欢迎登录材料期刊网

材料期刊网

高级检索

  • 论文(37216)
  • 图书()
  • 专利()
  • 新闻()

THE EFFECTS OF PULSE BIAS VOLTAGE AND N2 PARTIAL PRESSURE ON TiAIN FILMS OF ARC ION PLATING (AIP)

M.S. Li

金属学报(英文版)

Owing to the characteristics of arc ion plating(AIP) technique, the structure and com-position of TiAlN films can be tailored by controlling of various parameters such ascompositions of target materials, N2 partial pressure, substrate bias and so on. ln thisstudy, several titanium aluminum nitride films were deposited on 1Cr11Ni2 W2Mo Vsteel for compressor blade of areo-engine under different d.c pulse bias voltage and ni-trogen partial pressure. The effects of substrate pulse bias and nitrogen partial pressureon the deposition rate, droplet formation, microstruture and elemental component ofthe films were investigated.

关键词: TiAlN film , null , null , null

V-M(M=Li,Na,K,Sc,Ag)二元系的相图热力学研究

胡标 , 尹明 , 王庆平 , 闵凡飞 , 杜勇

兵器材料科学与工程

基于文献报道的实验数据,采用相图计算(CALPHAD:CALculation of PHAse Diagrams)方法对V-M(M=Li,Na,K,Sc,Ag)5个二元系进行相图热力学研究.通过热力学优化计算获得了一套描述液相、(V)、(Li)、(Na)、(K)、(αSc)、(βSc)和(Ag)相的热力学参数.V-Li、V-Na和V-K体系中的气相视为由组元V、LiLi2、Na、Na2、K和K2混合的理想气体.与实验相图数据对比表明,获得的热力学参数能够准确地描述实验相平衡数据.

关键词: V-M(M=Li,Na,K,Sc,Ag) , CALPHAD方法 , 相图 , 热力学模型

Li_2S-GeS_2-LiI和Li_2S-GeS_2-LiBr-LiI系统玻璃的电导率

杨如玺

材料研究学报

实验得知0.5Li_2S-0.5GeS_2玻璃的电导率高于0.4Li_2S-0.6GeS_2玻璃的电导率。当在这两种组成的玻璃中分别掺杂LiI 后,则后者的电导率可高于前者。在0.4Li_2S-0.6GeS_2玻璃中同时掺杂LiBr 和LiI 后,其电导率约为掺杂一种同量盐玻璃电导率的两倍。本文用弱电解质理论解释了Li_2S-GeS_2玻璃经掺杂LiBr 和LiI 后电导率变化的原因。

关键词: 解离常数 , activity , ameliorator(modification) , organisator(formation) , transition temperature(transus temperature).

Li1+xV3-yMyO8(M=Mo,P)高温阴极放电性能的研究

曹笃盟 , 李志友 , 周科朝

稀有金属材料与工程

采用固相反应法制备了Li1+xV3-yMyO8(M=Mo,P;0≤y≤0.4),研究了不同Mo和P含量对Li1+xV3O8相的影响,并首次对其进行了高温阴极放电性能的研究.结果表明:Mo和P掺杂量分别为y≤0.2和y<0.2时可获得纯Li1+xV3O8相;Mo掺杂使Li1+xV3O8峰值电压提高0.3 V,比容量提高25%,嵌入的Li+量最高可达x=3.8;P掺杂(y≤0.20)对Li1+xV3O8的峰值电压和比容量影响较小.化学嵌锂实验也证实掺杂后的材料具有更快的Li+嵌入速度.

关键词: Li1+xV3O8 , 热电池 , 掺杂 , 比容量

Studies of the local structural parameters of rhombic V2+-V-M centers in MCl : V2+ (M = Li, Na) crystals from EPR data

Journal of Physics and Chemistry of Solids

In this paper, the high-order perturbation formulae of zero-field splitting D, E and g factors g(x), g(y), and g(z) for d(3) ions in rhombic symmetry are established by using a two spin-orbit (S.O.) parameter model in which the contributions due to both the S.O. coupling of the central d(3) ions and that of the ligands are considered. Based on these formulae, the local structural parameters of the rhombic defect centers V2+-V-M (i.e, the V2+ ion and a host metal ion vacancy V-M) in MCl:V2+ (M = Li, Na) crystals are estimated by calculating their EPR parameters. The results are discussed. (C) 1998 Elsevier Science Ltd. All rights reserved.

关键词: inorganic compounds;crystal fields;defects;electron paramagnetic;resonance (EPR);ions

A flexible nanostructured sulphur-carbon nanotube cathode with high rate performance for Li-S batteries

Energy & Environmental Science

We report the template-directed synthesis of sulphur-carbon nanotubes and their use to form a membrane that is binder-free, highly conductive and flexible. This nanostructured membrane is used as a self-supporting cathode without metal current-collectors for Li-S batteries. The membrane cathode has a high electrical conductivity and renders a long life of sulphur of over 100 charge-discharge cycles. High discharge capacity of sulphur was attained at 712 mA h g(sulphur)(-1) (23 wt% S) and 520 mA h g(sulphur)(-1) (50 wt% S) at a high current density (6 A g(sulphur)(-1)). The overall capacity of the flexible cathode correspondingly reaches 163 mA h g(-1) (23 wt% S) and 260 mA h g(-1) (50 wt% S). These results demonstrate the great potential of this nanostructured flexible membrane as a cathode for Li-S batteries with fast charge-discharge performance and long life.

关键词: rechargeable lithium batteries;positive electrode materials;cell;temperature;composites;capacity;oxide

Local structures of the tetragonal Gd3+-V-M and Gd3+-Li+ centers in perovskite fluorides

Radiation Effects and Defects in Solids

The zero-field splittings b(2)(o) of the tetragonal Gd3+-V-M and Gd3+-Li+ centers for Gd3+ ions in fluoroperovskite crystals have been studied on the basis of the superposition model in which the value of t(2) (b) over bar(2) is Obtained from the stress-dependence of EPR spectra for RbCaF3:Gd3+ crystal. From the studies, the local structures of both tetragonal centers in fluoroperovskite crystals are obtained and the results are discussed.

关键词: electron paramagnetic resonance;local crystalline structure;superposition model;Gd3+;fluoroperovskite;electron-paramagnetic-res;crystals;cr-3+-li+;spectra;epr

Secondary M6C precipitation in K40S cobalt-base alloy

Materials Letters

Secondary M,C precipitation was investigated in K40S cobalt-base alloy after 100 h aging at 950 degreesC. The results showed that it was closely related to the tungsten-rich zones inherited from the as-cast condition and the degeneration of the primary M7C3 carbide. A direct element reaction, 6M + C --> M6C, in which C comes from the decomposition of the M7C3 carbides, is suggested as the mechanism of secondary M6C precipitation in K40S alloy. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词: M6C precipitation;aging;M7C3 carbide;superalloy

INFLUENCE OF GRAIN SIZE AND ORDERING OF PARENT PHASE ON M_s IN A CuZnAl ALLOY CONTAINING BORON

WU Jianxin JIANG Bohong XU Zuyao (T.Y.Hsu) Shanghai Jiaotong University , Shanghai , China Associate Professor , Dept.of Materials Science and Engineering , Shanghai Jiaotong University , Shanghai , China

金属学报(英文版)

The effect of grain size and ordering of the parent phase on the critical points of thermoelastic martensitic transformation in Cu-25.62 Zn-3.97 Al-0.0018 B(wt-%)shape memory alloy has been investigated.Based on the thermodynamics of phase transformation,a linear rela- tionship between the starting temperature of martensitic transformation and the reciprocal of the square root of grain size is obtained,i.e.M_s temperature rises with increasing grain size. It shows a good agreement with the results of electric resistance measurement.Applying the Landau's theory,a quantitative relationship between M_s and the ordering parameter of the parent phase is set up,which is well confirmed by the results of X-ray diffraction and electric resistance measurement.The activation energy of the ordering process in the parent phase of the alloy is calculated to be 46 kJ/mol.

关键词: Cu-Zu-Al , null , null , null , null

Prediction of Solid-Liquid Interface Stability by Coupling M-S Model with CALPHAD Method

Ruijie ZHANG , Zhi HE , Zhongwei CHEN , Wanqi JIE

材料科学技术(英文)

A method to predict the solid-liquid interface stability during unidirectional solidification is developed by coupling M-S model with CALPHAD method. The method was applied to Al-0.38 Zn and Al-0.34 Si-0.14 Mg (wt pct) alloys, and the predicted results were compared with some former experimental data of the two alloys. The good agreement between the calculation results and the experimental data demonstrates the superiority of the present method to the classical one based on constant parameter assumptions.

关键词: Interface stability , null , null

  • 首页
  • 上一页
  • 1
  • 2
  • 3
  • 4
  • 5
  • 下一页
  • 末页
  • 共3722页
  • 跳转 Go

出版年份

刊物分类

相关作者

相关热词