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Preparation of TiC/Ni_3al Composites by Upward Melt Infiltration

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Journal of Materials Science & Technology 2000年第4期16卷 387-392页

作者： Yi PAN (Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China) Kewei SUN (National Engineering Research Center of Solid Waste Resources Recovery, Kunming University of Science and Technology,Kunming 650093, China) Department of Materials Science and Engineering Zhejiang University Hangzhou 310027 China National Engineering Research Center of Solid Waste Resources Recovery Kunming University of Science and Technology Kunming 650093 China

TiC/Ni_3al composites have been prepared using upward infiltration method. The densification was performed by both Ni_3al melt filling and TiC sintering during the infiltration. The dissolution of TiC in liquid Ni_3al has been evidenced by finding Ni_3(al,Ti)C after fast cooling in the TiC/Ni_3al composites. The dissolution may be responsible for the infiltration and sintering. Compared with downward infiltration, the upward infiltration brought about higher strength and fracture toughness and shorter infiltration time. TiC/20 vol. pct Ni_3al composite processed by upward infiltration had a flexural strength of 1476 MPa with a statistic Weibull modulus of 20.2 and a fracture toughness of 20.4 MPa . Better mechanical properties may be attributed to melt unidirectional movement in upward infiltration.

关键词： TiC Preparation of TiC/Ni3al Composites by Upward Melt Infiltration Ni al

EFFECTS OF SMalL ADDITIONS OF Mg AND Ag ON PRECIPITATION PROCESS OF al-Cu-Li-(Mg)-(Ag)-Zr alLOYS

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中国有色金属学会会刊：英文版 1998年第3期8卷 2-7页

作者： Ziqiao, Zheng Biping, Huang Central South Univ of Technology Changsha China

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关键词： al Li alloys microstructure precipitation silver magnesium

Deformation-induced α_2/γ Interfaces in a Hot-deformed Ti-45al-10Nb alloy

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Journal of Materials Science & Technology 1998年第2期14卷 132-138页

作者： Jinguo WANG Lichun ZHANG and Guoliang CHEN (State Key Lab. for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China )Henqiang YE(Lab. of Atomic Imaging of Solids, Institute of Metal Research, Chinese Academy State Key Lab. for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China Lab. of Atomic Imaging of Solids Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The structure change of α2/γ interface in a Ti-45al-10Nb alloy induced by hot deformation was investigated by conventional and high-resolution transmission eIectron microscopy. Two types of hot deformation induced special α2/γ intedeces, coherent intedeces with high density of ledges and semi-coherent α2/γ intedeces were found to be due to the absorption of mobile dislocations into the α2/γ inteface. For the misoriented semi-coherent α2/γ interfaces, the densities of dislocation ledges increase with the misoriented angle between (111)γ and (0001)α2 planes, and 1/3[111] Frank partial dislocations were involved in the dislocation ledges. Formation mechanism of these deformation-induced α2/γ interfaces was discussed to be related to the role of α2/γ interface5 adjusting the deformation as a dislocation sink absorbing the slipping dislocations in the γ phase

关键词： al Ti Interfaces in a Hot-deformed Ti-45al-10Nb alloy Deformation-induced

Static and Dynamic Precipitation Behavior of the al-20wt.% Zn alloy

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Chinese Physics Letters 2016年第5期33卷 63-66页

作者：刘崇宇江鸿杰王春霞亓海全李义兵马明臻刘日平 Key Laboratory of New Processing Technology for Nonferrous Metal & Materials(Ministry of Education) Guilin University of Technology State Key Laboratory of Metastable Materials Science and Technology Yanshan University Guangxi Key Laboratory of Universities for Clean Metallurgy and Comprehensive Utilization of Nonferrous Metal Resources

The static and dynamic precipitation behavior of solution-treated binary al-20 wt.% Zn alloy is investigated via artificial aging, cold rolling and artificial aging combined with cold rolling. The solution-treated al-Zn alloy exhibits high thermal stability during aging, and low densities of nano-sized Zn particles are precipitated along with AI grain boundaries after aging at 200℃ for 13 h. Compared with static precipitation, dynamic precipitation occurs more easily in the al-Zn alloy. Zn clusters are obtained after cold rolling at an equivalent plastic strain of 0.6, and the size of the Zn phase reaches hundreds of nanometers when the strain is increased to 12.1. The results show that the speed of static precipitation can be significantly enhanced after the application of 2.9 rolling strain. Grain refinement and defects induced by cold rolling are considered to promote Zn precipitation. The hardness of al-Zn alloy is also affected by static and dynamic precipitations.

关键词： Zn alloy in on as al Static and Dynamic Precipitation Behavior of the al-20wt of

Optical and Structural Properties of In_(0.52)al_(0.48)As/InP Structures Grown at Very High Arsenic Overpressures by Molecular Beam Epitaxy

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Journal of Materials Science & Technology 1998年第3期14卷 231-235页

作者： S.F. Yoon(School of Electrical and Electronic Engineering, Nanyang Technological University, Nanyang Avenue,Singapore 639798, Rep. of Singapore School of Electrical and Electronic Engineering Nanyang Technological University Singapore 639798 Nanyang Avenue Singapore

Growth of ln0.52al0.48As epitaxial layers on lnP(100) substrates by molecular beam epitaxy at a wide range of arsenic overpressures (V/III flux ratios from 30 to 300) has been carried out. Analysis performed using low-temperature photoluminescence (PL) and double-axis X-ray diffraction (XRD) shows a strong and prominent dependence of the PL and XRD linewidths on the V/III flux ratio. Under our growth conditions, both the PL and XRD linewidths exhibit a minimum point at a V/III flux ratio of 150 which corresponds to a maximum in the PL intensity and XRD intensity ratio. Flux ratios exceeding 150 result in an increase in both the PL and XRD linewidths corresponding to a reduction in their associated intensities. Room temperature Raman scattering measurements show a narrowing in the lnAs-like and alAs-like longitudinal-optic (LO)phonon linewidths which broaden at high flux ratios, while the LO phonon frequencies exhibit a gradual reduction as the flux ratio is increased. PL spectra taken at increasing temperatures show a quenching of the main emission peak followed by the evolution of a broad lower energy emission which is possibly associated with deep lying centres. This effect is more prominent in samples grown at lower V/III flux ratios. Hall effect measurements show a gradual reduction in the mobility in correspondence to an increase in the electron concentration as the flux ratio is increased.

关键词： As/InP Structures Grown at Very High Arsenic Overpressures by Molecular Beam Epitaxy InP Optical and Structural Properties of In al

A New α Ti alloy (Ti-4al-2V) for Marine Engineering

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Journal of Materials Science & Technology 2001年第1期17卷 77-78页

作者： Dong LI NW Inst Nonferrous Met Res Xian 710016 Peoples R China

NIN has developed a new type of Ti alloy. It is suitable for structure pieces applied in hightemperature and high-pressure water/steam conditions. Its nominal composition is Ti-4al-2V. In this paper, its microstructu... 详细信息

关键词： Ti-4al-2V al for Marine Engineering

Three principles for preparing al wire with high strength and high electrical conductivity

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Journal of Materials Science & Technology 2019年第5期35卷 742-751页

作者： J.P.Hou R.Li Q.Wang H.Y.Yu Z.J.Zhang Q.Y.Chen H.Ma X.M.Wu X.W.Li Z.F.Zhang Materials Fatigue and Fracture Division Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China National Quality Supervision & Inspection Center of Electrical Equipment Safety Performance Zhejiang Huadian Equipment Testing Institute Hangzhou 310015 China Electric Power Research Institute of Liaoning Electric Power Co. Ltd. Liaoning Electric Power Co. Ltd. Shenyang 110006 China Department of Materials Physics and Chemistry School of Materials Science and Engineering Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University Shenyang 110819 China

The trade-off relation between the strength and the electrical conductivity has been a Iong-standing dilemma in metallic materials. In the study, three key principles, *** grains, sharp texture and nano-scale precipitates, were presented for preparing al wire with high strength and high electrical conductivity based on the specially designed experiments for breaking the mutually exclusive relation between the strength and the electrical conductivity. The results show that the elongated grains could lead to a higher electrical conductivity in al wire without sacrificing the strength;while, the sharp texture can efficiently strengthen the al wire without influencing the electrical conductivity. Furthermore, nano-scale precipitates with proper size can simultaneously improve the strength and electrical conductivity of al alloy wire. Under the guidance of the above three key principles, al wires with high strength and high conductivity were prepared.

关键词： al wire Texture Precipitates Strength Electrical conductivity

Microstructure Evolution of Rapidly Solidified Ti_3al-2Nb alloy

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Journal of Materials Science & Technology 1996年第2期12卷 100-104页

作者： Rui XU Yuyou CUI Dong LI and Zhuangqi HU (State Key Lab. of RSA, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China)Daming XU and Qingchun LI (Dept. of Materials Science and Technology, Harbin Institute of Technology, Harb HARBIN INST TECHNOL DEPT MAT SCI & TECHNOLHARBIN 150001PEOPLES R CHINA

It has been found from the analysis of X-ray diffraction and the observation of TEM that the metastable ordered orthorhombic martensite phase in the rapidly solidified Ti3al-2Nb alloy transforms to various phases at different aging temperatures. When the alloy aged at temperature of 500℃ for 20 min, the phase decomposition into B2 and O phases is related to the stressin the alloy. When the aged temperature above 600℃, the phase transforms to α2 phase by both shearing and chemical ordering

关键词： al Ti

Evaluation of al and Some of Its alloys as Anode Materials vs γ-MnO_2 as Cathode Material and Ore Produced γ-MnO_2 vs Zn Anode in KOH Solution

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Journal of Materials Science & Technology 2006年第1期22卷 25-30页

作者： A.M.A.Hashem Kh.S.Abou-El-Sherbini S.Zein El Abedin H.Abbas Inorganic Chemistry Department National Research CentreBehoes StreetDokkiCairoEgypt Physical Chemistry Department National Research CentreBehoes StreetDokkiCairoEgypt

In this study electrochemical performance of al and some of its alloys （al-Zn, al-rvlg and al-rvln） anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order al-Zn〉al-Mg〉al〉al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy （SEM）. SEM morphologies of al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while al-Mn morphology shows a needle-like structure. Electrolytic manganese dioxide （EMD） produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore （β-MnO2） by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample （EMD1） was performed well in comparison with EMD standard （EMD2）（commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S）. SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.

关键词： Electrolytic MnO2 Zn al alkaline batteries