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STUDIES ON PRIMARY CRYSTALLIZATION OF RAPIDLY QUENCHED Al-Ni-Cu-Nd METALLIC GLASS BY USING HIGH RESOLUTION TRASMISSION ELECTRON MICROSCOPY

Y.D.Xiao , W.X.Li , D.Jacovkis , M.T.Clavaguera-Mora , J.Rodriguez-Viejo , N.Clavaguera

金属学报(英文版)

Rapidly solidified Al87Ni7Cu3Nd3 metallic glasses, prepared by using melt spinning, were treated under both isothermal and non-isothermal regime. The amorphous rib-bon and the annealed samples were closely examined by means of differential scan-ning calorimetric, conventional X-ray diffraction and high resolution transmission electron microscopy with selected-area electron diffraction, with special interest in pri-mary crystallization into α-Al nanocrystalline particles, in order to understand struc-tural characteristics of Al-based amorphous/nanocrystalline alloys, and nucleation and grain growth mechanism on the nanometer scale during primary crystallization. The results show that, the as-prepared ribbons are fully amorphous and homogeneous in the micron scale, but contain high density of quenched-in clusters or crystallite embryos. Primary crystallization mainly leads to formation of two-phase mixture of α-Al crystal and residual amorphous phase. The annealed ribbons exposed isother-mally at 110℃ for 5, 130 minutes and heated continuously up to less than 310℃ at 40℃/min consist of large amount of α-Al fec crystal nanoparticles dispersed uni-formly in an amorphous matrix. However, a very little amount of finer orthorhombic Al3Ni intermetalics particles exist in the annealed ribbons heated up to 310℃. During primary crystallization, the leading kinetic mechanics to impede growth of the α-Al crustal is soft impinaement, instead of geometric impinqement.

关键词: rapid solidification , null , null

Y3+,W6+掺杂的矿物锂快离子导体Li1.2+x-yYxTi1.9-xAl0.1Si0.1WyP2.9-yO12系统的合成与表征

张玉荣 , 陈宇

中国稀土学报

以LiTi2(PO4)3为母体,以天然高岭石为起始原料,经高温固相反应制得了一系列新的锂快离子导体Li1.2+x-yYxTi1.9-xAl0.1Si0.1WyP2.9-yO12(以下简称Y-W-Lisicon).X射线粉末衍射分析结果表明,在x=0.10,y≤0.20及x=0.20,y≤0.20的组成范围内能得到空间群为R3c,类似于Nasicon的三方结构,但在上述组成范围内均有杂相存在.应用交流阻抗技术测定电导率的结果表明,起始组成为x=0.10,y=0.10的样品在室温下具有较高的离子电导率,为1.65×10-5 S·cm-1;组成为x=0.20,y=0.10的样品在573 K时具有较高的离子电导率,为6.53×10-3 S·cm-1,该样品的分解电压为3.0 V.

关键词: 矿物锂快离子导体 , Y-W-Lisicon , 高岭石 , 稀土

Thermal transport properties and electronic structure of W-doped rubidium blue bronzes Rb(0.3)Mo(1-x)W(x)O(3) (x=0, 0.001, 0.003, 0.005)

Physica B-Condensed Matter

The thermoelectric power (TEP), electrical resistivity and X-ray photoemission spectrum (XPS) of the W-doped rubidium blue bronzes Rb(0.3)Mo(1-x)W(x)O(3) (x=0, 0.001, 0.003, 0.005) were investigated. It is shown that the Peierls transition is suppressed with the increase in the concentrations of the doped W ions. The sign change of the TEP was observed for all the samples. At low temperature below the Peierls transition, the W-doping makes the obvious decrease in the absolute values of TEP, especially for Rb(0.3)Mo(1-x)W(x)O(3) (x=0.003, 0.005). Furthermore, as compared with the pure blue bronzes, the enlarged difference between Peierls transition temperature (T(p)) and the sign changed temperature (T(s)) in Rb(0.3)Mo(0.999)W(0.001)O(3) bronzes was observed and discussed in detail. (C) 2010 Elsevier B.V. All rights reserved.

关键词: Charge density wave;Blue bronze;Thermoelectric power;Resistivity;charge-density-wave;thermoelectric-power;oxide bronzes;k0.3moo3;transition;scattering;rb0.3moo3;state;impurities;k0.30moo3

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

X射线荧光测定复式碳化物中W、Ti、Ta、Fe方法研究

颜晓华 , 彭宇 , 苏明

硬质合金 doi:10.3969/j.issn.1003-7292.2015.04.008

复式碳化物是一种硬质合金行业和其他新材料行业广泛使用的原料,常用的复式碳化物由TiC、WC、TaC等固溶生成.本方法以m(Li2B4O7)∶m(LiBO2)=67∶33为熔剂制备复式碳化物的熔融玻璃片,采用Bruker公司的S8 Tiger型顺序式X射线荧光光谱仪和Spectra plus基体效应校正等软件,在熔融条件、标样的设置、转换系数的计算、仪器条件等方面进行探讨,建立了X射线荧光光谱仪测定复式碳化物中W、Ti、Ta、Fe的含量方法,方法分析测定范围(氧化物)W 25.55%~52.41%、Ti 8.89%~31.48%、Ta 15.03%~28.54%、Fe 0.032%~ 1.07%,结果表明,方法的精密度和准确度较好.

关键词: 复式碳化物固溶体 , 化学分析 , X射线荧光光谱 , W , Ti , Ta , Fe

Amorphous forming ability of Co-X(X=Cr, Mo, W)  magnetic thin films

Gaowu QIN

金属学报(英文版) doi:10.1016/S1006-7191(08)60117-9

Co-X(X=Cr, Mo, W) magnetic thin films were prepared by using DC magnetron sputtering, and their structures were examined by using X-ray diffraction (XRD). The amorphous forming ability (AFA) of the three alloy systems was discussed based on thermodynamic calculation and experiments. The results show that the Co-Mo thin films exhibit the largest AFA among them, and the Co-W thin films are condition-dependent amorphous while the Co-Cr thin films are hard to be amorphous, which is consistent with the thermodynamic calculation. The difference in AFA for the alloys of these three systems is finally ascribed to three main factors: differences in electronegativity, electron density and atomic size between Co and X elements.

关键词: Amorphous forming ability , Co-Cr , Co-Mo , Co-W

Li1+2x+yAlxNdyTi2-x-ySixP3-xO12系统的锂快离子导体研究

陈瑞福 , 王文继

无机材料学报

Li1+2x+yAlxNdyTi2-x-ySixP3-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,x0.3和y=1.0,x0.4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

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