检索结果-内蒙古大学图书馆

3D Fe-Rich Phases Evolution and Its Effects on the Fracture Behavior of Al-7.0Si-1.2Fe Alloys by Mn Neutralization

Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 163-175页

作者： Dong-Fu Song Yu-Liang Zhao Zhi Wang Yi-Wang Jia Dao-Xi Li Ya-Nan Fu Da-Tong Zhang Wei-Wen Zhang National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou510641China Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou510650China School of Mechanical Engineering Dongguan University of TechnologyDongguan523808China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201204China

The evolution of the 3D Fe-rich phases of Al-7.0Si-1.2Fe alloys with different Mn contents was visualized and characterized using synchrotron X-ray computed tomography,and the effect of Fe-rich phases with typical morphologies on the fracture behavior during tensile testing was *** results showed that the Fe-rich phase changed from platelet-likeβ-Al_(5) Fe Si intoα-Al_(15)(Fe Mn)_(3)Si_(2)with various morphologies after the addition of *** Mn addition not only significantly reduced the volume fraction,equivalent diameter and interconnectivity of the Fe-rich phase but also greatly increased the sphericity,surface thickness,and distribution of the mean curvature and surface ***,the equivalent diameter ofα-Al_(15)(FeMn)_(3)Si_(2)had an inverse exponential function relationship with its *** 3D morphology ofα-Al_(15)(FeMn)_(3)Si_(2)can be summarized as massive and regular polyhedrons,hollow and regular polyhedrons,and multibranched *** fraction of the different 3D morphologies in each alloy is related to the Mn content,where excess Mn increased the number and volume fraction of the large Fe-rich particles with a low *** ductility of each alloy was significantly improved by the addition of Mn but gradually decreased when the Mn/Fe ratio exceeded *** increase in largeα-Al_(15)(Mn Fe)_(3)Si_(2)with a low sphericity was the main reason for the decreased ductility of alloys with a high Mn content.

关键词： Synchrotron X-ray tomography Fe-rich phase 3D morphology Fracture behavior

来源：评论

学校读者我要写书评

暂无评论

Research on high temperature deformation behavior and constitutive relation of TiAl alloy 3

Research on high temperature deformation behavior and consti...

引用

3rd International Conference on Advanced materials and Intelligent Manufacturing, ICAMIM 2022

作者： Li, Xiaoqiang Fan, Jiafeng Xu, Ganglai Hou, Jinbao Wang, Xuecheng Zhu, Zhencen Shao, Yonglin National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of Technology Guangzhou510640 China Aeronautical Key Laboratory for Welding and Joining Technologies AVIC Manufacturing Technology Institute Beijing100024 China

TiAl alloy is a new type of superalloy with great potential in aero-engine, and its hot deformation behavior has received extensive attention. In this study, the high temperature plastic deformation behavior of TiAl alloy has been studied through compression at 900 ∼1100 °C and strain rates of 0.1 s-1, 0.01 s-1, and 0.001s-1. Then, the constitutive model of TiAl alloy has been established based on the true stress-strain curve. The results show that TiAl alloy has a high sensitivity to strain rate and temperature at the experimental condition. Under the compression condition of 900 °C and 0.1 strain rate, the TiAl alloy has a penetrating crack when the strain reaches 0.6. The crack disappears as the temperature is increased and the strain rate is reduced. In addition, the plate organization in TiAl alloy breaks and spheroidizes after compression at 1100 °C. © Published under licence by IOP Publishing Ltd.

关键词： Strain rate

来源：评论

学校读者我要写书评

暂无评论

Effect of Solution and Aging Treatment on the Microstructure and Mechanical Properties of Al0.4cocrfeni Prepared by Laser-Powder Bed Fusion Using Al and Fecocrni Powders

SSRN

引用

SSRN 2023年

作者： Zhu, Xiangjian Liu, Shan Wang, Xiebin Wang, Guangchun Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials Ministry of Education Shandong University Shandong Jinan250061 China Hebei Key Laboratory of Material Near-net Forming Technology Hebei University of Science and Technology Hebei Shijiazhuang050000 China

In this work, due to the insufficient diffusion of the phase forming element, which promotes the formation of the second phase, a dual phase Al0.4CoCrFeNi high entropy alloy (HEA) with BCC phase content of c.a. 13% and excellent mechanical properties was prepared by laser powder bed fusion (L-PBF) using AlSi10Mg and FeCoCrNi mixing powders. The effect of aging treatment, both with and without preceding solution treatment, on the microstructure and mechanical properties is addressed. Under direct aging, a large amount of nano σ and FCC phase are formed within the BCC phase, spherical L12 phase and dislocation cellular substructure coexist inside FCC grains. However, under solution-aging, the BCC phase is separated by newly generated FCC phase, and showing a sieve-like shape with the σ phase embedded into the phase boundary, the L12 phase is precipitated in a wave-like shape inside FCC grains without existence of dislocation. As a result, direct aging can improve rapidly the strength of the as-built alloy, but the plasticity decreases largely. On the contrary, solution-aging improves the strength while retaining considerable plasticity. Specifically, solution-aging treatment 1200℃/1 h+650℃/50 h simultaneously improves the strength and plasticity of the as-built alloy. And better yet, solution-aging sample 1200℃/1 h+650℃/100 h achieves a synergistic increase in strength and plasticity compared with all the direct aging samples. This work provides a new idea for the preparation of heterogeneous alloys with high second phase content with the low content of phase forming elements, and also provides guidance for the post-treatment performance regulation of dual phase HEAs. © 2023, The Authors. All rights reserved.

关键词： High-entropy alloys

来源：评论

学校读者我要写书评

暂无评论

Damping performance of SiC nanoparticles reinforced magnesium matrix composites processed by cyclic extrusion and compression

引用

Journal of Magnesium and Alloys 2023年第5期11卷 1608-1617页

作者： Mahmoud Ebrahimi Li Zhang Qudong Wang Hao Zhou Wenzhen Li National Engineering Research Center of Light Alloy Net Forming and Key State Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240PR China School of Mechanical Engineering North University of ChinaTaiyuan 030051PR China Nano and Heterogeneous Materials Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094PR China School of Materials Science and Engineering Tsinghua UniversityBeijing 10084PR China

This work dealt with the damping performance and its underlying mechanism in SiC nanoparticles reinforced AZ91D composite(SiC_(np)/AZ91D)processed by cyclic extrusion and compression(CEC).It was found that the CEC process significantly affects the damping performance of the composite due to alterations in the density of dislocations and grain boundaries in the matrix *** there would be dynamic precipitation of the Mg17Al12 phase during processing which increases the phase interface and limits the mobility of dislocations and grain *** results also showed that the damping capacity of 1%SiC_(np)/AZ91D composite continuously decreases with adding CEC pass number and it consistently increases with rising the applied *** the first derivative of the tanδ-T curve,the dominant damping mechanism based on test temperature can be divided into three *** three regions are as follows(i)dislocation vibration of the weak pinning points(≤T_(cr)),(ii)dislocation vibration of the strong pinning points(T_(cr)∼T_(V)),and(iii)grain boundary/interface sliding(≥T_(V))

关键词： Metal matrix composite SiC nanoparticles Severe plastic deformation Temperature-dependent damping curves Damping mechanism

来源：评论

学校读者我要写书评

暂无评论

Effect of cooling temperature on the microstructure and corrosion behavior of X80 pipeline steel

引用

International Journal of Minerals,Metallurgy and materials 2020年第3期27卷 347-353页

作者： Jing Ma Fan Feng Bai-qing Yu Hai-feng Chen Li-feng Fan School of Materials Hebei University of Science and TechnologyShijiazhuang 050018China Hebei Key Laboratory of Material Near-Net Forming Technology Shijiazhuang 050018China School of Transportation Inner Mongolia UniversityHohhot 010070China

Dual-phase accelerated cooling(DPAC) was applied to X80 pipeline steel to obtain its microstructure with different amounts of bainite and ferrite. The microstructure, hardness, and polarization behaviors of the steel, cooled to different temperatures, were investigated. Results showed that, with decreasing cooling temperature, the amount of polygon ferrite(PF) increased while that of acicular ferrite(AF) decreased. The amount of bainite correspondingly decreased, except when cooled to 760°C. Moreover, the grain size of ferrite increased. The corrosion behaviors of different phases were distinct. Martensite/austenite(M/A) islands presented at the grain boundary of the PF phase caused small pits. Numerous micro-corrosion cells were formed in the AF and bainite phases, where micropores were prone to form. X80 pipeline steel cooled to 700°C had the best corrosion resistance in the simulated seawater. The decreased amount of the PF phase reduced the area of cathode, resulting in slight corrosion. About 40 vol% of the bainite phase provided strength while the PF phase provided adequate ductility to the X80 steel. It was concluded that the appropriate cooling temperature was 700°C for ideal corrosion resistance and mechanical properties.

关键词： X80 pipeline steel Dual-phase accelerated cooling microstructure corrosion behavior

来源：评论

学校读者我要写书评

暂无评论

Tailoring microstructure and texture of Mg-3Al-1Zn alloy sheets through curve extrusion process for achieving low planar anisotropy

引用

Journal of materials Science & technology 2022年第18期113卷 48-60页

作者： Jun Xu Bin Jiang Yuehua Kang Jun Zhao Weiwen Zhang Kaihong Zheng Fusheng Pan Institute of New Materials Guangdong Academy of SciencesGuangzhou 510650China National Engineering Research Centre of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou510641China State Key Laboratory of Mechanical Transmissions College of Materials Science and EngineeringChongqing UniversityChongqing 400044China School of Mechanical and Electrical Engineering Hunan City UniversityYiyang413002China

Curve extrusion processes,including symmetric curve extrusion(SCE)and asymmetric curve extrusion(ACE)processes,were proposed to fabricate Mg-3Al-1Zn(AZ31)alloy sheets with the aim of improving planar *** comparison,traditional extrusion(TE)was conducted on producing AZ31 *** dynamic recrystallization and flow behavior of AZ31 Mg alloy during extrusion were examined and analyzed,and the final microstructures and mechanical properties of AZ31 sheets were *** comparison with the TE sheet,finer grain size,more uniform microstructure and weaker tilted basal tex-ture were achieved in the SCE and ACE *** the SCE and ACE sheets exhibited unique textures which basal poles tilted to extrusion direction(ED)and new transverse direction(TD)-tilted texture com-ponent was *** reasons were mainly ascribed to the introduction of additional flow velocity difference along TD during ***,the ACE sheet exhibited the lowest basal pole inten-sity,which was attributed to the introduction of extra asymmetric shear deformation during extrusion *** a result,the ACE sheet showed the lowest yield strength and r-value,but highest elongation and *** the planar anisotropy of AZ31 sheet was achieved by the ACE process.

关键词： Magnesium alloy Curve extrusion Texture Mechanical properties

来源：评论

学校读者我要写书评

暂无评论

Effect of brazing temperature on microstructure and tensile strength ofγ-TiAl joint vacuum brazed with micro-nano Ti−Cu−Ni−Nb−Al−Hf filler

引用

Transactions of Nonferrous Metals Society of China 2024年第8期34卷 2563-2574页

作者： Li LI Yu-tong CHEN Lei-xin YUAN Fen LUO Zhi-xue FENG Xiao-qiang LI School of Materials Science and Engineering East China Jiaotong UniversityNanchang 330013China State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure East China Jiaotong UniversityNanchang 330013China National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China

A novel micro-nano Ti−10Cu−10Ni−8Al−8Nb−4Zr−1.5Hf filler was used to vacuum braze Ti−47Al−2Nb−2Cr−0.15B alloy at 1160−1220℃ for 30 *** interfacial microstructure and formation mechanism of TiAl joints and the relationships among brazing temperature,interfacial microstructure and joint strength were emphatically *** show that the TiAl joints brazed at 1160 and 1180℃ possess three interfacial layers and mainly consist of α_(2)-Ti_(3)Al,τ_(3)-Al_(3)NiTi_(2) and Ti_(2)Ni,but the brazing seams are no longer layered and Ti_(2)Ni is completely replaced by the uniformly distributed τ_(3)-Al_(3)NiTi_(2) at 1200 and 1220℃ due to the destruction of α_(2)-Ti_(3)Al barrier *** transformation at 1200℃ obviously improves the tensile strength of the joint and obtains a maximum of 343 ***,the outward diffusion of Al atoms from the dissolution of TiAl substrate dominates the microstructure evolution and tensile strength of the TiAl joint at different brazing temperatures.

关键词： γ-TiAl alloy micro-nano filler vacuum brazing interfacial microstructure tensile strength

来源：评论

学校读者我要写书评

暂无评论

Shear-accelerated crystallization of glass-forming metallic liquids in high-pressure die casting

引用

Journal of materials Science & technology 2022年第22期117卷 146-157页

作者： L.H.Liu W.J.Gao X.S.Huang T.Zhang Z.Y.Liu C.Yang W.W.Zhang W.R.Li L.Li P.J.Li National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China Department of Mechanical Engineering Tsinghua UniversityBeijing100084China Institute of Eontech New Materials Co. Ltd.Dongguan523662China Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060China

As one of the most important forming technologies for industrial bulk metallic glass (BMG) parts withcomplex shapes, high-pressure die casting (HPDC) can fill a die cavity with a glass-forming metallic liquidin milliseconds. However, to our knowledge, the correlation between flow and crystallization behavior inthe HPDC process has never been established. In this study, we report on the solidification behavior ofZr_(55)Cu_(30)Ni_(5)Al_(10) glass forming liquid under various flow rates. Surprisingly, the resulting alloys display adecreasing content of amorphous phase with increase of flow rate, i.e. increase of cooling rate, suggestingthat crystallization kinetics of glass-forming metallic liquids in the HPDC process is strongly dependenton the flow field. Analysis reveals that the accelerated crystallization behavior is mainly ascribed to therapid increase in viscosity with a decreasing temperature as well as to the huge shear effect in the glassforming liquid at the end stage of the filling process when the temperature is close to the glass-transitionpoint;this results in a transition from diffusion- to advection-dominated transport. The current investigation suggests that flow-related crystallization must be considered to assess the intrinsic glass-formingability of BMGs produced via HPDC. The obtained results will not only improve the understanding ofcrystallization dynamics but also promote the high-quality production and large-scale application of BMGparts.

关键词： Crystallization Shear Supercooled liquid High pressure die casting

来源：评论

学校读者我要写书评

暂无评论

Tuning dual three-dimensional porous copper/graphite composite to achieve diversified utilization of copper current collector for lithium storage

引用

Rare Metals 2021年第10期40卷 2802-2809页

作者： Xia Ma Zhi-Jia Zhang Jia-Min Wang Shi-Hao Sun Shao-Fei Zhang Shen Yuan Zhi-Jun Qiao Zhen-Yang Yu Jian-Li Kang Wei-Jie Li State Key Laboratory of Separation Membrane and Membrane Processes Tianjin Municipal Key Laboratory of Advanced Fibers and Energy StorageSchool of Materials Science and EngineeringSchool of Mechanical EngineeringTiangong UniversityTianjin 300387China School of Materials Science and Engineering Tianjin UniversityTianjin 300072China School of Materials Science and Engineering Hebei Key Laboratory of Material Near-Net Forming TechnologyHebei University of Science&TechnologyShijiazhuang 050018China Institute for Superconducting and Electronic Materials University of WollongongWollongongNSW 2522Australia

Graphite anode materials are widely used in commercial lithium-ion batteries;however, the long electron/ion transportation path restricted its high energy storage. In this experiment, we designed a copper/graphite composite with a dual three-dimensional(3 D) continuous porous structure combining used nonsolvent-induced phase separation and heat treatment, in which a large amount of graphite is embedded in the 3 D porous copper/carbon architecture. In the novel structure, not only the electron and Li^(+) transmission performances are improved, but also the space of current collector is fully utilized. Meanwhile,carbonized polyacrylonitrile network stabilizes the interface between graphite and copper matrix. The obtained copper/graphite composite anode has an initial discharge capacity of 524.6 mAh·g^(-1), a holding capacity of350 mAh·g^(-1) and excellent cycle stability(299.3 mAh·g^(-1) after 180 cycles at 0.1 C rate), exhibiting good electrochemical performance. The experimental results show that the mass loading of the copper/graphite composite electrode material is about 4.39 mg·cm^(-2). We also envisage replacing graphite with other high-capacity active materials to fill the current collector, which can provide a reference for the future development of next-generation advanced electrodes.

关键词： Graphite anode Copper current collector Dual three-dimensional porous Nonsolvent-induced phase separation Heat treatment

来源：评论

学校读者我要写书评

暂无评论

High-temperature friction and wear properties of valve-seat pair with different ni contents 5

High-temperature friction and wear properties of valve-seat ...

引用

2024 5th International Conference on Advanced materials and Intelligent Manufacturing, ICAMIM 2024

作者： Zeng, Xiaoxiao Luo, Changzeng Li, Zhijie Wang, Huajie Qu, Shengguan Duan, Chenfeng Weichai Power Co. Ltd. Weifang261061 China State Key Laboratory of Engine and Powertrain System Weifang261061 China National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of Technology Guangzhou510640 China School of Automotive Studies Tongji University Shanghai201804 China College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing211106 China

A detailed study is conducted on the high-temperature wear performance of valve seat rings with different Ni contents. The wear resistance of two types of contact pairs is studied through methods such as three-dimensional profile, wear amount, and wear morphology. Research has shown that the friction coefficients of both contact pairs gradually decrease with increasing temperature, while the wear amount of both contact pairs shows a trend of first decreasing and then increasing, and both have the lowest wear amount under 500℃ conditions. The wear performance of Inconel 751 material contact pairs is better at room temperature, but Pyromet 31 material contact pairs have stronger stability under high-temperature conditions. Therefore, Pyromet 31 material has better wear and wear resistance in high-temperature environments. Temperature can affect the hardness of materials, resulting in varying degrees of material softening, and also affect the formation rate of oxide films on wear surfaces. The rapid formation of oxide films is an important reason for the greater wear resistance of Pyromet 31 materials. 2025 Published under licence by IOP Publishing Ltd.

关键词： Oxide films

来源：评论

学校读者我要写书评

暂无评论

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

请选择保存的检索档案：

请选择收藏分类：

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

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

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：