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中国有色金属学会会刊：英文版 2007年第2期17卷 301-306页

作者：陈冲刘忠侠任波王明星翁永刚刘志勇 Key Laboratory of Material Physics of Ministry of Education Zhengzhou University

P and re complex modification of hypereutectic Al-Si alloys was conducted. The influences of P, re content on the microstructure and mechanical properties of alloys were investigated. The complex modifications of P and re make the coarse block primary silicon obviously refined and the large needle eutectic silicon modified to the fine fibrous or lamella ones. P mainly refines the primary silicon, but excess P is unfavorable to the refinement of primary silicon. re can well refine the primary and eutectic silicon, but its modification effect on the eutectic silicon is more obvious. P can repress the modification of re on the eutectic silicon. The alloys with the additions of 0.08% P and 0.60% re have the optimal microstructure and the highest mechanical properties. Compared with the unmodified alloy, the primary silicon of alloys can be refined from 66.4 μm to 23.3 μm and the eutectic silicon can be refined from 8.3 μm to 5.2 μm. The tensile strength is improved from 256 MPa to 306 MPa and the elongation is improved from 0.35% to 0.48%.

关键词：过共晶合金 A1-Si合金复合改性 P re 显微结构力学性质

re effects in model Ni-based superalloys investigated with first-principles calculations and atom probe tomography

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Chinese Physics B 2020年第4期29卷 232-241页

作者： Dianwu Wang Chongyu Wang Tao Yu Wenqing Liu Central Iron and Steel research Institute Beijing 100081China Department of Physics Tsinghua UniversityBeijing 100084China Key Laboratory for Microstructures Shanghai UniversityShanghai 200444China

The phase partition and site preference of re atoms in a ternary Ni-Al-re model alloy,including the electronic structure of different re configurations,are investigated with first-principles calculations and atom probe *** re distribution of single,nearest neighbor(NN),next-nearest neighbor(NNN),and cluster configurations are respectively designed in the models withγandγ*** results show that the re atoms tend to enteringγphase and the re atoms prefer to occupy the Al sites inγ*** re cluster with a combination of NN and NNN re-re pair configuration is not preferred than the isolated re atom in the Ni-based superalloys,and the configuration with isolated re atom is more preferred in the ***,the electronic states are analyzed and the energetic parameters are *** electronic structure analyses show there exists strong Ni-re electronic interaction and it is mainly contributed by the d-d *** characteristic features of the electronic states of the re doping effects are also *** is also found that re atoms prefer the Al sites inγside at the *** density of states at or near the Fermi level and the d-d hybridizations of NN Ni-re are found to be important in the systems.

关键词： re distribution first-principles calculations atom probe tomography Ni-based superalloys

Effect of re on the ignition-proof, microstructure and properties of AZ91D magnesium alloy

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Journal of University of Science and Technology Beijing 2005年第6期12卷 540-544页

作者： Zhihong Chen Xueping ren Ya Zhang Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

The magnesium alloy is prone to burn during die-casting, which limits its applications severely, so the effect of adding rare earth （re） on the ignition-proof of AZ91D Mg alloy is studied. The results indicate that the addition of mischmetal re elements has a remarkable influence on the ignition-proof property of the magnesium alloy. It is found that the ignition temperature of the magnesium alloy can be greatly raised by adding a proper amount of re. When the amount is 0.1wt%, the ignition temperature reaches 877℃ which is 206℃ higher than that of AZ91D without re and the mechanical properties of the alloy are also improved, However, the amount of re must be properly controlled because too much re would induce grain coarsening and reduce the mechanical properties.

关键词： AZ91D magnesium alloy ignition-proof re mechanical properties microstructure

MECHANISM　OF　re-B-V　CO-PERMEATION

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中国有色金属学会会刊：英文版 1997年第1期7卷 92-96页

作者： Li, Fengzhen Liu, Zhaojing Jin, Quan Xu, Zhihui Harbin Univ of Science & Technology Harbin China

ＭＥＣＨＡＮＩＳＭＯＦＲｅＢＶＣＯＰＥＲＭＥＡＴＩＯＮ①ＬｉＦｅｎｇｚｈｅｎ，ＬｉｕＺｈａｏｊｉｎｇ，ＪｉｎＱｕａｎ，ＸｕＺｈｉｈｕｉＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅ... 详细信息

ＭＥＣＨＡＮＩＳＭＯＦＲｅＢＶＣＯＰＥＲＭＥＡＴＩＯＮ①ＬｉＦｅｎｇｚｈｅｎ，ＬｉｕＺｈａｏｊｉｎｇ，ＪｉｎＱｕａｎ，ＸｕＺｈｉｈｕｉＤｅｐａｒｔｍｅｎｔｏｆＭａｔｅｒｉａｌｓＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，ＨａｒｂｉｎＵｎｉｖｅｒ...

关键词： re B V co permeation mechanism kinetics rare earth pasty agent

Evolution of TCP Phase During Long Term Thermal Exposure in Several re-Containing Single Crystal Superalloys

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Acta Metallurgica Sinica(English Letters) 2020年第5期33卷 731-740页

作者： Zihao Tan Lin Yang Xinguang Wang Yunling Du Lihua Ye Guichen Hou Yanhong Yang Jinlai Liu Jide Liu Jinguo Li Yizhou Zhou Xiaofeng Sun School of Materials Science and Engineering Shenyang University of Technology111 Shenliao RoadShenyang 110870China Superalloys Division Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China

The application and component designs of single crystal superalloys are restricted by the precipitation of topologically closed packed(TCP)phases,which can deteriorate the microstructural stability of the alloys *** researches concerning the type and morphology evolution of TCP phases under elevated temperature conditions have been reported *** the present work,three re-containing single crystal alloys were designed to investigate TCP phase evolution via long term isothermal exposure tests at 1120℃while the effects of re on the microstructural characteristic and elements segregation were also *** results showed that the addition of re increased the instability of the alloys and the volume fraction of the TCP phases exceeded 5 vol%when the re content reached 3 wt%.The increasing re content had also raised the precipitation temperature of TCP phases but it did not change the type of them after long term aging;all the TCP particles were identified asμphase in this ***,the elements segregation became considerably serious as re addition increased constantly,which brought about various morphologies of theμphase in the experimental *** particular,the rod-like and needle-likeμphases demonstrated the typical orientation withinγmatrix while the blockyμphase was dispersedly distributed in the *** specific orientation relationship could be observed in theμphase when the addition of re exceeded certain threshold value.

关键词： Single crystal superalloys Topologically closed packed(TCP)phase re Elements segregation Morphology

Composition-tuned oxidation levels of Pt-re bimetallic nanoparticles for the etherification of allylic alcohols

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Nano research 2018年第11期11卷 5902-5912页

作者： Yuhao Wang Lindong Li Ke Wu Rui Si Lingdong Sun Chunhua Yan Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China

The catalytic performance of metal nanoparticles is often affected by surface oxidation levels. Instead of post-synthesis oxidation/reduction, we propose an efficient method to modulate the oxidation levels by tuning the composition of bimetallic nanoparticles. Here we report a series of Pt-re bimetallic nanoparticles synthesized via a facile thermal co-reduction process, with a uniform size of approximately 3 nm. The investigation of the growth of the Pt-re nanoparticles suggests that the re atoms were enriched on the surface, as confirmed by X-ray photoelectron spectroscopy. Furthermore, X-ray absorption spectroscopy showed that metallic re was decreased and high-valency reOx species were increased in particles with higher re/Pt ratios. In the etherification of allylic alcohols catalyzed by Pt-re nanoparticles of different compositions under ambient conditions, particles with higher re/Pt ratios exhibited significantly better performances. The highest mass activity of Pt-re bimetallic nanoparticles (127 molg(-1)s(-1)) was more than forty times that of the industrial catalyst CH3reO3 (3 molg(-1)s(-1)). The catalytically active sites were associated with reOx and could be tuned by adjusting the Pt ratio.

关键词： nanocatalysis re Pt oxidation level composition allylic alcohol

SELF-LUBRICATING BEHAVIOR OF Fe-re BINARY ALLOYS

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中国有色金属学会会刊：英文版 1995年第2期5卷 93-97,105页

作者： Xiong, Dangsheng Li, Shizhuo Jiang, Xiaoxia Peterson, M B (Powder Metallurgy research Institute,Central South University of Technology, Changsha 410083 Institute of Metal research, Chinese Academy of Science, Shenyang 110015 Wear Sciences, 925 Mallard C Central South Univ of Technology Changsha China

ＳＥＬＦ－ＬＵＢＲＩＣＡＴＩＮＧＢＥＨＡＶＩＯＲＯＦＦｅ－ＲｅＢＩＮＡＲＹＡＬＬＯＹＳ￥Ｘｉｏｎｇ，Ｄａｎｇｓｈｅｎｇ；Ｌｉ，Ｓｈｉｚｈｕｏ；Ｊｉａｎｇ，Ｘｉａｏｘｉａ；Ｐｅｔｅｒｓｏｎ，ＭＢ（ＰｏｗｄｅｒＭｅｔａｌ... 详细信息

ＳＥＬＦ－ＬＵＢＲＩＣＡＴＩＮＧＢＥＨＡＶＩＯＲＯＦＦｅ－ＲｅＢＩＮＡＲＹＡＬＬＯＹＳ￥Ｘｉｏｎｇ，Ｄａｎｇｓｈｅｎｇ；Ｌｉ，Ｓｈｉｚｈｕｏ；Ｊｉａｎｇ，Ｘｉａｏｘｉａ；Ｐｅｔｅｒｓｏｎ，ＭＢ（ＰｏｗｄｅｒＭｅｔａｌｌｕｒｇｙＲｅｓｅａｒｃｈＩｎｓｔ...

关键词： lubrication re oxide film glaze

CRYSTAL STRUCTUre AND X-RAY POWDER DIFFRACTION DATA FOR re COMPOUND HoNiSb

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中国有色金属学会会刊：英文版 1995年第3期5卷 71-73页

作者： Zeng, Lingmin Li, Jungqin Zhang, Liping Zhuang, Yinghong Hao, Jianmin (Institute of Materials Science, Guangxi University, Nanning 530004)(Tianjin Electronic Materzals research Institute) Guangxi Univ Nanning China

ＣＲＹＳＴＡＬＳＴＲＵＣＴＵＲＥＡＮＤＸ－ＲＡＹＰＯＷＤＥＲＤＩＦＦＲＡＣＴＩＯＮＤＡＴＡＦＯＲＲＥＣＯＭＰＯＵＮＤＨｏＮｉＳｂ￥Ｚｅｎｇ，Ｌｉｎｇｍｉｎ；Ｌｉ，Ｊｕｎｇｑｉｎ；Ｚｈａｎｇ，Ｌｉｐｉｎｇ；Ｚｈｕａｎｇ... 详细信息

ＣＲＹＳＴＡＬＳＴＲＵＣＴＵＲＥＡＮＤＸ－ＲＡＹＰＯＷＤＥＲＤＩＦＦＲＡＣＴＩＯＮＤＡＴＡＦＯＲＲＥＣＯＭＰＯＵＮＤＨｏＮｉＳｂ￥Ｚｅｎｇ，Ｌｉｎｇｍｉｎ；Ｌｉ，Ｊｕｎｇｑｉｎ；Ｚｈａｎｇ，Ｌｉｐｉｎｇ；Ｚｈｕａｎｇ，Ｙｉｎｇｈｏｎｇ；Ｈａｏ，Ｊｉａ...

关键词： re compound HoNiSb X-ray diffraction data crystal structure

The first-principles study on the doping effect of re in Ni3Al

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Progress in Natural Science:Materials International 2008年第7期18卷 861-866页

作者： Song Yu a,*, Chongyu Wanga,b, Tao Yua aCentral Iron and Steel research Institute, Beijing 100081, China bDepartment of Physics, Tsinghua University, Beijing 100084, China Central Iron and Steel research Institute Beijing 100081 China Department of Physics Tsinghua University Beijing 100084 China

Using first-principles density function for molecules method (DMol) and discrete variational method (DVM) based on the density functional theory, we studied the doping effect of re in Ni3Al. The structure relaxation and the alloying energy show that re has a strong Al site preference and leads to the local deformation, which is in agreement with the experimental results and other theoretical results. In addition, the charge density diffierence and the bond order show that re can strongly enhance the interatomic interaction between the nearest neighbor atoms. From the density of states and the Pauli spectrum, we find that resonance states and localized states are induced by doping re, and the doped re atom forms the hybridized bond with the nearest neighbor atoms.

关键词： The first-principles re Ni3Al

Microstructure of electrodeposited re-Ni-W-P-SiC composite coating

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中国有色金属学会会刊：英文版 2000年第1期10卷 50-52页

作者：郭忠诚朱诚意翟大成杨显万 Kunming Univ Sci & Technol Dept Met Kunming 650093 Peoples R China

The components and microstructure of the re Ni W P SiC composite coating were analyzed by means of EPXDS, SEM and XRD. The results showed that the composite coating containing 5%～14%re, 4%～7%SiC, 12%～15%P and 5%～6%W was obtained by use of appropriate bath composition and plating conditions. The as deposited composite coating is amorphous and it becomes mixture when the temperature is raised from 200 ℃ to 400 ℃. However, the composite coating is crystal when the temperature is over 400 ℃. Scanning electron microscopy indicates that the heat treatment temperature has no effect on the surface morphologies of the re Ni W P SiC composite coating. This is to say that the composite coating has a better heat stability of microstructure and high temperature oxidation.

关键词： electrodeposition re Ni W P SiC composite coating microstructure