材料期刊网

Thermoelectric Characterization of (Na1-yMy)1.6Co2O4 (M=K, Ca, Sr)

Ying LI

材料科学技术（英文）

Oxide materials NaCo2O4 and (Na1-yMy)1.6Co2O4 (M=K, 0.05≤y≤0.35; M=Ca, Sr, 0.10≤y≤0.40) were prepared by a sol-gel method. Experimental results indicated that the Seebeck coefficient and the Power-factor of Na Co2O4 were improved by doping Ca and Sr but not by K. The Power-factor of NaCo2O4 is in its maximum, 1.68×10-4 W•m-1•K-2 and 11% bigger than that of the original one when the dopant fraction of Ca was 0.1. Doping Sr makes NaCo2O4 have the biggest Power-factor, 1.68×10-4 W•m-1•K-2 that is 50% bigger than the non-doping oxide. The experimental results indicate that suitable dopants and addition amounts could improve the thermoelectric properties of NaCo2O4 greatly.

关键词: Thermoelectric materials , materials , Electric , proper

Ti-6Al-2Zr-1M0-1V合金的热变形行为

洪权 , 张振祺

航空材料学报 doi:10.3969/j.issn.1005-5053.2001.01.003

在Gleeble-1500热模拟机上对Ti-6A1-2Zr-1Mo-1V钛合金铸态材料进行了恒温和恒应变速率下的热压缩变形实验，温度范围是700～1000℃，应变速率范围是5×10-3s～450s-1，测试了其真应力-真应变曲线，观察了变形后的组织。结果表明：合金在不同变形条件下其软化机制分别受动态回复和动态再结晶所控制，并且应变速率敏感指数随变形温度的升高而增大。 关键词：Ti-6Al-2Zr-1Mo-1V钛合金；动态再结晶；热压缩；应变速率敏感指数

关键词: Ti-6Al-2Zr-1Mo-1V钛合金 , 动态再结晶 , 热压缩 , 应变速率敏感指数

M_1-M_2-x-y系优势区相图的绘制及其应用

王龙章 , 黄克雄 , 骆如铁 , 姚渝 , 叶大陆 , 陈新民

金属学报

本文讨论了双金属共存体系M_1-M_2-x-y,当两种金属的化合物相互作用生成多金属化合物时,优势区相图的绘制原理、方法及计算机程序。通过绘制Zn-Fe-SO系的优势区相图,分析了ZnO·Fe_2O_3的生成及稳定条件,并说明了其在硫化锌矿焙烧中的指导作用。

关键词: M_1-M_2-x-y体系 , predominance diagram , roasting , zinc sulfide ore

DRAWING PREDOMINANCE DIAGRAM OF M_1—M_2—x—y SYSTEM AND ITS APPLICATION

WANG Longzhang HUANG Kexiong LUO Rutie YAO Yu YE Dalu CHEN Xinmin Central South University of Technology , Changsha , China

金属学报(英文版)

Discussions were made of the principle,method and computer program for drawing the pre- dominance diagrams of the bi-metal co-existed system M_1-M_2-x-y in which the multi-me- tallic compounds may be produced by interaction between compounds of both metals.The formation of zinc ferrite and its stable region have been analyzed through drawing Zn-Fe-S-O system predominance diagrams.The availability of the diagram is given the di- rection to roast the zinc sulfide ore as well.

关键词: system M_1-M_2-x-y , null , null , null

Synthesis and anti-corrosion research of 2,5-bis(benzylidenehydrazino)-1,3,4-thiadiazole compounds

Chinese Journal of Organic Chemistry

2,5-Dihydrazino-1,3,4-thiadiazole was prepared by 2,5-dimecapto-1,3,4-thiadiazole and hydrazine, and then the six novel different 2,5-bis(benzylidenehydrazino)-1,3,4-thiadiazole compounds were obtained by a condensation reaction of 2,5-dihydrazino-1,3,4-thiadiazole with substituted benzaldehyde and structurally confirmed by elemental analysis, IR, H-1 NMR and mass spectra. The result indicates that the six 2,5-bis(benzylidenehydrazino)-1,3,4-thiadiazole compounds are of definite inhibition against silver surface in corrosion jet fuel.

关键词: 2,5-dimercapto-1,3,4-thiadiazole;hydrazine;benzaldehyde;aldehyde-hydrazone;synthesis;anti-corrosion;derivatives

铁素体--马氏体钢K1和K2在超临界水中的腐蚀行为

魏懿 , 尹开锯 , 刘锦云 , 邱绍宇

中国腐蚀与防护学报

用扫描电镜（SEM）及能谱（EDS）和X射线衍射（XRD）技术研究国产铁素体-马氏体K1和K2钢在500℃、25 MPa超临界水环境下的腐蚀行为。结果表明，试样表面形成了稳定的氧化膜，氧化膜为双层结构，外层为多孔的磁铁矿，内层为致密的铁、铬复合氧化物。腐蚀动力学结果显示，两种材料的腐蚀行为遵循抛物线规律。K2钢在超临界水中的腐蚀增重较K1钢略高。

关键词: 铁素体-马氏体钢 , supercritical water , corrosion oxidation , oxide scale

(da)/(dN)与K_1间关系的探讨

陈篪

金属学报

本文证明我们所建议的关系: (da/dN)-C[(△K)~2-K_2~2/K_1~2-(△K)~2]~p能够很好地表达R=(K_(min)/K_(max))=常数时(da/dN)随△K的全部变化,其中P值在1左右,C约在3×10~(-3)—10~(-2)毫米/周之间。

关键词:

正极材料Li(Ni1/3Co1/3-xMn1/3)MxO2(M=Ti, Mg)的合成及性能

杨平 , 张传福 , 戴曦 , 樊友奇 , 湛菁 , 蒋伟燕

中国有色金属学报

采用草酸盐前驱体合成Ti4+、Mg2+掺杂正极材料Li(Ni1/3Co1/3-xMn1/3)MxO2(M=Ti, Mg).利用XRD和SEM对其结构和形貌进行表征,并采用循环伏安、交流阻抗、恒流/恒压充放电测试其电化学性能.结果表明:Ti4+、Mg2+掺杂后晶胞体积增大,大倍率充放电时LiNi1/3Co1/3Mn1/3O2的电化学反应阻抗Rct降低,其大倍率充放电性能得到改善,Ti4+掺杂效果更好;当掺杂量x＝0.025时,材料晶型完整,具有单一的a-NaFeO2层状结构;1C倍率时Li(Ni1/3Co1/3-0.025Mn1/3)Ti0.025O2的第二循环放电容量为143.2 mA-h/g,2C时为128.0 mA-h/g,经100次循环后容量分别为132.5和115.8 mA-h/g,容量保持率为92.53%和90.47%.

关键词: LiNi1/3Co1/3Mn1/3O2 , 锂离子电池 , 正极材料 , 电化学性能

A1对M2高速钢凝固过程的作用

李彦军 , 姜启川 , 何镇明 , 赵宇光 , 葛僚海

材料研究学报

研究了A1在M2高速钢凝固过程中的行为及其对凝固组织的影响.结果表明,A1具有扩大δ铁素体区,促进以往状树枝晶方式结晶的作用;A1在M2钢中呈负偏析分布,并参与形成M2C共晶碳化物.A1还降低共晶碳化物的分解温度,使共晶碳化物在高温加热时易于分解和粒化.

关键词: 铝 , null , null , null

MAGNETIC PROPERTIES OF Nd_2(Fe_(1-x)M_x)_(14)B(M=C,Si)ALLOYS

XING Feng JIANG Chao HE Wenwang Department of Physics , Peking University , Beijing , China [Originally published in ACTA METALL SIN (CHINESEEDN) 24 (5) 1988pp B348—B352 , received 22 October 1986:in revised form 8 May 1987]

金属学报(英文版)

The magnetic properties of Nd_2(Fe_(1-x)M_x)_(14)B(M=C and Si) compounds have been investi- gated.Substituting Fe by small amount of metalloid C and Si atoms,the compounds are in tetragonal structure and have uniaxial anisotropy.The substitution of C for part of Fe de- creases the Curie temperature of the compounds and the intrinsic coercivity of bond samples at low temperature.The replacement of Fe by Si makes the Curie temperature increase with a maximum at the vicinity of x=0.15.When the range of the content of Si is 0≤x≤0.10,the coercivity distinctly increases at room temperature.from 62.7 kA/m at x=0 to 138.7kA/m at x=0.06,where the residual magnetization has a maximum:in the mean time the saturation magnetization decreases only by a small amount.

关键词: Nd-Fe-B alloy , null , null