Simultaneous Cation-Substitution Effects on Superconducting Properties of Sm-Ba-Cu Oxide Superconductors

同时阳离子取代对 Sm-Ba-Cu 氧化物超导体超导性能的影响

基本信息

批准号：
08455299
负责人：
YAMAUCHI Hisao
金额：
$ 4.74万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1998
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455299/
关键词：
Sm-123 Y-123 Superconductivity Critical current density Peak effect Oxygen depleted region Twin boundary Pinning effect 酸素欠損ピン止め中心磁束ピン止め相分離

项目摘要

Cation-stoichiometric is SmBa_2Cu_3O_<7-d>(Sm-123) samples were synthesized to exclude contribution of pinning at particles of cation-nonstoichiometric phases and second phases to peak effect of J_c The samples were annealed in different conditions and had various oxygen contents. From results of Raman scattering, powder x-ray diffractometry and Rietveld analysis, cation-stoichiometric Sm-123 samples were successfully obtained. A Sm-123 sample with oxygen content, 7-d,=6.84 exhibited peak effect and its J_c value at 77 K and 1 T was 10kA/cm^2. On the other hand, samples with 7-d=6.89 and 6.95 did not exhibit the peak effect Contrary to the previous reports, it was concluded that oxygen depleted regions would work for the pinning to exhibit the peak effect in Sm-123 superconductors.A novel transmission electron microscopy technique termed as large area high-resolution transmission electron microscopy(LA_HRTEM) was developed to identyfy unknown origin of the peak effect in Y-Ba-Cu-O supe … More rconducting bulks. A specimen fabrication method was also developed for energy dispersive x-ray analyses in LA-HRTEM observations. Superconducting bulks of Y-Ba-Cu-O were synthesized by a melt growth technique under varied oxygen partial pressure. Distributions of grain sizes for Y_2BaCuO-(Y-211) particles and inter-twin-boundary-distances were measured utilizing LA-HRTEM. Area of the interface between the Y-211 particles and the Y-123 matrix was found to be proportional to the J_c value at low magntic fields. On the other hand, the inter-twin-boundary-distance was inversely proportional to the J_c value at high magnetic fields. From these results, oxygen depleted regions in the vicinity of the twin boundaies would work for pinning to exhibit the peak effect, while contribution of the interface between Y-211 particles and Y-123 matrix to the pinning for the appearance of the peak effect was very limited. A heat treatment program was developed to appear the peak effect reversively and confirmed the validity of the guiding principle for designing mateirals. Less

合成了阳离子化学计量的 SmBa_2Cu_3O_<7-d>(Sm-123) 样品，以排除阳离子非化学计量相和第二相颗粒钉扎对 J_c 峰值效应的影响。样品在不同条件下退火，并具有不同的氧含量根据拉曼散射、粉末X射线衍射和Rietveld分析的结果，成功制备了阳离子化学计量的Sm-123样品。获得了氧含量7-d=6.84的Sm-123样品，其在77K和1T下的J_c值为10kA/cm^2，而7-d=6.89的样品则表现出峰值效应。 6.95 没有表现出峰值效应与之前的报道相反，得出的结论是，氧耗尽区域将有助于钉扎，以在 Sm-123 中表现出峰值效应开发了一种称为大面积高分辨率透射电子显微镜（LA_HRTEM）的新型透射电子显微镜技术，用于识别 Y-Ba-Cu-O 超导体中峰值效应的未知来源。还开发用于 LA-HRTEM 观测中的能量色散 X 射线分析 Y-Ba-Cu-O 超导块体是通过在不同氧分压下的熔体生长技术合成的。利用 LA-HRTEM 测量了 Y_2BaCuO-(Y-211) 颗粒的晶粒尺寸分布和孪晶间的边界距离，发现了 Y-211 颗粒和 Y-123 基体之间的界面面积。在低磁场下，孪晶间边界距离与 J_c 值成正比。结果表明，孪晶边界附近的贫氧区域将有助于钉扎表现出峰值效应，而Y-211颗粒和Y-123基体之间的界面对钉扎对峰值效应出现的贡献非常有限开发了可逆地出现峰值效应的热处理程序，并证实了Less设计指导原则的有效性。

项目成果

期刊论文数量（35）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

“Large-Area TEM" Observation of the Distribution of Y-2 1 1 Particles in YBCO Superconductors Melt-Grown under Varying Oxygen Pressure

变氧压下熔融生长YBCO超导体中Y-2 1 1粒子分布的“大面积TEM”观察

DOI：
发表时间：
1998
期刊：
Advances in Superconductivity x 2
影响因子：
0
作者：
H. Suematsu;H. Okamura;S. Nagaya;H. Yamauchi
通讯作者：
H. Yamauchi

M.Kawano: "Oxygen-Content Dependence of Critical Current Density of SmBa_2Cu_3Oy Superconductrs" Appl.Superconductivity. (印刷中).

M. Kawano：“SmBa_2Cu_3Oy 超导体临界电流密度的氧含量依赖性”应用（正在出版）。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Peak Effect in Jc of the Cation-Stoichiometoric SmBa_2Cu_3O_y Superconductor

阳离子化学计量SmBa_2Cu_3O_y超导体的Jc峰值效应

DOI：
发表时间：
1997
期刊：
Appl. Superconductivity 5/(1-6)
影响因子：
0
作者：
M. Kawano;H. Suematsu;T. Onda;M. Hayakawa;H. Ogiwara;M. Karppinen;H. Yamauchi
通讯作者：
H. Yamauchi

Enhanced Pinning and Peak Effect in Overdoped (Hg, Pb)(Sr, Ba)_2Ca_2Cu_3O_<8+8> Superconductors

过掺杂 (Hg, Pb)(Sr, Ba)_2Ca_2Cu_3O_<8 8> 超导体中增强的钉扎效应和峰值效应