材料期刊网

Phase Transformation and Deformation Mechanism of Ti_3Al-base Alloy

By WANG Shuncai LI Chunzhi GAO Yang CAO Chunxiao YAN Minggao Institute of Aeronautical Materials , Beijing , 100095 , China.To whom correspondence should be addressed.

材料科学技术（英文）

The phase transformation and deformation mechanism of the alloy based on composition Ti_3Al with addition of Nb,V,Mo have been studied by use of transmission electron microscopy (TEM).It has been shown that the orientation relationship of α_2 phase transformed from β phase is:(0001)α_2// (l10)β,[1210]α_2//[111]β.The present dislocation slip systems in α_2 phase are (1100)[0001] and (1100)<1120>.There also exist α_2 twins which have new twin relationship and the twin plane is (2021).

关键词: Ti_3Al-base alloy , null , null

Institute of Materials Science at Jilin University——A Brief Overview

WANG Yuming Institute of Materials Science , Jilin University , Changchun , 130023 , China

材料科学技术（英文）

关键词:

Image analysis of periodic rain accelerated corrosion of aeronautical aluminium alloys

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

Periodic rain tests have been carried out for simulating atmospheric corrosion of aeronautical aluminium alloys. A digital image preprocessing and analysis method based on wavelet transformation was used to study the corrosion morphology of aluminium alloys samples, through which an image feature parameter 8 was extracted and discussed. The influences of orthogonal experiment parameters on acceleration were analyzed according to image feature parameter 6 with analysis of variance (ANOVA) method, and the optimal parameters for accelerated corrosion test were also obtained. The result was shown to be consistent with that from weight loss method. (c) 2007 Elsevier B.V. All rights reserved.

关键词: aeronautical aluminium alloys;accelerated corrosion;linage analysis;simulated environment;atmospheric corrosion;electrochemical impedance;pitting corrosion;exposure;steel;zinc

Li2O对CaO基钢包渣系脱磷能力影响的热力学研究

王宏明 , 李桂荣

上海金属 doi:10.3969/j.issn.1001-7208.2002.06.003

渣金平衡实验表明Li2O替代CaO基钢包渣系中等量CaO使渣系磷酸盐容量Cp提高.在此基础上进行钢液脱磷的工艺性实验,研究了Li2O含量、渣系碱度及氧化性对渣系脱磷能力的影响,并给出了控制转炉钢液在钢包中回磷及钢包渣脱磷的渣系.

关键词: CaO基渣系 , Li2O脱磷渣 , 脱磷 , 热力学

添加BaO和Li2O对CaO基脱硫精炼渣熔点和粘度的影响

祝贞学 , 戴起勋 , 李桂荣 , 王宏明 , 徐明喜

上海金属 doi:10.3969/j.issn.1001-7208.2005.05.005

以CaO-SiO2(22.4%)-Al2O3(11.6％)-CaF2(10％)精炼渣作为基础渣系, 添加BaO或Li2O,固定(CaO+BaO或Li2O)/SiO2=2.5,研究渣系熔点和粘度等熔体特性的变化.结果显示加入BaO、Li2O可以明显降低渣系的熔点和粘度,有效改善渣钢反应的动力学条件.当(BaO,Li2O)=15wt％时,熔渣的熔点分别为1267℃和1185℃,远低于作对比的基础渣的熔点1326℃,当温度为1475℃时,熔渣粘度分别为0.98Pa·s和0.51 Pa·s,远小于基础渣的粘度1.79Pa·s,使渣系具有良好的流动性,将显著提高炼钢精炼渣的精炼性能.

关键词: CaO基熔渣 , BaO , Li2O , 熔点 , 粘度

Improved hydrogen storage performance of Li-Mg-N-H materials by optimizing composition and adding single-walled carbon nanotubes

International Journal of Hydrogen Energy

A systematic investigation on the hydrogen storage properties of Li-Mg-N-H materials with various compositions was performed. Li-Mg-N-H hydrogen storage materials were prepared by mechanically milling LiNH2/MgH2 mixtures with initial molar ratios ranging from 1.5:1 to 3: 1, followed by de/rehydriding at 200 degrees C. It was found that the hydrogen storage capacity of the system was highly dependent on the initial phase ratio of the LiNH2/MgH2 mixture. An optimum hydrogen capacity of about 5 wt% was achieved in the 2.15:1 LiNH2/MgH2 mixture. Different carbon materials, such as the single-walled carbon nanotubes (SWNTs), multi-walled carbon nanotubes, graphite and activated carbon, were used as additive to improve the hydrogen storage performance. It was found that the dehydriding kinetics of the Li-Mg-N-H material could be markedly improved by adding a small amount of SWNTs, especially in the as-prepared state. (c) 2006 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.

关键词: hydrogen storage;dehydriding kinetics;carbon nanotubes;arc-discharge method;system;microstructure;desorption;absorption;behaviors;property;imides

Optical spectra of Ln(3+)(Nd3+, Sm3+, Dy3+, Ho3+, Er3+)-doped Y3GaO6

Journal of Luminescence

Ln(3+) (Ln = Nd, Sm, Eu, Gd, Dy, Ho, Er)-doped Y3GaO6 compounds were prepared by solid-state reaction, and their optical spectra such as absorption, photoluminescence, excitation and time-resolved spectra have been measured for Ln Nd, Sm, Dy, Ho, Er. X-ray powder diffraction shows that the lattice parameters of the compounds (Y(0.96)Ln(0.04))(3)GaO6 decrease with the decrease of the radii of trivalent Ln(3+) ions, indicating that Ln(3+) ions have substituted for y(3+) ions in the lattice. Optical spectra show that there are obvious absorptions at ultraviolet to visible region. The strong emissions in visible and infra-red region show that Y3GaO6 is a suitable host for rare-earth-doped laser crystal and phosphor materials. (C) 2004 Elsevier B.V. All rights reserved.

关键词: crystal-field;absorption-spectra;luminescence;y3ga5o12;glasses;garnet;y2o3;ions;laf3;tb3

向CaO基熔剂中添加Li2O,Na2O,K2O和BaO对钢水回磷控制效果的影响

郭上型 , 董元篪 , 陈二保 , 张友平 , 李桂荣

钢铁研究学报

在1 853 K温度下,用强碱性氧化物Li2O,Na2 O,K2O和BaO分别替代CaO-SiO2-Fe2O3-MnO2-MgO-P2O5系熔剂中的部分C aO,进行钢水回磷控制实验.结果表明,上述添加剂影响钢水脱磷效果的强弱顺序为:Li 2O＞Na2O＞K2O＞BaO.推荐Li2O作为CaO基实验熔剂的首选添加剂.确定钢水回磷控制用CaO基熔剂的优化组成为:W(CaO+Li2O)/WSiO2=2.5,W Li2O=15 %,W(Fe2O3+MnO2)≥2 %.当W(Fe2O3+MnO2 )=2 %时,采用上述组成的熔剂可获得48.1 %的脱磷率.向CaO基熔剂中添加10 %～30 %的 Li2O后,其磷酸盐容量lgCp为20.32±0.22,比未添加Li2O时CaO基熔剂的最大磷酸盐容量值增加了0.5～1.0个数量级.

关键词: 脱磷 , CaO基熔剂 , 添加剂 , 磷酸盐容量

First-principles study on influence of alloying element substitution on dehydrogenation ability of Li(4) BN(3) H(10) hydrogen storage materials

Acta Physica Sinica

A first-principles plane-wave pseudopotential method based on the density functional theory is used to investigate the dehydrogenation properties and the influence mechanism of Li(4)BN(3)H(10) hydrogen storage materials. The binding energy, the density of states and the Mulliken overlap population are calculated. The results show that the binding energy of crystal has no direct correlation with the dehydrogenation ability of (LiM)(4)BN(3)H(10)(M = Ni, Ti, Al, Mg). The width of band gap and the energy level of impurity are key factors to affect the dehydrogenation properties of (LiM)(4)BN(3)H(10) hydrogen storage materials: the wider the energy gap is, the more strongly the electron is bound to the bond, the more difficulty the bond breaks, and the higher wile the dehydrogenation temperature be. Alloying introduces the impurity energy level in band gap, which leads the Fermi level to enter into the conduction band and the bond to be weakened, thereby resulting in the improvement of the dehydrogenation properties of Li(4)BN(3)H(10). It is found from the charge population analysis that the bond strengths of N-H and B-H are weakened by alloying, which improves the dehydrogenation properties of Li(4)BN(3)H(10).

关键词: hydrogen storage materials;first-principles calculation;element;substitution;dehydrogenation;linh2

添加Li_2O的CaO-B_2O_3-SiO_2系微晶玻璃的性能研究

宁革 , 刘敏 , 周洪庆 , 朱海奎 , 许贵军

硅酸盐通报

以Li_2O为烧结助剂,采用DTA、XRD、SEM等分析手段研究了添加1.0～2.5 wt%Li_2O对CaO-B_2O_3-SiO_2(CBS)系微晶玻璃性能的影响.结果表明:Li_2O降低了CBS系微晶玻璃的玻璃转变温度和析晶温度.未添加Li_2O的试样在930 ℃烧结,而添加Li_2O的试样可以在820 ℃以下烧结,Li_2O显著降低了试样的烧结温度.当Li_2O添加量为1.0wt%时,试样可以在760～820 ℃范围内烧结,800 ℃烧结试样介电常数为5.71,介电损耗为0.0024(测试频率为10 MHz).

关键词: 烧结助剂 , LTCC , CBS系微晶玻璃 , 介电性能