Fabrication of oxide superconducting wire by elongation suppressed rolling.

通过抑制伸长轧制制造氧化物超导线材。

• 批准号: 03452248
• 负责人: SAITO Yoshihiro
• 金额: $ 3.84万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03452248/
• 关键词: high Tc superconductor; oxide superconductor; superconducting wire; satellite mill; asymmetric rolling; critical current density; cross rolling; elongation suppressed rolling; 異径ロ-ル圧延

Yttrium-based oxide super conductor sheathed in aluminum tube was rolled into tapes in order to simulate the deformation of oxide sheathed in silver tube. The effect of pass schedule on deformation of oxide core was studied. The lateral spread increases with increasing reduction per pass and with decreasing the diameter of tube before rolling. The well known results obtained in usual bulk rolling that the lateral spread increases with increasing roll gap ratio holds true in rolling of oxide sheathed in metal tube. Non uniform core distribution through longitudinal direction becomes notable when rolled in pass schedule with high reduction per pass. The effect of rolling condition on critical current of silver sheathed Bi-based oxide wire was studied. The tape of 2mm in thickness was rolled to 1mm in thickness (intermediate rolling) by satellite mill (elongation suppressed rolling, 3passes), asymmetric rolling (11passes) or conventional flat rolling (3passes), then rolled to tape of 0.2mm in thickness by flat rolling. The tape rolled by satellite mill exhibited highest Jc, though the superconductor/silver interface was irregular. Application of satellite mill rolling (8passes, 30stages, 2.5%/stage) or conventional rolling (30passes, 2.5%/pass) eliminates this irregularity. The mechanical deformation between two sintering processes (intermediate deformation) exerts a marked effect on Jc. The tape for which cross rolling is adopted as intermediate deformation exhibits higher Jc than that for which conventional rolling is adopted as intermediate rolling. The c axes of the grains of cross rolled tape are oriented nearly perpendicular to the plane of the tape with slight rotating components about longitudinal direction. Those of conventionally rolled tape are also oriented nearly perpendicular to the plane of the tape, but have slight rotating components about transverse direction. This difference in texture seems to induce the difference in Jc.

将基于铝管中的YTTrium氧化物超级导体卷成磁带，以模拟银管中护套的氧化物的变形。研究了通行时间表对氧化物核心变形的影响。横向扩散会随着每次平均减少的增加而增加，并在滚动前减小管的直径。在通常的散装滚动中获得的众所周知的结果是，随着滚动间隙比的增加，横向扩散在金属管中的氧化物滚动中确实存在。通过纵向方向进行非均匀的核心分布在通过时间表中滚动，每次通过时较高。研究了滚动条件对银色鞘基于BI基氧化线的临界电流的影响。用卫星磨坊（抑制滚动滚动，3次），不对称滚动（11次通道）或常规的平面滚动（3个通道），将厚度为2mm的胶带滚动至1mm的厚度（中间滚动）（中间滚动），然后将0.2mm的胶带滚动到厚度为0.2mm平坦的滚动。卫星厂滚动的胶带表现出最高的JC，尽管超导体/银界面不规则。卫星磨坊滚动的应用（8个通道，30阶段，2.5％/阶段）或常规滚动（30个通道，2.5％/通过）消除了这种不规则性。两个烧结过程（中间变形）之间的机械变形对JC产生了明显的影响。采用交叉滚动作为中间变形的胶带表现出的JC高于将常规滚动作为中间滚动采用的胶带。交叉卷胶带的颗粒的C轴几乎垂直于胶带的平面，围绕纵向方向略有旋转组件。传统卷曲的胶带的定向几乎垂直于胶带的平面，但在横向方向上有轻微的旋转组件。这种纹理的差异似乎会导致JC的差异。