X.G
,
Yang
,
Q.A. Zhang
,
K. Y Shu
,
YL. Du
,
YQ. Lei and Q.D. Wang (Department of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China )W.K. Zhang(Department of Applied Chemistry
,
Zhejiang University of Technology
,
Hangzhou 3100l4
,
China )G.L. Lu(Central Lab
,
Zhejiang University
,
Hangzhou 310028
,
China)
金属学报(英文版)
The annealing treatment was found to improve the cyclic stability but to degmde discharpe capacity, activation and high-rate discharpeability for the Ti-substituted AB2type alloy electrode. A larper polarization was found in the annealed alloy because of its poor discharpe kinetics resulted hem the structural homogeneity. At larae discharpe cumnts, the hydmpen dchsion in the bulk of the alloy was mpaofed as the mte-determining step. Based on the P ressure-composition isotherm measurement, we concluded that the decrease in discharpeability of the annealed alloy is owing to the low and flat pressure plateau, as well as the large hysteresis, but the hydrgen stomge density almost remains unchangeable after annealing.
关键词:
AB_2
,
null
,
null
,
null
,
null
,
null
J.L. Li
,
K.F. Wang
,
J. Li
,
Z.M. Yao and W. Ke(Fushun Petroleum Institute
,
Fushun 113001
,
China)(Department of Chemical Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)(Institute of Corrosion and Protection of Metals
,
The Chinese Academy of Sciences
,
Shengyang 110015
,
China)
金属学报(英文版)
Influence of hydrogen attack on mechanical and fatigue properties of 1020, 15CrMo and 2.25Cr-1Mo steels has been studied, which were exposed to gaseous hydrogen at pressure of 18MPa and 300-480℃ for up to 480h. The results of fatigue test showed that hydrogen attack (HA) resulted in an obvious change in fatigue properties of 1020 and 15CrMo steels, however, 2.25Cr-1Mo steel showed a lower susceptibility to hydrogen attack due to the addition of Cr and Mo. Fatigue crack behaviour for 1020 steel is attributed to hydrogen attack damage and the crack closure induced by the rough cracking surface, which lead to a valley on △Kth～HA% plot. The change in the fatigue behaviour of 15CrMo steel is possibly caused by severe surface decarburization.
关键词:
hydrogen attack
,
null
,
null
,
null
X.G. Yang
,
K. Y. Shu
,
X.B. Zhang
,
Y.Q. Lei and Q.D. Wang(Department of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)W. K. Zhang(College of Applied Chemistry
,
Zhejiang University of Technology
,
Hangzhou 310014
,
China)G.L. Lu(Centre of Analysis and Mesurement
,
Hangzhou University
,
Hangzhou 310028
,
China)
金属学报(英文版)
The effect of La alloying on the crystalline characteristics, electrochemical capacity and activity of AB2 type Zr-Cr-Ni hydride electrodes was investigated. It was found that La alloying was able to shorten the activating process from 15 cycles of La-free alloy to 2 cycles, and that the main phase shifts from C14 to C15 by XRD analysis. It may be attributed to the modification of surface chemical states and change in internal microstructures. However, the cycling stability was also found to degrade severely for La-containing hydride electrode because of the collapse of its distorted lattice.
关键词:
Zr-Cr-Ni hydrogen storage alloy
,
null
,
null
Yanqi WANG and Xijun WU(Dept. of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)Linhua YE
,
Limin TONG and Yonghang SHEN(Dept. of Physics
,
Zhejiang University
,
Hangzhou 310027
,
China)
材料科学技术（英文）
ZrO2, CuO, Al2O3 and SiO2 mixed nanopowder was used to coat the head of sapphire single crystal fiber for improving the properties of high-temperature single crystal fiber sensor. The result indicates that the head coated with above mixed nanopowder shows better optical stability,shorter response time and higher thermal shock resistance, in comparison with the head coated with coarse-grained particles with the same chemical compositions
关键词:
Tao ZHU
,
Gaorong HAN
,
Gaoling ZHAO and Zishang DING(Dept. of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)( State Key Lab. of Magnetism
,
Institute of Physics
,
Chinese Academy of Sciences
,
P.O.Box 603
,
Beijing 100080
,
China)
材料科学技术（英文）
Raman spectra of the PbTiO3 films via sol-gel process were investigated by using a Jobin Yvon U1000 system. Compared with the Raman spectra of the PbTiO3 single crystals, Raman peaks of PbTiOs films shift downward, which is attributed to the stress effect in the PbTiO3 films exerted by the substrate and the size effect on the Raman frequencies
关键词:
Xiuchun YANG(Dept. of Physical Chemistry
,
University of Science and Technology Beijing
,
Beijing 100083
,
China)Gaorong HAN
,
Xiabin ZHANG
,
Piyi DU and Zishang DING(Dept. of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)Ze ZHA
材料科学技术（英文）
Photoluminescence of nanometer SiC powder was found firstly. By TEM, SAED, FTIR and chemical analyses, it is suggested that the quantum confinement effect of nanometer β-SiC be responsible for the blue light and violet emission
关键词:
Xisheng YE
,
Jian SHA and Zhengkuan JIAO(Dept. of Physics
,
Zhejiang University
,
Hangzhou 310027. China)Zifei PENG and Lide ZHANG(Institute of Solid State Physics
,
Chinese Academy of Sciences
,
Hefei 230031
,
China)
材料科学技术（英文）
Using DTA (difFerential thermal analysis) measurement on nanostructured TiO2, we find two endothermic peaks on the DTA curve. From XRD (X-ray diffraction) analysis of the original nanostructured TiO2 and its heat-treated samples, we obtain the following results: the first endothermic peak corresponds to the desorption of physical or chemical absorption, the second one is related to the structural phase transition from brookite to anatase then to rutile, and this structural phase transition is beneficial to the grain growth of nanocrystal
关键词:
L.Meng
,
T.P.Tu
,
Y.Z.Yang
,
M.S.Liu(Department of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)
金属学报(英文版)
The effects of the impurities Fe, Si, Na, K and a rare earth addition, Ce, on the intrinsic and extrinsic toughening levels have been investigated for the Al-Li based alloys 2090 and 1420. 29K reduction in the toughening level for the alloy 2090 with impurities 0.42% Fe+Si or 0.0132% Na+K i4 identified to be caused by the impurities.An improvement on the fracture toughness can be made by adding 0.05%-0.25% Ce to the alloy 2090. The reason behind this is that Ce microalloying can not only enhance both the intrinsic toughening level and the extrinsic toughening level but also suppress the embrittling behavior of the impurities. However, 0.06%-0.15% Ce microalloying fails to bring about any beneficial effect to the toughening level for the alloy 1420.
关键词:
Al-Li based alloy
,
null
,
null
,
null
Y.L. Chen(Department of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)
金属学报(英文版)
Internal friction measurements on binary and ternary α-phase alloys of Pd with hydrogen and boron have been performed with a torsion pendulum and by observing the cttenuation of ultrasonic pulses. A pronounced damping maximum of binary Pd-B alloys at 220K and measuring frequencies of about 4Hz could not be established at a frequency of 15MH. Ternary Pd-B-H alloys show an additional damping maximum besides the hydrogen Zener effect, which is interpreted in terms of a changed jump frequency of hydrogen in the neighborhood of boron atoms.
关键词:
Pd-B-H alioy
,
null
,
null
,
null
YL. Chen(Department of Materials Science and Engineering
,
Zhejiang University
,
Hangzhou 310027
,
China)
金属学报(英文版)
Some thermodynamic parnmeters of Pd-In alloys with 2 to 70 at. H indium have been determined in the temperuture range 800 to 1000℃ from e.m.f measurements ongalvanic cells with an onsen-cotzducting solid electrolyte. Heats of tnising calculated hem the activities are in excellent agreement with calorimetric data. The relative partial excess hee enengy of indiurn assumes unnsually larpe negative values ap to-174kJ/mol for Pd-rich alloys. Two efficts are discussed to account for the non-idealproperties: The rise Of Fermi enerpy as the valence electron8 of indium enter the 4dand 5sP bands of the alloy and the lattice distortion brought about by the differentmolar volumes of the cofnponents. The rise of the Fermi enerpy, as determlned fromthe activity data, indicates a strict adherence of the alloys to the rigid band model.
关键词:
galvanic cell
,
null
,
null
,
null
,
null
