材料期刊网

THE STRUCTURE CHANGE OF γ-TiAl IRRADIATED BY 50keV XENON IONS AT ROOM TEMPERATURE

X.M.Meng , L.L.He , D.X.Li

金属学报(英文版)

The structure change of γ-TiAl intermetallic alloy irradiated by 50keV xenon ionswith a dose of 7.6×1018ions/m2 was studied in a high voltage transmission electronmicroscope at room temperature.Some precipitates appeared in the γ-TiAl grains,which have a hexagonal structure with a=0.283nm and c=0.462nm,and seems to bethe disordered Al2 Ti3 phase.The orientation relationship between the precipitates andmatrix is (0001)P//(111 )γ-TiAl and [21 1 0]P//[011]γ-TiA1.

关键词: γ-TiAl alloy , null , null

大爆炸核合成相关的8Li(d, p)9Li反应截面测量

李志宏 , 柳卫平 , 白希祥 , 郭冰 , 连钢 , 颜胜权 , 王宝祥 , 陆昀 , 曾晟 , 苏俊

原子核物理评论 doi:10.3969/j.issn.1007-4627.2005.01.006

利用8Li次级束测量了质心系能量7.8 MeV 2H(8Li, 9Li)1H反应的角分布, 导出了8Li(d, p)9Li反应的天体物理S因子及9Li→8Li+n虚衰变的渐近归一化系数.

关键词: 8Li(d,p)9Li反应 , 角分布 , 天体物理S因子 , 渐近归一化系数

Mg-x Li-Al 变形镁合金微观组织与拉伸性能

许天才 , 彭晓东 , 张玺 , 陈元芳 , 姜军伟 , 陈洁

功能材料 doi:10.3969/j.issn.1001-9731.2014.07.013

利用光学显微镜(OM)、扫描电子显微镜(SEM)、X 射线衍射仪(XRD)分析了 Li 元素对 Mg-x Li-3Al 合金组织的影响,并用电子万能试验机测试合金的拉伸性能.结果表明,Li 含量的变化可以明显改变合金的相组成.当 m (Li)＜5．7％(质量分数)时合金由单一α-Mg 相组成；Li 含量在5．7％~10．3％(质量分数)之间时,合金为α-Mg＋β-Li 双相；m (Li)＞10．3％(质量分数)时合金为单一β-Li 相.合金的塑性随 Li 含量的升高而增加,铸态 LA113合金的延伸率高达37．36％,但挤压态下合金强度随 Li 含量升高而降低,挤压态 LA53合金具有最佳抗拉强度,达到263．28 MPa.当 Li 含量升高,合金中的第二相粒子会出现 Al12 Mg17转变为 LiMgAl2.

关键词: 镁锂合金 , 铸态 , 挤压态 , 微观组织 , 拉伸性能

Theoretical studies of g factors and defect structures for cubic, tetragonal, and orthorhombic Fe+ Centers in alkali halides MX (M = Li, Na; X = F, Cl)

Communications in Theoretical Physics

The EPR g factors for cubic, tetragonal and orthorhombic Fe+ centers in alkali halides MX (M = Li, Na; X = F, Cl) are calculated from second-order perturbation formulas of g factors based on cluster approach for 3d(7) ions in three symmetries. From calculations, the g factors of these Fe+ centers in MX crystals are reasonably explained and the defect structural data for the tetragonal and orthorhombic Fe+ centers are estimated. The results are discussed.

关键词: crystal;and ligand-field theory;electron paramagnetic resonance;defect structure;atomic screening constants;spin-orbit interaction;superposition model;resonance-spectra;epr parameters;crystal-field;scf functions;ions;co2+

Li_1+2x+yAl_xNd_yTi_2-x-ySi_xP_3-xO₁₂系统的锂快离子导体研究

陈瑞福 , 王文继

无机材料学报

Li_1+2x+yAl_xNd_yTi_2-x-ySi_xP_3-xO₁₂ 锂快离子导体（以下简称Al-Nd-Lisicon）可以用精选的天然高岭石Al₄[Si₄O₁₀]（OH）₈为起始原料，经与Li₂CO₃、TiO₂、NH₄H₂PO₄进行高温（800～1000℃）固相反应约20h而制得.一个空间群属于R3c的固溶体导电相可在y=0．5，x≤0.3和y=1.0，x≤0．4的组成范围内发现.该相具有较好的电导性和较低的活化能．起始组成y=1．0,x=0．3的合成物具有最高的电导率，在400℃时；其电导率达到3．08×10^-2S／cm，离子导电激活能为35．2kJ／mol.

关键词: 矿物快离子导体 , null , null

AN X RAY DIFFRACTION STUDY OF THE AGING TRANSFORMATION IN Al Li Cu Zr ALLOY

Y.H. Wei , L.Q. Hu , L.S. Jian , L. Lu and B.S. Xu College of Materials Science and Engineering , Taiyuan University of Technology , Taiyuan 030024 , China

金属学报(英文版)

Theinitialstageofagingtransformationin Al 2 27% Li 2 68 % Cu 0 11% Zr 0 13% Ceal loy at100℃wasstudied by meansof x ray diffraction.It wasconcludedthatordering of Liatom happens whenthealloyissolution treated andquenched, and beforetheformationofδ’ phasethereexitscontinuous phasetransformation processes, namely ordering ,spinodal de composition and both coexistence. Gunier Preston zone was not found in the aging process ofthestudied alloy.

关键词: Al Li Cu Zr alloy , null , null , null , null

锂快离子导体Li1+2x+2yAlxMgyTi2-x-ySixP3-xO12系统的研究

张玉荣 , 王文继

功能材料

以LiTi2(PO4)3为基以天然高岭石为起始原料,经高温固相反应(～900℃)制得了一系列新的锂快离子导体材料Li1+2x+ 2yAlxMgyTi2-x-ySixP3-xO1 2(以下简称Ti-Mg-Lisicon).系统的合成温度随x和y值的增大而降低.应用交流阻抗技术测定的电导率数据结果表明x=0.1,y=0.1的合成物的室温电导率最好为1.01×10-4S/cm,而400℃时x=0.1,y=0.3的合成物的电导率最大,为2.53×10-2S/cm.XRD分析结果表明在x=0.1,y≤0.8;x=0.2,y≤0.6的组成范围内均能得到空间群为R3c的合成物.

关键词: 锂快离子导体 , Ti-Mg-Lisicon , 高岭石

锂快离子导体Li{1+2x+yAlxYbyTi2-x-ySixP3-xO12系统的研究

张玉荣 , 王文继

无机材料学报 doi:10.3321/j.issn:1000-324X.2001.01.019

以LiTi2(PO4)3为基以天然高岭石为起始原料，经高温固相反应(9501150C)制得了一系列锂快离子导体材料Li1+2x+yAlxYbyTi2-x-ySixP3-xO12(以下简称Al-Yb-Lisicon). 系统的合成温度随x和y值的增大而降低. 应用交流阻抗技术测定的电导率数据结果表明y=0.3，x=0.1的合成物的电导率最好，400C时电导率达2.4510-2S/cm，200400C内的电导激活能为38.3kJ/mol. XRD分析结果表明在y=0.3，x0.4及y=0.5，x0.3的组成范围内均能得到空间群为R3c的合成物.

关键词: 锂快离子导体 , Al-Yb-Lisicon , 高岭石

Effect of the impurity Li(x)Ni(1-x)O on the electrochemical properties of 5 V cathode material LiNi(0.5)Mn(1.5)O(4)

Journal of Alloys and Compounds

The formation of impurity Li(x)Ni(1-x)O when synthesizing spinel LiNi(0.5)Mn(1.5)O(4) using solid state reaction method, and its influence on the electrochemical properties of product LiNi(0.5)Mn(1.5)O(4) were studied. The secondary phase LixNi(1-x)O emerges at high temperature due to oxygen deficiency for LiNi(0.5)Mn(1.5)O(4) and partial reduction of Mn(4+) to Mn(3+) in LiNi(0.5)Mn(1.5)O(4). Annealing process can diminish oxygen deficiency and inhibit impurity Li(x)Ni(1-x)O. The impurity reduces the specific capacity of product, but it does not have obvious negative effect on cycle performance of product. The capacity of LiNi(0.5)Mn(1.5)O(4) that contains Li(x)Ni(1-x)O can deliver about 120 mAhg(-1). (C) 2011 Elsevier B.V. All rights reserved.

关键词: Lithium ion batteries;LiNi(0.5)Mn(1.5)O(4);Impurity Li(x)Ni(1-x)O;Electrochemical properties;lithium batteries;rate capability;spinel;performance

(1-x)BaTiO3-xAg0.9 Li0.1 NbO3系无铅压电陶瓷的相结构和电性能研究

宁海霞 , 吴浪

功能材料 doi:10.3969/j.issn.1001-9731.2016.08.024

采用传统陶瓷工艺制备了(1-x)BaTiO3-xAg0.9 Li0.1 NbO3(BT-xALN,0.005≤x≤0.04)系陶瓷,研究了ALN含量的变化对BT-xALN系陶瓷的显微结构、相结构和电性能的影响.结果表明,ALN的引入使陶瓷的晶粒尺寸有所减小.当x≤0.02时,BT-xALN陶瓷均形成了纯的钙钛矿相,表明ALN与BT形成了固溶体;当x=0.01~0.02时,陶瓷存在四方-伪立方相界.陶瓷的压电常数d33和介电常数εr随x增加均先增大后减小.d33在x=0.0075时达到最大值115 pC/N,εr在x=0.025时达到最大值3880;但剩余极化强度Pr随x增加逐渐降低.此外,掺入ALN后陶瓷的居里温度有所降低.

关键词: BaTiO3 , Ag0.9Li0.1NbO3 , 无铅压电陶瓷 , 相结构 , 压电性能