Author K. Tokimasa1) and M. Miyahara2) 1) Department of Mechanical Engineering
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School of BiologyOriented Science and Technology
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Kinki University
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Uchitacho
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Wakayama
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Japan2) Corporate Research & Development Laboratories
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Sumitomo Metal Industries
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Ltd.
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Amagasaki
,
JapanManuscript received 18 October 1998
金属学报(英文版)
The two procedures based on the strain range partitioning approach are proposed for evaluating the remaining life by measuring the surface crack length. Both the procedures require that the material parameters describing the creepfatigue damage rule built and modified by the authors and the strain waveform applied have been clarified before the evaluation. One of the procedures can be used only when the total number of the operation cycles n are known, whereas the other is useful even when n is unknown, though it needs the additional crack length measurement. In the latter the surface crack length must be measured not only at n but also at n+n, where n is a given interval of cycles. The results of their application to Mod.9Cr1Mo and 316LC steel smooth specimens subjected to the IJ type creepfatigue loading are shown.
关键词:
creepfatigue
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null
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null
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null
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null
Ying LI
材料科学技术（英）
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
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materials
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Electric
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proper
材料科学技术（英）
The cyclic plastic straining electrode technique has been used to investigate the transient electrochemical behaviour of Fe-26Cr-1Mo stainless steel in 1M H2SO4 solution at a passive potential. The influence of plastic strain amplitude and plastic strain rate on the dissolution current response was analysed. The experimental results showed that the transient current was dependent on the competitive process of the surface film rupture and repassivation of the new surface. The high plastic strain amplitude and the high plastic strain rate caused a change of electrochemical activity of specimen surface. In the condition of low strain amplitude and strain rate:, the characteristics of current response was mainly relative to the process of new surface repassivation. The competition kinetics has been analysed through the comparison of plastic strain rate and repassivating rate.
关键词:
王龙章
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黄克雄
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骆如铁
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姚渝
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叶大陆
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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
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predominance diagram
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roasting
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zinc sulfide ore
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:
杨平
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张传福
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戴曦
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樊友奇
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湛菁
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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
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锂离子电池
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正极材料
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电化学性能
