...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of materials science >Solubility limit of tetravalent Zr nanoparticles in Bi-2223 crystal lattice and evaluation of fundamental characteristic properties of new system
【24h】

Solubility limit of tetravalent Zr nanoparticles in Bi-2223 crystal lattice and evaluation of fundamental characteristic properties of new system

机译：四价Zr纳米粒子在Bi-2223晶格中的溶解度极限及新体系基本特征的评价。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In this comprehensive work, we focus sensitively on the changes of microstructural, electrical, superconducting and mechanical properties belonging to the bulk Bi_(1.7)Pb_(0.4)Sr_(2.0)Ca_(2.0)Zr_xCu_(3.1)O_y materials with the different Zr nanoparticles (0 ≤ x ≤ 1.0) inserted in the superconducting matrix. The characterizations of the materials prepared are experimentally performed by bulk density, dc resistivity (p-T), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), electron dispersive X-ray (EDX) and Vickers microhardness (H_v) investigations. It is found that all the characteristics given above (especially superconducting properties) degrade considerably with the increment in the Zr addition level, and in fact they reach to the global minimum points in case of the maximum dopant level. The main reason of the rapid decrement in the electrical and superconducting properties stems from the presence of the localization problem in the CU-O_2 consecutively stacked layers. Likewise, the Zr foreign addition increases the artificial random defects, dislocations and grain boundary weak-links in the superconducting system, even being favored by the SEM examinations. At the same time, the EDX surveys indicate that the Zr nanoparticles in the tetravalent state prefer to substitute for the divalent states of the Cu inclusions through the crystal structure as a result of their close ionic radius values (86 pm for Zr~(4+) ion and 87 pm for Cu~(2+) ion). Thus, the differentiation of the electronegativity reduces the mobile hole concentration in the Cu-O_2 slabs. Additionally, the XRD experimental findings show that there is a systematic decrement in the Bi-2223 (high) phase up to the Zr concentration level of x = 0.70 beyond which new characteristics peaks of ZrO_2 appear immediately. This is in relation to the fact that the solubility limit corresponding to the Zr foreign impurity in the Bi-2223 system is about x = 0.70. Similarly, the regular decrement in both the c-axis length and crystallite size with the dopant confirms the deterioration of the superconducting properties. Furthermore, the dramatic reduction of the H_v values stems from the suppression of the crystallinity and connection quality in the intergrain coupling of the superconducting samples exhibiting typical Indentation Size Effect behavior due to the existence of both elastic and plastic deformations in the system.
机译：在这项全面的工作中，我们敏感地关注了具有不同Zr的Bi_（1.7）Pb_（0.4）Sr_（2.0）Ca_（2.0）Zr_xCu_（3.1）O_y材料的微观结构，电，超导和机械性能的变化纳米粒子（0≤x≤1.0）插入超导基质中。通过堆积密度，直流电阻率（pT），X射线粉末衍射（XRD），扫描电子显微镜（SEM），电子弥散X射线（EDX）和维氏显微硬度（H_v）研究来对制备的材料进行表征。已经发现，以上给出的所有特性（特别是超导特性）都随着Zr添加量的增加而大大降低，实际上，在最大掺杂量的情况下，它们达到了全局最小值。电和超导性能快速下降的主要原因是由于CU-O_2连续堆叠的层中存在局部化问题。同样，Zr外来添加会增加超导系统中的人为随机缺陷，位错和晶界薄弱环节，甚至受到SEM检查的欢迎。同时，EDX调查表明，由于四价态的Zr纳米粒子具有接近的离子半径值（Zr〜（4+为86 pm），因此更倾向于通过晶体结构替代Cu夹杂物的二价态。 ）和Cu〜（2+）离子为87 pm）。因此，电负性的差异降低了Cu-O_2平板中的活动空穴浓度。此外，XRD实验结果表明，Bi-2223（高）相在Zr浓度水平x = 0.70时有系统的减小，超过此值ZrO_2就会立即出现新的特征峰。这与以下事实有关：与Bi-2223体系中的Zr外来杂质相对应的溶解度极限约为x = 0.70。类似地，随着掺杂剂c轴长度和微晶尺寸的规则减小证实了超导性能的劣化。此外，H_v值的显着降低是由于在系统中同时存在弹性变形和塑性变形的情况下，由于表现出典型的压痕尺寸效应行为的超导样品的晶粒间耦合而抑制了结晶度和连接质量。

著录项

  • 来源
    《Journal of materials science》 |2016年第2期|1854-1865|共12页
  • 作者

    N. K. Saritekin; C. Terzioglu; M. Pakdil; T. Turgay; G. Yildirim;

  • 作者单位

    Department of Physics, Abant Izzet Baysal University, 14280 Bolu, Turkey;

    Department of Physics, Abant Izzet Baysal University, 14280 Bolu, Turkey;

    Department of Mechanical Engineering, Abant Izzet Baysal University, 14280 Bolu, Turkey;

    Faculty of Fine Arts Architecture, Sakarya University, 54187 Sakarya, Turkey;

    Department of Mechanical Engineering, Abant Izzet Baysal University, 14280 Bolu, Turkey;

  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号