essential role in precipitation Strengthening.In the present work,the underlying functions of Zn content in precipitation evolution and Strengthening function of Al-Zn-Mg-Cu alloys were systematically investigated by combining multiple experiments and an integrated internalstate-variable model.The experimental results indicated that the increased Zn content in Al-Zn-Mg-Cu alloys would promote the development of precipitates and enhance aging hardening.The diffusion flux of soluble Zn and the coordination of Mg atom controlled the crystallographic microstructures evolution during precipitates nucleation,growth and transition processes.By integrating precipitation development with electrical resistivity and hardness evolutions,an improved internal-state-variable physical model was then developed for the aging responses of Al-Zn-Mg-Cu alloys.The unified model considered the intrinsic characteristics of precipitates such as crystallographic orientation,morphology,component,and distribution.The specific improvements were to balance the combined functions of Zn element and Mg element and consider the plate-like morphology and directed growth as indicated by experiments.This model was also adaptive to heat-treatment variables and chemical compositions,and owned the notable advantages to simultaneously rationalize the observed microstructural characteristics,mechanical and electrical properties following artificial aging of Al-Zn-Mg-Cu alloys.In addition,a preliminary model framework between electrical resistivity and hardness for Al-Zn-Mg-Cu alloys was established.

关键词： Al-Zn-Mg-Cu alloys Precipitation Strengthening In situ electrical resistivity Modeling

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：